Actual source code: mpiaij.c

  1: #include <../src/mat/impls/aij/mpi/mpiaij.h>
  2: #include <petsc/private/vecimpl.h>
  3: #include <petsc/private/sfimpl.h>
  4: #include <petsc/private/isimpl.h>
  5: #include <petscblaslapack.h>
  6: #include <petscsf.h>
  7: #include <petsc/private/hashmapi.h>

  9: /* defines MatSetValues_MPI_Hash(), MatAssemblyBegin_MPI_Hash(), and MatAssemblyEnd_MPI_Hash() */
 10: #define TYPE AIJ
 11: #define TYPE_AIJ
 12: #include "../src/mat/impls/aij/mpi/mpihashmat.h"
 13: #undef TYPE
 14: #undef TYPE_AIJ

 16: static PetscErrorCode MatReset_MPIAIJ(Mat mat)
 17: {
 18:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

 20:   PetscFunctionBegin;
 21:   PetscCall(PetscLogObjectState((PetscObject)mat, "Rows=%" PetscInt_FMT ", Cols=%" PetscInt_FMT, mat->rmap->N, mat->cmap->N));
 22:   PetscCall(MatStashDestroy_Private(&mat->stash));
 23:   PetscCall(VecDestroy(&aij->diag));
 24:   PetscCall(MatDestroy(&aij->A));
 25:   PetscCall(MatDestroy(&aij->B));
 26: #if PetscDefined(USE_CTABLE)
 27:   PetscCall(PetscHMapIDestroy(&aij->colmap));
 28: #else
 29:   PetscCall(PetscFree(aij->colmap));
 30: #endif
 31:   PetscCall(PetscFree(aij->garray));
 32:   PetscCall(VecDestroy(&aij->lvec));
 33:   PetscCall(VecScatterDestroy(&aij->Mvctx));
 34:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));
 35:   PetscCall(PetscFree(aij->ld));
 36:   PetscFunctionReturn(PETSC_SUCCESS);
 37: }

 39: static PetscErrorCode MatResetHash_MPIAIJ(Mat mat)
 40: {
 41:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
 42:   /* Save the nonzero states of the component matrices because those are what are used to determine
 43:     the nonzero state of mat */
 44:   PetscObjectState Astate = aij->A->nonzerostate, Bstate = aij->B->nonzerostate;

 46:   PetscFunctionBegin;
 47:   PetscCall(MatReset_MPIAIJ(mat));
 48:   PetscCall(MatSetUp_MPI_Hash(mat));
 49:   aij->A->nonzerostate = ++Astate, aij->B->nonzerostate = ++Bstate;
 50:   PetscFunctionReturn(PETSC_SUCCESS);
 51: }

 53: PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
 54: {
 55:   PetscFunctionBegin;
 56:   PetscCall(MatReset_MPIAIJ(mat));

 58:   PetscCall(PetscFree(mat->data));

 60:   /* may be created by MatCreateMPIAIJSumSeqAIJSymbolic */
 61:   PetscCall(PetscObjectCompose((PetscObject)mat, "MatMergeSeqsToMPI", NULL));

 63:   PetscCall(PetscObjectChangeTypeName((PetscObject)mat, NULL));
 64:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatStoreValues_C", NULL));
 65:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatRetrieveValues_C", NULL));
 66:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatGetMultPetscSF_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatIsTranspose_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetHash_C", NULL));
 71:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 73:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 74:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 75: #if PetscDefined(HAVE_CUDA)
 76:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 77: #endif
 78: #if PetscDefined(HAVE_HIP)
 79:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 80: #endif
 81: #if PetscDefined(HAVE_KOKKOS_KERNELS)
 82:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 83: #endif
 84:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 85: #if PetscDefined(HAVE_ELEMENTAL)
 86:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 87: #endif
 88: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
 89:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 90: #endif
 91: #if PetscDefined(HAVE_HYPRE)
 92:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 93:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 94: #endif
 95:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 96:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 97:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 98:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 99:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
100:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
101: #if PetscDefined(HAVE_MKL_SPARSE)
102:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
103: #endif
104:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
105:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
106:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
107:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
108:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
109:   PetscFunctionReturn(PETSC_SUCCESS);
110: }

112: static PetscErrorCode MatGetRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
113: {
114:   Mat B;

116:   PetscFunctionBegin;
117:   PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, &B));
118:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject)B));
119:   PetscCall(MatGetRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
120:   PetscCall(MatDestroy(&B));
121:   PetscFunctionReturn(PETSC_SUCCESS);
122: }

124: static PetscErrorCode MatRestoreRowIJ_MPIAIJ(Mat A, PetscInt oshift, PetscBool symmetric, PetscBool inodecompressed, PetscInt *m, const PetscInt *ia[], const PetscInt *ja[], PetscBool *done)
125: {
126:   Mat B;

128:   PetscFunctionBegin;
129:   PetscCall(PetscObjectQuery((PetscObject)A, "MatGetRowIJ_MPIAIJ", (PetscObject *)&B));
130:   PetscCall(MatRestoreRowIJ(B, oshift, symmetric, inodecompressed, m, ia, ja, done));
131:   PetscCall(PetscObjectCompose((PetscObject)A, "MatGetRowIJ_MPIAIJ", NULL));
132:   PetscFunctionReturn(PETSC_SUCCESS);
133: }

135: /*MC
136:    MATAIJCRL - MATAIJCRL = "aijcrl" - A matrix type to be used for sparse matrices.

138:    This matrix type is identical to `MATSEQAIJCRL` when constructed with a single process communicator,
139:    and `MATMPIAIJCRL` otherwise.  As a result, for single process communicators,
140:    `MatSeqAIJSetPreallocation()` is supported, and similarly `MatMPIAIJSetPreallocation()` is supported
141:   for communicators controlling multiple processes.  It is recommended that you call both of
142:   the above preallocation routines for simplicity.

144:    Options Database Key:
145: . -mat_type aijcrl - sets the matrix type to `MATMPIAIJCRL` during a call to `MatSetFromOptions()`

147:   Level: beginner

149: .seealso: [](ch_matrices), `Mat`, `MatCreateMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`, `MATSEQAIJ`, `MATMPIAIJ`, `MATAIJ`
150: M*/

152: static PetscErrorCode MatBindToCPU_MPIAIJ(Mat A, PetscBool flg)
153: {
154:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

156:   PetscFunctionBegin;
157: #if PetscDefined(HAVE_CUDA) || PetscDefined(HAVE_HIP) || PetscDefined(HAVE_VIENNACL)
158:   A->boundtocpu = flg;
159: #endif
160:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
161:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

163:   /* In addition to binding the diagonal and off-diagonal matrices, bind the local vectors used for matrix-vector products.
164:    * This maybe seems a little odd for a MatBindToCPU() call to do, but it makes no sense for the binding of these vectors
165:    * to differ from the parent matrix. */
166:   if (a->lvec) PetscCall(VecBindToCPU(a->lvec, flg));
167:   if (a->diag) PetscCall(VecBindToCPU(a->diag, flg));
168:   PetscFunctionReturn(PETSC_SUCCESS);
169: }

171: static PetscErrorCode MatSetBlockSizes_MPIAIJ(Mat M, PetscInt rbs, PetscInt cbs)
172: {
173:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)M->data;

175:   PetscFunctionBegin;
176:   if (mat->A) {
177:     PetscCall(MatSetBlockSizes(mat->A, rbs, cbs));
178:     PetscCall(MatSetBlockSizes(mat->B, rbs, 1));
179:   }
180:   PetscFunctionReturn(PETSC_SUCCESS);
181: }

183: static PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M, IS *keptrows)
184: {
185:   Mat_MPIAIJ      *mat = (Mat_MPIAIJ *)M->data;
186:   Mat_SeqAIJ      *a   = (Mat_SeqAIJ *)mat->A->data;
187:   Mat_SeqAIJ      *b   = (Mat_SeqAIJ *)mat->B->data;
188:   const PetscInt  *ia, *ib;
189:   const MatScalar *aa, *bb, *aav, *bav;
190:   PetscInt         na, nb, i, j, *rows, cnt = 0, n0rows;
191:   PetscInt         m = M->rmap->n, rstart = M->rmap->rstart;

193:   PetscFunctionBegin;
194:   *keptrows = NULL;

196:   ia = a->i;
197:   ib = b->i;
198:   PetscCall(MatSeqAIJGetArrayRead(mat->A, &aav));
199:   PetscCall(MatSeqAIJGetArrayRead(mat->B, &bav));
200:   for (i = 0; i < m; i++) {
201:     na = ia[i + 1] - ia[i];
202:     nb = ib[i + 1] - ib[i];
203:     if (!na && !nb) {
204:       cnt++;
205:       goto ok1;
206:     }
207:     aa = aav + ia[i];
208:     for (j = 0; j < na; j++) {
209:       if (aa[j] != 0.0) goto ok1;
210:     }
211:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
212:     for (j = 0; j < nb; j++) {
213:       if (bb[j] != 0.0) goto ok1;
214:     }
215:     cnt++;
216:   ok1:;
217:   }
218:   PetscCallMPI(MPIU_Allreduce(&cnt, &n0rows, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)M)));
219:   if (!n0rows) {
220:     PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
221:     PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
222:     PetscFunctionReturn(PETSC_SUCCESS);
223:   }
224:   PetscCall(PetscMalloc1(M->rmap->n - cnt, &rows));
225:   cnt = 0;
226:   for (i = 0; i < m; i++) {
227:     na = ia[i + 1] - ia[i];
228:     nb = ib[i + 1] - ib[i];
229:     if (!na && !nb) continue;
230:     aa = aav + ia[i];
231:     for (j = 0; j < na; j++) {
232:       if (aa[j] != 0.0) {
233:         rows[cnt++] = rstart + i;
234:         goto ok2;
235:       }
236:     }
237:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
238:     for (j = 0; j < nb; j++) {
239:       if (bb[j] != 0.0) {
240:         rows[cnt++] = rstart + i;
241:         goto ok2;
242:       }
243:     }
244:   ok2:;
245:   }
246:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), cnt, rows, PETSC_OWN_POINTER, keptrows));
247:   PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
248:   PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
249:   PetscFunctionReturn(PETSC_SUCCESS);
250: }

252: static PetscErrorCode MatDiagonalSet_MPIAIJ(Mat Y, Vec D, InsertMode is)
253: {
254:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)Y->data;
255:   PetscBool   cong;

257:   PetscFunctionBegin;
258:   PetscCall(MatHasCongruentLayouts(Y, &cong));
259:   if (Y->assembled && cong) PetscCall(MatDiagonalSet(aij->A, D, is));
260:   else PetscCall(MatDiagonalSet_Default(Y, D, is));
261:   PetscFunctionReturn(PETSC_SUCCESS);
262: }

264: static PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M, IS *zrows)
265: {
266:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)M->data;
267:   PetscInt    i, rstart, nrows, *rows;

269:   PetscFunctionBegin;
270:   *zrows = NULL;
271:   PetscCall(MatFindZeroDiagonals_SeqAIJ_Private(aij->A, &nrows, &rows));
272:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));
273:   for (i = 0; i < nrows; i++) rows[i] += rstart;
274:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), nrows, rows, PETSC_OWN_POINTER, zrows));
275:   PetscFunctionReturn(PETSC_SUCCESS);
276: }

278: static PetscErrorCode MatGetColumnReductions_MPIAIJ(Mat A, PetscInt type, PetscReal *reductions)
279: {
280:   Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)A->data;
281:   PetscInt           i, m, n, *garray = aij->garray;
282:   Mat_SeqAIJ        *a_aij = (Mat_SeqAIJ *)aij->A->data;
283:   Mat_SeqAIJ        *b_aij = (Mat_SeqAIJ *)aij->B->data;
284:   const PetscScalar *dummy;

286:   PetscFunctionBegin;
287:   PetscCall(MatGetSize(A, &m, &n));
288:   PetscCall(PetscArrayzero(reductions, n));
289:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &dummy));
290:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &dummy));
291:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &dummy));
292:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &dummy));
293:   if (type == NORM_2) {
294:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i] * a_aij->a[i]);
295:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i] * b_aij->a[i]);
296:   } else if (type == NORM_1) {
297:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
298:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
299:   } else if (type == NORM_INFINITY) {
300:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), reductions[A->cmap->rstart + a_aij->j[i]]);
301:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]), reductions[garray[b_aij->j[i]]]);
302:   } else if (type == REDUCTION_SUM_REALPART || type == REDUCTION_MEAN_REALPART) {
303:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscRealPart(a_aij->a[i]);
304:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscRealPart(b_aij->a[i]);
305:   } else {
306:     PetscCheck(type == REDUCTION_SUM_IMAGINARYPART || type == REDUCTION_MEAN_IMAGINARYPART, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Unknown reduction type");
307:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) reductions[A->cmap->rstart + a_aij->j[i]] += PetscImaginaryPart(a_aij->a[i]);
308:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) reductions[garray[b_aij->j[i]]] += PetscImaginaryPart(b_aij->a[i]);
309:   }
310:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, reductions, n, MPIU_REAL, type == NORM_INFINITY ? MPIU_MAX : MPIU_SUM, PetscObjectComm((PetscObject)A)));
311:   if (type == NORM_2) {
312:     for (i = 0; i < n; i++) reductions[i] = PetscSqrtReal(reductions[i]);
313:   } else if (type == REDUCTION_MEAN_REALPART || type == REDUCTION_MEAN_IMAGINARYPART) {
314:     for (i = 0; i < n; i++) reductions[i] /= m;
315:   }
316:   PetscFunctionReturn(PETSC_SUCCESS);
317: }

319: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
320: {
321:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
322:   IS              sis, gis;
323:   const PetscInt *isis, *igis;
324:   PetscInt        n, *iis, nsis, ngis, rstart, i;

326:   PetscFunctionBegin;
327:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
328:   PetscCall(MatFindNonzeroRows(a->B, &gis));
329:   PetscCall(ISGetSize(gis, &ngis));
330:   PetscCall(ISGetSize(sis, &nsis));
331:   PetscCall(ISGetIndices(sis, &isis));
332:   PetscCall(ISGetIndices(gis, &igis));

334:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
335:   PetscCall(PetscArraycpy(iis, igis, ngis));
336:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
337:   n = ngis + nsis;
338:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
339:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
340:   for (i = 0; i < n; i++) iis[i] += rstart;
341:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

343:   PetscCall(ISRestoreIndices(sis, &isis));
344:   PetscCall(ISRestoreIndices(gis, &igis));
345:   PetscCall(ISDestroy(&sis));
346:   PetscCall(ISDestroy(&gis));
347:   PetscFunctionReturn(PETSC_SUCCESS);
348: }

350: /*
351:   Local utility routine that creates a mapping from the global column
352: number to the local number in the off-diagonal part of the local
353: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
354: a slightly higher hash table cost; without it it is not scalable (each processor
355: has an order N integer array but is fast to access.
356: */
357: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
358: {
359:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
360:   PetscInt    n   = aij->B->cmap->n, i;

362:   PetscFunctionBegin;
363:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
364: #if PetscDefined(USE_CTABLE)
365:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
366:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
367: #else
368:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
369:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
370: #endif
371:   PetscFunctionReturn(PETSC_SUCCESS);
372: }

374: #define MatSetValues_SeqAIJ_A_Private(row, col, value, addv, orow, ocol) \
375:   do { \
376:     if ((col) <= lastcol1) low1 = 0; \
377:     else high1 = nrow1; \
378:     lastcol1 = col; \
379:     while (high1 - low1 > 5) { \
380:       t = (low1 + high1) / 2; \
381:       if (rp1[t] > (col)) high1 = t; \
382:       else low1 = t; \
383:     } \
384:     for (_i = low1; _i < high1; _i++) { \
385:       if (rp1[_i] > (col)) break; \
386:       if (rp1[_i] == (col)) { \
387:         if (A->structure_only) goto a_noinsert; \
388:         if ((addv) == ADD_VALUES) { \
389:           ap1[_i] += value; \
390:           /* Not sure LogFlops will slow down the code or not */ \
391:           (void)PetscLogFlops(1.0); \
392:         } else ap1[_i] = value; \
393:         goto a_noinsert; \
394:       } \
395:     } \
396:     if (!A->structure_only && (value) == 0.0 && ignorezeroentries && (orow) != (ocol)) { \
397:       low1  = 0; \
398:       high1 = nrow1; \
399:       goto a_noinsert; \
400:     } \
401:     if (nonew == 1) { \
402:       low1  = 0; \
403:       high1 = nrow1; \
404:       goto a_noinsert; \
405:     } \
406:     PetscCheck(nonew != -1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", orow, ocol); \
407:     if (A->structure_only) MatSeqXAIJReallocateAIJ_structure_only(A, am, 1, nrow1, row, col, rmax1, ai, aj, rp1, aimax, nonew, MatScalar); \
408:     else MatSeqXAIJReallocateAIJ(A, am, 1, nrow1, row, col, rmax1, aa, ai, aj, rp1, ap1, aimax, nonew, MatScalar); \
409:     N = nrow1++ - 1; \
410:     a->nz++; \
411:     high1++; \
412:     /* shift up all the later entries in this row */ \
413:     PetscCall(PetscArraymove(rp1 + _i + 1, rp1 + _i, N - _i + 1)); \
414:     rp1[_i] = col; \
415:     if (!A->structure_only) { \
416:       PetscCall(PetscArraymove(ap1 + _i + 1, ap1 + _i, N - _i + 1)); \
417:       ap1[_i] = value; \
418:     } \
419:   a_noinsert:; \
420:     ailen[row] = nrow1; \
421:   } while (0)

423: #define MatSetValues_SeqAIJ_B_Private(row, col, value, addv, orow, ocol) \
424:   do { \
425:     if ((col) <= lastcol2) low2 = 0; \
426:     else high2 = nrow2; \
427:     lastcol2 = col; \
428:     while (high2 - low2 > 5) { \
429:       t = (low2 + high2) / 2; \
430:       if (rp2[t] > (col)) high2 = t; \
431:       else low2 = t; \
432:     } \
433:     for (_i = low2; _i < high2; _i++) { \
434:       if (rp2[_i] > (col)) break; \
435:       if (rp2[_i] == (col)) { \
436:         if (B->structure_only) goto b_noinsert; \
437:         if ((addv) == ADD_VALUES) { \
438:           ap2[_i] += value; \
439:           (void)PetscLogFlops(1.0); \
440:         } else ap2[_i] = value; \
441:         goto b_noinsert; \
442:       } \
443:     } \
444:     if (!B->structure_only && (value) == 0.0 && ignorezeroentries) { \
445:       low2  = 0; \
446:       high2 = nrow2; \
447:       goto b_noinsert; \
448:     } \
449:     if (nonew == 1) { \
450:       low2  = 0; \
451:       high2 = nrow2; \
452:       goto b_noinsert; \
453:     } \
454:     PetscCheck(nonew != -1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", orow, ocol); \
455:     if (B->structure_only) MatSeqXAIJReallocateAIJ_structure_only(B, bm, 1, nrow2, row, col, rmax2, bi, bj, rp2, bimax, nonew, MatScalar); \
456:     else MatSeqXAIJReallocateAIJ(B, bm, 1, nrow2, row, col, rmax2, ba, bi, bj, rp2, ap2, bimax, nonew, MatScalar); \
457:     N = nrow2++ - 1; \
458:     b->nz++; \
459:     high2++; \
460:     /* shift up all the later entries in this row */ \
461:     PetscCall(PetscArraymove(rp2 + _i + 1, rp2 + _i, N - _i + 1)); \
462:     rp2[_i] = col; \
463:     if (!B->structure_only) { \
464:       PetscCall(PetscArraymove(ap2 + _i + 1, ap2 + _i, N - _i + 1)); \
465:       ap2[_i] = value; \
466:     } \
467:   b_noinsert:; \
468:     bilen[row] = nrow2; \
469:   } while (0)

471: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
472: {
473:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
474:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
475:   PetscInt     l, *garray                         = mat->garray, diag;
476:   PetscScalar *aa, *ba;

478:   PetscFunctionBegin;
479:   /* code only works for square matrices A */

481:   /* find size of row to the left of the diagonal part */
482:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
483:   row = row - diag;
484:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
485:     if (garray[b->j[b->i[row] + l]] > diag) break;
486:   }
487:   if (l) {
488:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
489:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
490:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
491:   }

493:   /* diagonal part */
494:   if (a->i[row + 1] - a->i[row]) {
495:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
496:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, a->i[row + 1] - a->i[row]));
497:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
498:   }

500:   /* right of diagonal part */
501:   if (b->i[row + 1] - b->i[row] - l) {
502:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
503:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
504:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
505:   }
506:   PetscFunctionReturn(PETSC_SUCCESS);
507: }

509: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
510: {
511:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
512:   PetscScalar value = 0.0;
513:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
514:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
515:   PetscBool   roworiented = aij->roworiented;

517:   /* Some Variables required in the macro */
518:   Mat             A     = aij->A;
519:   Mat_SeqAIJ     *a     = (Mat_SeqAIJ *)A->data;
520:   PetscInt       *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
521:   const PetscBool ignorezeroentries = (PetscBool)(!mat->structure_only && a->ignorezeroentries);
522:   Mat             B                 = aij->B;
523:   Mat_SeqAIJ     *b                 = (Mat_SeqAIJ *)B->data;
524:   PetscInt       *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
525:   MatScalar      *aa, *ba;
526:   PetscInt       *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
527:   PetscInt        nonew;
528:   MatScalar      *ap1, *ap2;

530:   PetscFunctionBegin;
531:   PetscCall(MatSeqAIJGetArray(A, &aa));
532:   PetscCall(MatSeqAIJGetArray(B, &ba));
533:   for (i = 0; i < m; i++) {
534:     if (im[i] < 0) continue;
535:     PetscCheck(im[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, im[i], mat->rmap->N - 1);
536:     if (im[i] >= rstart && im[i] < rend) {
537:       row      = im[i] - rstart;
538:       lastcol1 = -1;
539:       rp1      = PetscSafePointerPlusOffset(aj, ai[row]);
540:       ap1      = PetscSafePointerPlusOffset(aa, ai[row]);
541:       rmax1    = aimax[row];
542:       nrow1    = ailen[row];
543:       low1     = 0;
544:       high1    = nrow1;
545:       lastcol2 = -1;
546:       rp2      = PetscSafePointerPlusOffset(bj, bi[row]);
547:       ap2      = PetscSafePointerPlusOffset(ba, bi[row]);
548:       rmax2    = bimax[row];
549:       nrow2    = bilen[row];
550:       low2     = 0;
551:       high2    = nrow2;

553:       for (j = 0; j < n; j++) {
554:         if (v && !mat->structure_only) value = roworiented ? v[i * n + j] : v[i + j * m];
555:         if (!mat->structure_only && ignorezeroentries && value == 0.0 && addv == ADD_VALUES && im[i] != in[j]) continue;
556:         if (in[j] >= cstart && in[j] < cend) {
557:           col   = in[j] - cstart;
558:           nonew = a->nonew;
559:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
560:         } else if (in[j] < 0) {
561:           continue;
562:         } else {
563:           PetscCheck(in[j] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
564:           if (mat->was_assembled) {
565:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
566: #if PetscDefined(USE_CTABLE)
567:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
568:             col--;
569: #else
570:             col = aij->colmap[in[j]] - 1;
571: #endif
572:             if (col < 0 && !((Mat_SeqAIJ *)aij->B->data)->nonew) { /* col < 0 means in[j] is a new col for B */
573:               PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));  /* Change aij->B from reduced/local format to expanded/global format */
574:               col = in[j];
575:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
576:               B     = aij->B;
577:               b     = (Mat_SeqAIJ *)B->data;
578:               bimax = b->imax;
579:               bi    = b->i;
580:               bilen = b->ilen;
581:               bj    = b->j;
582:               ba    = b->a;
583:               rp2   = PetscSafePointerPlusOffset(bj, bi[row]);
584:               ap2   = PetscSafePointerPlusOffset(ba, bi[row]);
585:               rmax2 = bimax[row];
586:               nrow2 = bilen[row];
587:               low2  = 0;
588:               high2 = nrow2;
589:               bm    = aij->B->rmap->n;
590:               ba    = b->a;
591:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
592:               PetscCheck(1 == ((Mat_SeqAIJ *)aij->B->data)->nonew, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Inserting a new nonzero at global row/column (%" PetscInt_FMT ", %" PetscInt_FMT ") into matrix", im[i], in[j]);
593:               PetscCall(PetscInfo(mat, "Skipping of insertion of new nonzero location in off-diagonal portion of matrix %g(%" PetscInt_FMT ",%" PetscInt_FMT ")\n", (double)PetscRealPart(value), im[i], in[j]));
594:             }
595:           } else col = in[j];
596:           nonew = b->nonew;
597:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
598:         }
599:       }
600:     } else {
601:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Setting off process row %" PetscInt_FMT " even though MatSetOption(,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE) was set", im[i]);
602:       if (!aij->donotstash) {
603:         mat->assembled = PETSC_FALSE;
604:         if (roworiented) {
605:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i * n), (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
606:         } else {
607:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i), m, (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
608:         }
609:       }
610:     }
611:   }
612:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
613:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
614:   PetscFunctionReturn(PETSC_SUCCESS);
615: }

617: /*
618:     This function sets the j and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
619:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
620:     No off-processor parts off the matrix are allowed here and mat->was_assembled has to be PETSC_FALSE.
621: */
622: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat_Symbolic(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[])
623: {
624:   Mat_MPIAIJ *aij    = (Mat_MPIAIJ *)mat->data;
625:   Mat         A      = aij->A; /* diagonal part of the matrix */
626:   Mat         B      = aij->B; /* off-diagonal part of the matrix */
627:   Mat_SeqAIJ *a      = (Mat_SeqAIJ *)A->data;
628:   Mat_SeqAIJ *b      = (Mat_SeqAIJ *)B->data;
629:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, col;
630:   PetscInt   *ailen = a->ilen, *aj = a->j;
631:   PetscInt   *bilen = b->ilen, *bj = b->j;
632:   PetscInt    am          = aij->A->rmap->n, j;
633:   PetscInt    diag_so_far = 0, dnz;
634:   PetscInt    offd_so_far = 0, onz;

636:   PetscFunctionBegin;
637:   /* Iterate over all rows of the matrix */
638:   for (j = 0; j < am; j++) {
639:     dnz = onz = 0;
640:     /*  Iterate over all non-zero columns of the current row */
641:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
642:       /* If column is in the diagonal */
643:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
644:         aj[diag_so_far++] = mat_j[col] - cstart;
645:         dnz++;
646:       } else { /* off-diagonal entries */
647:         bj[offd_so_far++] = mat_j[col];
648:         onz++;
649:       }
650:     }
651:     ailen[j] = dnz;
652:     bilen[j] = onz;
653:   }
654:   PetscFunctionReturn(PETSC_SUCCESS);
655: }

657: /*
658:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
659:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
660:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
661:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
662:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
663: */
664: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
665: {
666:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
667:   Mat          A    = aij->A; /* diagonal part of the matrix */
668:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
669:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)aij->A->data, *aijo = (Mat_SeqAIJ *)aij->B->data;
670:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
671:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
672:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
673:   PetscInt    *ailen = a->ilen, *aj = a->j;
674:   PetscInt    *bilen = b->ilen, *bj = b->j;
675:   PetscInt     am          = aij->A->rmap->n, j;
676:   PetscInt    *full_diag_i = aijd->i, *full_offd_i = aijo->i; /* These variables can also include non-local elements, which are set at a later point. */
677:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
678:   PetscScalar *aa = a->a, *ba = b->a;

680:   PetscFunctionBegin;
681:   /* Iterate over all rows of the matrix */
682:   for (j = 0; j < am; j++) {
683:     dnz_row = onz_row = 0;
684:     rowstart_offd     = full_offd_i[j];
685:     rowstart_diag     = full_diag_i[j];
686:     /*  Iterate over all non-zero columns of the current row */
687:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
688:       /* If column is in the diagonal */
689:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
690:         aj[rowstart_diag + dnz_row] = mat_j[col] - cstart;
691:         aa[rowstart_diag + dnz_row] = mat_a[col];
692:         dnz_row++;
693:       } else { /* off-diagonal entries */
694:         bj[rowstart_offd + onz_row] = mat_j[col];
695:         ba[rowstart_offd + onz_row] = mat_a[col];
696:         onz_row++;
697:       }
698:     }
699:     ailen[j] = dnz_row;
700:     bilen[j] = onz_row;
701:   }
702:   PetscFunctionReturn(PETSC_SUCCESS);
703: }

705: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
706: {
707:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
708:   PetscInt     i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
709:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
710:   PetscBool    roworiented = aij->roworiented;
711:   PetscScalar *value;

713:   PetscFunctionBegin;
714:   for (i = 0; i < m; i++) {
715:     if (idxm[i] < 0) continue; /* negative row */
716:     PetscCheck(idxm[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, idxm[i], mat->rmap->N - 1);
717:     PetscCheck(idxm[i] >= rstart && idxm[i] < rend, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only local values currently supported, row requested %" PetscInt_FMT " range [%" PetscInt_FMT " %" PetscInt_FMT ")", idxm[i], rstart, rend);
718:     row = idxm[i] - rstart;
719:     for (j = 0; j < n; j++) {
720:       if (idxn[j] < 0) continue; /* negative column */
721:       PetscCheck(idxn[j] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, idxn[j], mat->cmap->N - 1);
722:       value = roworiented ? &v[j + i * n] : &v[i + j * m];
723:       if (idxn[j] >= cstart && idxn[j] < cend) {
724:         col = idxn[j] - cstart;
725:         PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, value));
726:       } else {
727:         if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
728: #if PetscDefined(USE_CTABLE)
729:         PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
730:         col--;
731: #else
732:         col = aij->colmap[idxn[j]] - 1;
733: #endif
734:         if (col < 0 || aij->garray[col] != idxn[j]) *value = 0.0;
735:         else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, value));
736:       }
737:     }
738:   }
739:   PetscFunctionReturn(PETSC_SUCCESS);
740: }

742: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
743: {
744:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
745:   PetscInt    nstash, reallocs;

747:   PetscFunctionBegin;
748:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

750:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
751:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
752:   PetscCall(PetscInfo(mat, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
753:   PetscFunctionReturn(PETSC_SUCCESS);
754: }

756: PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat, MatAssemblyType mode)
757: {
758:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
759:   PetscMPIInt  n;
760:   PetscInt     i, j, rstart, ncols, flg;
761:   PetscInt    *row, *col;
762:   PetscBool    all_assembled;
763:   PetscScalar *val;

765:   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */

767:   PetscFunctionBegin;
768:   if (!aij->donotstash && !mat->nooffprocentries) {
769:     while (1) {
770:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
771:       if (!flg) break;

773:       for (i = 0; i < n;) {
774:         /* Now identify the consecutive vals belonging to the same row */
775:         for (j = i, rstart = row[j]; j < n; j++) {
776:           if (row[j] != rstart) break;
777:         }
778:         if (j < n) ncols = j - i;
779:         else ncols = n - i;
780:         /* Now assemble all these values with a single function call */
781:         PetscCall(MatSetValues_MPIAIJ(mat, 1, row + i, ncols, col + i, val + i, mat->insertmode));
782:         i = j;
783:       }
784:     }
785:     PetscCall(MatStashScatterEnd_Private(&mat->stash));
786:   }
787: #if PetscDefined(HAVE_DEVICE)
788:   if (mat->offloadmask == PETSC_OFFLOAD_CPU) aij->A->offloadmask = PETSC_OFFLOAD_CPU;
789:   /* We call MatBindToCPU() on aij->A and aij->B here, because if MatBindToCPU_MPIAIJ() is called before assembly, it cannot bind these. */
790:   if (mat->boundtocpu) {
791:     PetscCall(MatBindToCPU(aij->A, PETSC_TRUE));
792:     PetscCall(MatBindToCPU(aij->B, PETSC_TRUE));
793:   }
794: #endif
795:   PetscCall(MatAssemblyBegin(aij->A, mode));
796:   PetscCall(MatAssemblyEnd(aij->A, mode));

798:   /* determine if any process has disassembled, if so we must
799:      also disassemble ourself, in order that we may reassemble. */
800:   /*
801:      if nonzero structure of submatrix B cannot change then we know that
802:      no process disassembled thus we can skip this stuff
803:   */
804:   if (!((Mat_SeqAIJ *)aij->B->data)->nonew) {
805:     PetscCallMPI(MPIU_Allreduce(&mat->was_assembled, &all_assembled, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
806:     if (mat->was_assembled && !all_assembled) { /* mat on this rank has reduced off-diag B with local col ids, but globally it does not */
807:       PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
808:     }
809:   }
810:   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) PetscCall(MatSetUpMultiply_MPIAIJ(mat));
811:   PetscCall(MatSetOption(aij->B, MAT_USE_INODES, PETSC_FALSE));
812: #if PetscDefined(HAVE_DEVICE)
813:   if (mat->offloadmask == PETSC_OFFLOAD_CPU && aij->B->offloadmask != PETSC_OFFLOAD_UNALLOCATED) aij->B->offloadmask = PETSC_OFFLOAD_CPU;
814: #endif
815:   PetscCall(MatAssemblyBegin(aij->B, mode));
816:   PetscCall(MatAssemblyEnd(aij->B, mode));

818:   PetscCall(PetscFree2(aij->rowvalues, aij->rowindices));

820:   aij->rowvalues = NULL;

822:   PetscCall(VecDestroy(&aij->diag));

824:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
825:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)aij->A->data)->nonew) {
826:     mat->nonzerostate = aij->A->nonzerostate + aij->B->nonzerostate;
827:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
828:   }
829: #if PetscDefined(HAVE_DEVICE)
830:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
831: #endif
832:   PetscFunctionReturn(PETSC_SUCCESS);
833: }

835: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
836: {
837:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

839:   PetscFunctionBegin;
840:   PetscCall(MatZeroEntries(l->A));
841:   PetscCall(MatZeroEntries(l->B));
842:   PetscFunctionReturn(PETSC_SUCCESS);
843: }

845: static PetscErrorCode MatZeroRows_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
846: {
847:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)A->data;
848:   PetscInt   *lrows;
849:   PetscInt    r, len;
850:   PetscBool   cong;

852:   PetscFunctionBegin;
853:   /* get locally owned rows */
854:   PetscCall(MatZeroRowsMapLocal_Private(A, N, rows, &len, &lrows));
855:   PetscCall(MatHasCongruentLayouts(A, &cong));
856:   /* fix right-hand side if needed */
857:   if (x && b) {
858:     const PetscScalar *xx;
859:     PetscScalar       *bb;

861:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
862:     PetscCall(VecGetArrayRead(x, &xx));
863:     PetscCall(VecGetArray(b, &bb));
864:     for (r = 0; r < len; ++r) bb[lrows[r]] = diag * xx[lrows[r]];
865:     PetscCall(VecRestoreArrayRead(x, &xx));
866:     PetscCall(VecRestoreArray(b, &bb));
867:   }

869:   if (diag != 0.0 && cong) {
870:     PetscCall(MatZeroRows(mat->A, len, lrows, diag, NULL, NULL));
871:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
872:   } else if (diag != 0.0) { /* non-square or non congruent layouts -> if keepnonzeropattern is false, we allow for new insertion */
873:     Mat_SeqAIJ *aijA = (Mat_SeqAIJ *)mat->A->data;
874:     Mat_SeqAIJ *aijB = (Mat_SeqAIJ *)mat->B->data;
875:     PetscInt    nnwA, nnwB;
876:     PetscBool   nnzA, nnzB;

878:     nnwA = aijA->nonew;
879:     nnwB = aijB->nonew;
880:     nnzA = aijA->keepnonzeropattern;
881:     nnzB = aijB->keepnonzeropattern;
882:     if (!nnzA) {
883:       PetscCall(PetscInfo(mat->A, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on diagonal block.\n"));
884:       aijA->nonew = 0;
885:     }
886:     if (!nnzB) {
887:       PetscCall(PetscInfo(mat->B, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on off-diagonal block.\n"));
888:       aijB->nonew = 0;
889:     }
890:     /* Must zero here before the next loop */
891:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
892:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
893:     for (r = 0; r < len; ++r) {
894:       const PetscInt row = lrows[r] + A->rmap->rstart;
895:       if (row >= A->cmap->N) continue;
896:       PetscCall(MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES));
897:     }
898:     aijA->nonew = nnwA;
899:     aijB->nonew = nnwB;
900:   } else {
901:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
902:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
903:   }
904:   PetscCall(PetscFree(lrows));
905:   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
906:   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

908:   /* only change matrix nonzero state if pattern was allowed to be changed */
909:   if (!((Mat_SeqAIJ *)mat->A->data)->keepnonzeropattern || !((Mat_SeqAIJ *)mat->A->data)->nonew) {
910:     A->nonzerostate = mat->A->nonzerostate + mat->B->nonzerostate;
911:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
912:   }
913:   PetscFunctionReturn(PETSC_SUCCESS);
914: }

916: static PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
917: {
918:   Mat_MPIAIJ        *l = (Mat_MPIAIJ *)A->data;
919:   PetscInt           n = A->rmap->n;
920:   PetscInt           i, j, r, m, len = 0;
921:   PetscInt          *lrows, *owners = A->rmap->range;
922:   PetscMPIInt        p = 0;
923:   PetscSFNode       *rrows;
924:   PetscSF            sf;
925:   const PetscScalar *xx;
926:   PetscScalar       *bb, *mask, *aij_a;
927:   Vec                xmask, lmask;
928:   Mat_SeqAIJ        *aij = (Mat_SeqAIJ *)l->B->data;
929:   const PetscInt    *aj, *ii, *ridx;
930:   PetscScalar       *aa;

932:   PetscFunctionBegin;
933:   /* Create SF where leaves are input rows and roots are owned rows */
934:   PetscCall(PetscMalloc1(n, &lrows));
935:   for (r = 0; r < n; ++r) lrows[r] = -1;
936:   PetscCall(PetscMalloc1(N, &rrows));
937:   for (r = 0; r < N; ++r) {
938:     const PetscInt idx = rows[r];
939:     PetscCheck(idx >= 0 && A->rmap->N > idx, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row %" PetscInt_FMT " out of range [0,%" PetscInt_FMT ")", idx, A->rmap->N);
940:     if (idx < owners[p] || owners[p + 1] <= idx) { /* short-circuit the search if the last p owns this row too */
941:       PetscCall(PetscLayoutFindOwner(A->rmap, idx, &p));
942:     }
943:     rrows[r].rank  = p;
944:     rrows[r].index = rows[r] - owners[p];
945:   }
946:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
947:   PetscCall(PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER));
948:   /* Collect flags for rows to be zeroed */
949:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
950:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
951:   PetscCall(PetscSFDestroy(&sf));
952:   /* Compress and put in row numbers */
953:   for (r = 0; r < n; ++r)
954:     if (lrows[r] >= 0) lrows[len++] = r;
955:   /* zero diagonal part of matrix */
956:   PetscCall(MatZeroRowsColumns(l->A, len, lrows, diag, x, b));
957:   /* handle off-diagonal part of matrix */
958:   PetscCall(MatCreateVecs(A, &xmask, NULL));
959:   PetscCall(VecDuplicate(l->lvec, &lmask));
960:   PetscCall(VecGetArray(xmask, &bb));
961:   for (i = 0; i < len; i++) bb[lrows[i]] = 1;
962:   PetscCall(VecRestoreArray(xmask, &bb));
963:   PetscCall(VecScatterBegin(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
964:   PetscCall(VecScatterEnd(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
965:   PetscCall(VecDestroy(&xmask));
966:   if (x && b) { /* this code is buggy when the row and column layout don't match */
967:     PetscBool cong;

969:     PetscCall(MatHasCongruentLayouts(A, &cong));
970:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
971:     PetscCall(VecScatterBegin(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
972:     PetscCall(VecScatterEnd(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
973:     PetscCall(VecGetArrayRead(l->lvec, &xx));
974:     PetscCall(VecGetArray(b, &bb));
975:   }
976:   PetscCall(VecGetArray(lmask, &mask));
977:   /* remove zeroed rows of off-diagonal matrix */
978:   PetscCall(MatSeqAIJGetArray(l->B, &aij_a));
979:   ii = aij->i;
980:   for (i = 0; i < len; i++) PetscCall(PetscArrayzero(PetscSafePointerPlusOffset(aij_a, ii[lrows[i]]), ii[lrows[i] + 1] - ii[lrows[i]]));
981:   /* loop over all elements of off process part of matrix zeroing removed columns*/
982:   if (aij->compressedrow.use) {
983:     m    = aij->compressedrow.nrows;
984:     ii   = aij->compressedrow.i;
985:     ridx = aij->compressedrow.rindex;
986:     for (i = 0; i < m; i++) {
987:       n  = ii[i + 1] - ii[i];
988:       aj = aij->j + ii[i];
989:       aa = aij_a + ii[i];

991:       for (j = 0; j < n; j++) {
992:         if (PetscAbsScalar(mask[*aj])) {
993:           if (b) bb[*ridx] -= *aa * xx[*aj];
994:           *aa = 0.0;
995:         }
996:         aa++;
997:         aj++;
998:       }
999:       ridx++;
1000:     }
1001:   } else { /* do not use compressed row format */
1002:     m = l->B->rmap->n;
1003:     for (i = 0; i < m; i++) {
1004:       n  = ii[i + 1] - ii[i];
1005:       aj = aij->j + ii[i];
1006:       aa = aij_a + ii[i];
1007:       for (j = 0; j < n; j++) {
1008:         if (PetscAbsScalar(mask[*aj])) {
1009:           if (b) bb[i] -= *aa * xx[*aj];
1010:           *aa = 0.0;
1011:         }
1012:         aa++;
1013:         aj++;
1014:       }
1015:     }
1016:   }
1017:   if (x && b) {
1018:     PetscCall(VecRestoreArray(b, &bb));
1019:     PetscCall(VecRestoreArrayRead(l->lvec, &xx));
1020:   }
1021:   PetscCall(MatSeqAIJRestoreArray(l->B, &aij_a));
1022:   PetscCall(VecRestoreArray(lmask, &mask));
1023:   PetscCall(VecDestroy(&lmask));
1024:   PetscCall(PetscFree(lrows));

1026:   /* only change matrix nonzero state if pattern was allowed to be changed */
1027:   if (!((Mat_SeqAIJ *)l->A->data)->nonew) {
1028:     A->nonzerostate = l->A->nonzerostate + l->B->nonzerostate;
1029:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1030:   }
1031:   PetscFunctionReturn(PETSC_SUCCESS);
1032: }

1034: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1035: {
1036:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1037:   PetscInt    nt;
1038:   VecScatter  Mvctx = a->Mvctx;

1040:   PetscFunctionBegin;
1041:   PetscCall(VecGetLocalSize(xx, &nt));
1042:   PetscCheck(nt == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Incompatible partition of A (%" PetscInt_FMT ") and xx (%" PetscInt_FMT ")", A->cmap->n, nt);
1043:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1044:   PetscUseTypeMethod(a->A, mult, xx, yy);
1045:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1046:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1047:   PetscFunctionReturn(PETSC_SUCCESS);
1048: }

1050: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1051: {
1052:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1054:   PetscFunctionBegin;
1055:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1056:   PetscFunctionReturn(PETSC_SUCCESS);
1057: }

1059: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1060: {
1061:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1062:   VecScatter  Mvctx = a->Mvctx;

1064:   PetscFunctionBegin;
1065:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1066:   PetscUseTypeMethod(a->A, multadd, xx, yy, zz);
1067:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1068:   PetscUseTypeMethod(a->B, multadd, a->lvec, zz, zz);
1069:   PetscFunctionReturn(PETSC_SUCCESS);
1070: }

1072: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1073: {
1074:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1076:   PetscFunctionBegin;
1077:   /* do nondiagonal part */
1078:   PetscUseTypeMethod(a->B, multtranspose, xx, a->lvec);
1079:   /* do local part */
1080:   PetscUseTypeMethod(a->A, multtranspose, xx, yy);
1081:   /* add partial results together */
1082:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1083:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1084:   PetscFunctionReturn(PETSC_SUCCESS);
1085: }

1087: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1088: {
1089:   MPI_Comm    comm;
1090:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1091:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1092:   IS          Me, Notme;
1093:   PetscInt    M, N, first, last, *notme, i;
1094:   PetscMPIInt size;

1096:   PetscFunctionBegin;
1097:   /* Easy test: symmetric diagonal block */
1098:   PetscCall(MatIsTranspose(Adia, Bdia, tol, f));
1099:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, f, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1100:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1101:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1102:   PetscCallMPI(MPI_Comm_size(comm, &size));
1103:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1105:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1106:   PetscCall(MatGetSize(Amat, &M, &N));
1107:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1108:   PetscCall(PetscMalloc1(N - last + first, &notme));
1109:   for (i = 0; i < first; i++) notme[i] = i;
1110:   for (i = last; i < M; i++) notme[i - last + first] = i;
1111:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1112:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1113:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1114:   Aoff = Aoffs[0];
1115:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1116:   Boff = Boffs[0];
1117:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1118:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1119:   PetscCall(MatDestroyMatrices(1, &Boffs));
1120:   PetscCall(ISDestroy(&Me));
1121:   PetscCall(ISDestroy(&Notme));
1122:   PetscCall(PetscFree(notme));
1123:   PetscFunctionReturn(PETSC_SUCCESS);
1124: }

1126: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1127: {
1128:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1130:   PetscFunctionBegin;
1131:   /* do nondiagonal part */
1132:   PetscUseTypeMethod(a->B, multtranspose, xx, a->lvec);
1133:   /* do local part */
1134:   PetscUseTypeMethod(a->A, multtransposeadd, xx, yy, zz);
1135:   /* add partial results together */
1136:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1137:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1138:   PetscFunctionReturn(PETSC_SUCCESS);
1139: }

1141: /*
1142:   This only works correctly for square matrices where the subblock A->A is the
1143:    diagonal block
1144: */
1145: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1146: {
1147:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1149:   PetscFunctionBegin;
1150:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1151:   PetscCheck(A->rmap->rstart == A->cmap->rstart && A->rmap->rend == A->cmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "row partition must equal col partition");
1152:   PetscCall(MatGetDiagonal(a->A, v));
1153:   PetscFunctionReturn(PETSC_SUCCESS);
1154: }

1156: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1157: {
1158:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1160:   PetscFunctionBegin;
1161:   PetscCall(MatScale(a->A, aa));
1162:   PetscCall(MatScale(a->B, aa));
1163:   PetscFunctionReturn(PETSC_SUCCESS);
1164: }

1166: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1167: {
1168:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1169:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1170:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1171:   const PetscInt    *garray = aij->garray;
1172:   const PetscScalar *aa, *ba;
1173:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1174:   PetscInt64         nz, hnz;
1175:   PetscInt          *rowlens;
1176:   PetscInt          *colidxs;
1177:   PetscScalar       *matvals;
1178:   PetscMPIInt        rank;

1180:   PetscFunctionBegin;
1181:   PetscCall(PetscViewerSetUp(viewer));

1183:   M  = mat->rmap->N;
1184:   N  = mat->cmap->N;
1185:   m  = mat->rmap->n;
1186:   rs = mat->rmap->rstart;
1187:   cs = mat->cmap->rstart;
1188:   nz = A->nz + B->nz;

1190:   /* write matrix header */
1191:   header[0] = MAT_FILE_CLASSID;
1192:   header[1] = M;
1193:   header[2] = N;
1194:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1195:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1196:   if (rank == 0) PetscCall(PetscIntCast(hnz, &header[3]));
1197:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1199:   /* fill in and store row lengths  */
1200:   PetscCall(PetscMalloc1(m, &rowlens));
1201:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1202:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1203:   PetscCall(PetscFree(rowlens));

1205:   /* fill in and store column indices */
1206:   PetscCall(PetscMalloc1(nz, &colidxs));
1207:   for (cnt = 0, i = 0; i < m; i++) {
1208:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1209:       if (garray[B->j[jb]] > cs) break;
1210:       colidxs[cnt++] = garray[B->j[jb]];
1211:     }
1212:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1213:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1214:   }
1215:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1216:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1217:   PetscCall(PetscFree(colidxs));

1219:   /* fill in and store nonzero values */
1220:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1221:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1222:   PetscCall(PetscMalloc1(nz, &matvals));
1223:   for (cnt = 0, i = 0; i < m; i++) {
1224:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1225:       if (garray[B->j[jb]] > cs) break;
1226:       matvals[cnt++] = ba[jb];
1227:     }
1228:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1229:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1230:   }
1231:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1232:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1233:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1234:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1235:   PetscCall(PetscFree(matvals));

1237:   /* write block size option to the viewer's .info file */
1238:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1239:   PetscFunctionReturn(PETSC_SUCCESS);
1240: }

1242: #include <petscdraw.h>
1243: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1244: {
1245:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1246:   PetscMPIInt       rank = aij->rank, size = aij->size;
1247:   PetscBool         isdraw, isascii, isbinary;
1248:   PetscViewer       sviewer;
1249:   PetscViewerFormat format;

1251:   PetscFunctionBegin;
1252:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1253:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1254:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1255:   if (isascii) {
1256:     PetscCall(PetscViewerGetFormat(viewer, &format));
1257:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1258:       PetscInt i, nmax = 0, nmin = PETSC_INT_MAX, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)aij->A->data)->nz + ((Mat_SeqAIJ *)aij->B->data)->nz;
1259:       PetscCall(PetscMalloc1(size, &nz));
1260:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1261:       for (i = 0; i < size; i++) {
1262:         nmax = PetscMax(nmax, nz[i]);
1263:         nmin = PetscMin(nmin, nz[i]);
1264:         navg += nz[i];
1265:       }
1266:       PetscCall(PetscFree(nz));
1267:       navg = navg / size;
1268:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1269:       PetscFunctionReturn(PETSC_SUCCESS);
1270:     }
1271:     PetscCall(PetscViewerGetFormat(viewer, &format));
1272:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1273:       MatInfo   info;
1274:       PetscInt *inodes = NULL;

1276:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1277:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1278:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1279:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1280:       if (!inodes) {
1281:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] Local rows %" PetscInt_FMT " nz %" PetscInt_FMT " nz alloced %" PetscInt_FMT " mem %g, not using I-node routines\n", rank, mat->rmap->n, (PetscInt)info.nz_used, (PetscInt)info.nz_allocated,
1282:                                                      info.memory));
1283:       } else {
1284:         PetscCall(
1285:           PetscViewerASCIISynchronizedPrintf(viewer, "[%d] Local rows %" PetscInt_FMT " nz %" PetscInt_FMT " nz alloced %" PetscInt_FMT " mem %g, using I-node routines\n", rank, mat->rmap->n, (PetscInt)info.nz_used, (PetscInt)info.nz_allocated, info.memory));
1286:       }
1287:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1288:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1289:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1290:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1291:       PetscCall(PetscViewerFlush(viewer));
1292:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1293:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1294:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1295:       PetscFunctionReturn(PETSC_SUCCESS);
1296:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1297:       PetscInt inodecount, inodelimit, *inodes;
1298:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1299:       if (inodes) {
1300:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1301:       } else {
1302:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1303:       }
1304:       PetscFunctionReturn(PETSC_SUCCESS);
1305:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1306:       PetscFunctionReturn(PETSC_SUCCESS);
1307:     }
1308:   } else if (isbinary) {
1309:     if (size == 1) {
1310:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1311:       PetscCall(MatView(aij->A, viewer));
1312:     } else {
1313:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1314:     }
1315:     PetscFunctionReturn(PETSC_SUCCESS);
1316:   } else if (isascii && size == 1) {
1317:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1318:     PetscCall(MatView(aij->A, viewer));
1319:     PetscFunctionReturn(PETSC_SUCCESS);
1320:   } else if (isdraw) {
1321:     PetscDraw draw;
1322:     PetscBool isnull;
1323:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1324:     PetscCall(PetscDrawIsNull(draw, &isnull));
1325:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1326:   }

1328:   { /* assemble the entire matrix onto first process */
1329:     Mat A, Av;
1330:     IS  isrow, iscol;

1332:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1333:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1334:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1335:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1336:     PetscCall(ISDestroy(&iscol));
1337:     PetscCall(ISDestroy(&isrow));
1338:     /*
1339:        Everyone has to call to draw the matrix since the graphics waits are
1340:        synchronized across all processors that share the PetscDraw object
1341:     */
1342:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1343:     if (rank == 0) {
1344:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1345:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1346:     }
1347:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1348:     PetscCall(MatDestroy(&A));
1349:   }
1350:   PetscFunctionReturn(PETSC_SUCCESS);
1351: }

1353: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1354: {
1355:   PetscBool isascii, isdraw, issocket, isbinary;

1357:   PetscFunctionBegin;
1358:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
1359:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1360:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1361:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1362:   if (isascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1363:   PetscFunctionReturn(PETSC_SUCCESS);
1364: }

1366: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1367: {
1368:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1369:   Vec         bb1 = NULL;
1370:   PetscBool   hasop;

1372:   PetscFunctionBegin;
1373:   if (flag == SOR_APPLY_UPPER) {
1374:     PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1375:     PetscFunctionReturn(PETSC_SUCCESS);
1376:   }

1378:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1380:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1381:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1382:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1383:       its--;
1384:     }

1386:     while (its--) {
1387:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1388:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1390:       /* update rhs: bb1 = bb - B*x */
1391:       PetscCall(VecScale(mat->lvec, -1.0));
1392:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1394:       /* local sweep */
1395:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx);
1396:     }
1397:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1398:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1399:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1400:       its--;
1401:     }
1402:     while (its--) {
1403:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1404:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1406:       /* update rhs: bb1 = bb - B*x */
1407:       PetscCall(VecScale(mat->lvec, -1.0));
1408:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1410:       /* local sweep */
1411:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx);
1412:     }
1413:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1414:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1415:       PetscUseTypeMethod(mat->A, sor, bb, omega, flag, fshift, lits, 1, xx);
1416:       its--;
1417:     }
1418:     while (its--) {
1419:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1420:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1422:       /* update rhs: bb1 = bb - B*x */
1423:       PetscCall(VecScale(mat->lvec, -1.0));
1424:       PetscUseTypeMethod(mat->B, multadd, mat->lvec, bb, bb1);

1426:       /* local sweep */
1427:       PetscUseTypeMethod(mat->A, sor, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx);
1428:     }
1429:   } else if (flag & SOR_EISENSTAT) {
1430:     Vec xx1;

1432:     PetscCall(VecDuplicate(bb, &xx1));
1433:     PetscUseTypeMethod(mat->A, sor, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx);

1435:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1436:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1437:     if (!mat->diag) {
1438:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1439:       PetscCall(MatGetDiagonal(matin, mat->diag));
1440:     }
1441:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1442:     if (hasop) PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1443:     else PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1444:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1446:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1448:     /* local sweep */
1449:     PetscUseTypeMethod(mat->A, sor, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1);
1450:     PetscCall(VecAXPY(xx, 1.0, xx1));
1451:     PetscCall(VecDestroy(&xx1));
1452:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1454:   PetscCall(VecDestroy(&bb1));

1456:   matin->factorerrortype = mat->A->factorerrortype;
1457:   PetscFunctionReturn(PETSC_SUCCESS);
1458: }

1460: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1461: {
1462:   Mat             aA, aB, Aperm;
1463:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1464:   PetscScalar    *aa, *ba;
1465:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1466:   PetscSF         rowsf, sf;
1467:   IS              parcolp = NULL;
1468:   PetscBool       done;

1470:   PetscFunctionBegin;
1471:   PetscCall(MatGetLocalSize(A, &m, &n));
1472:   PetscCall(ISGetIndices(rowp, &rwant));
1473:   PetscCall(ISGetIndices(colp, &cwant));
1474:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1476:   /* Invert row permutation to find out where my rows should go */
1477:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1478:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1479:   PetscCall(PetscSFSetFromOptions(rowsf));
1480:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1481:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1482:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1484:   /* Invert column permutation to find out where my columns should go */
1485:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1486:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1487:   PetscCall(PetscSFSetFromOptions(sf));
1488:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1489:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1490:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1491:   PetscCall(PetscSFDestroy(&sf));

1493:   PetscCall(ISRestoreIndices(rowp, &rwant));
1494:   PetscCall(ISRestoreIndices(colp, &cwant));
1495:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1497:   /* Find out where my gcols should go */
1498:   PetscCall(MatGetSize(aB, NULL, &ng));
1499:   PetscCall(PetscMalloc1(ng, &gcdest));
1500:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1501:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1502:   PetscCall(PetscSFSetFromOptions(sf));
1503:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1504:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1505:   PetscCall(PetscSFDestroy(&sf));

1507:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1508:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1509:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1510:   for (i = 0; i < m; i++) {
1511:     PetscInt    row = rdest[i];
1512:     PetscMPIInt rowner;
1513:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1514:     for (j = ai[i]; j < ai[i + 1]; j++) {
1515:       PetscInt    col = cdest[aj[j]];
1516:       PetscMPIInt cowner;
1517:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1518:       if (rowner == cowner) dnnz[i]++;
1519:       else onnz[i]++;
1520:     }
1521:     for (j = bi[i]; j < bi[i + 1]; j++) {
1522:       PetscInt    col = gcdest[bj[j]];
1523:       PetscMPIInt cowner;
1524:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1525:       if (rowner == cowner) dnnz[i]++;
1526:       else onnz[i]++;
1527:     }
1528:   }
1529:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1530:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1531:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1532:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1533:   PetscCall(PetscSFDestroy(&rowsf));

1535:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1536:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1537:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1538:   for (i = 0; i < m; i++) {
1539:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1540:     PetscInt  rowlen;
1541:     rowlen = ai[i + 1] - ai[i];
1542:     for (PetscInt j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1543:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1544:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1545:     }
1546:     rowlen = bi[i + 1] - bi[i];
1547:     for (PetscInt j0 = j = 0; j < rowlen; j0 = j) {
1548:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1549:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1550:     }
1551:   }
1552:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1553:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1554:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1555:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1556:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1557:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1558:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1559:   PetscCall(PetscFree3(work, rdest, cdest));
1560:   PetscCall(PetscFree(gcdest));
1561:   if (parcolp) PetscCall(ISDestroy(&colp));
1562:   *B = Aperm;
1563:   PetscFunctionReturn(PETSC_SUCCESS);
1564: }

1566: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1567: {
1568:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1570:   PetscFunctionBegin;
1571:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1572:   if (ghosts) *ghosts = aij->garray;
1573:   PetscFunctionReturn(PETSC_SUCCESS);
1574: }

1576: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1577: {
1578:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1579:   Mat            A = mat->A, B = mat->B;
1580:   PetscLogDouble irecv[5];

1582:   PetscFunctionBegin;
1583:   info->block_size = 1.0;
1584:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1586:   irecv[0] = info->nz_used;
1587:   irecv[1] = info->nz_allocated;
1588:   irecv[2] = info->nz_unneeded;
1589:   irecv[3] = info->memory;
1590:   irecv[4] = info->mallocs;

1592:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1594:   irecv[0] += info->nz_used;
1595:   irecv[1] += info->nz_allocated;
1596:   irecv[2] += info->nz_unneeded;
1597:   irecv[3] += info->memory;
1598:   irecv[4] += info->mallocs;
1599:   if (flag == MAT_LOCAL) {
1600:     info->nz_used      = irecv[0];
1601:     info->nz_allocated = irecv[1];
1602:     info->nz_unneeded  = irecv[2];
1603:     info->memory       = irecv[3];
1604:     info->mallocs      = irecv[4];
1605:   } else if (flag == MAT_GLOBAL_MAX) {
1606:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, PetscObjectComm((PetscObject)matin)));

1608:     info->nz_used      = irecv[0];
1609:     info->nz_allocated = irecv[1];
1610:     info->nz_unneeded  = irecv[2];
1611:     info->memory       = irecv[3];
1612:     info->mallocs      = irecv[4];
1613:   } else if (flag == MAT_GLOBAL_SUM) {
1614:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1616:     info->nz_used      = irecv[0];
1617:     info->nz_allocated = irecv[1];
1618:     info->nz_unneeded  = irecv[2];
1619:     info->memory       = irecv[3];
1620:     info->mallocs      = irecv[4];
1621:   }
1622:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1623:   info->fill_ratio_needed = 0;
1624:   info->factor_mallocs    = 0;
1625:   PetscFunctionReturn(PETSC_SUCCESS);
1626: }

1628: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1629: {
1630:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1632:   PetscFunctionBegin;
1633:   switch (op) {
1634:   case MAT_NEW_NONZERO_LOCATIONS:
1635:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1636:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1637:   case MAT_KEEP_NONZERO_PATTERN:
1638:   case MAT_NEW_NONZERO_LOCATION_ERR:
1639:   case MAT_USE_INODES:
1640:   case MAT_IGNORE_ZERO_ENTRIES:
1641:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1642:   case MAT_ROW_ORIENTED:
1643:     MatCheckPreallocated(A, 1);
1644:     if (op == MAT_ROW_ORIENTED) a->roworiented = flg;
1645:     PetscCall(MatSetOption(a->A, op, flg));
1646:     PetscCall(MatSetOption(a->B, op, flg));
1647:     break;
1648:   case MAT_STRUCTURE_ONLY:
1649:     if (a->A) PetscCall(MatSetOption(a->A, op, flg));
1650:     if (a->B) PetscCall(MatSetOption(a->B, op, flg));
1651:     break;
1652:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1653:     a->donotstash = flg;
1654:     break;
1655:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1656:   case MAT_SPD:
1657:   case MAT_SYMMETRIC:
1658:   case MAT_STRUCTURALLY_SYMMETRIC:
1659:   case MAT_HERMITIAN:
1660:   case MAT_SYMMETRY_ETERNAL:
1661:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1662:   case MAT_SPD_ETERNAL:
1663:     /* if the diagonal matrix is square it inherits some of the properties above */
1664:     if (a->A && A->rmap->n == A->cmap->n) PetscCall(MatSetOption(a->A, op, flg));
1665:     break;
1666:   case MAT_SUBMAT_SINGLEIS:
1667:     A->submat_singleis = flg;
1668:     break;
1669:   default:
1670:     break;
1671:   }
1672:   PetscFunctionReturn(PETSC_SUCCESS);
1673: }

1675: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1676: {
1677:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1678:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1679:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1680:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1681:   PetscInt    *cmap, *idx_p;

1683:   PetscFunctionBegin;
1684:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1685:   mat->getrowactive = PETSC_TRUE;

1687:   if ((!mat->rowindices && (idx || v)) || (!mat->rowvalues && v)) {
1688:     /*
1689:         allocate enough space to hold information from the longest row.
1690:     */
1691:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1692:     PetscInt    max = 1, tmp;
1693:     for (i = 0; i < matin->rmap->n; i++) {
1694:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1695:       if (max < tmp) max = tmp;
1696:     }
1697:     PetscCall(PetscFree2(mat->rowvalues, mat->rowindices));
1698:     PetscCall(PetscMalloc2(v ? max : 0, &mat->rowvalues, max, &mat->rowindices));
1699:   }

1701:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1702:   lrow = row - rstart;

1704:   pvA = &vworkA;
1705:   pcA = &cworkA;
1706:   pvB = &vworkB;
1707:   pcB = &cworkB;
1708:   if (!v) {
1709:     pvA = NULL;
1710:     pvB = NULL;
1711:   }
1712:   if (!idx) {
1713:     pcA = NULL;
1714:     if (!v) pcB = NULL;
1715:   }
1716:   PetscUseTypeMethod(mat->A, getrow, lrow, &nzA, pcA, pvA);
1717:   PetscUseTypeMethod(mat->B, getrow, lrow, &nzB, pcB, pvB);
1718:   nztot = nzA + nzB;

1720:   cmap = mat->garray;
1721:   if (v || idx) {
1722:     if (nztot) {
1723:       /* Sort by increasing column numbers, assuming A and B already sorted */
1724:       PetscInt imark = -1;
1725:       if (v) {
1726:         *v = v_p = mat->rowvalues;
1727:         for (i = 0; i < nzB; i++) {
1728:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1729:           else break;
1730:         }
1731:         imark = i;
1732:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1733:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1734:       }
1735:       if (idx) {
1736:         *idx = idx_p = mat->rowindices;
1737:         if (imark > -1) {
1738:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1739:         } else {
1740:           for (i = 0; i < nzB; i++) {
1741:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1742:             else break;
1743:           }
1744:           imark = i;
1745:         }
1746:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1747:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1748:       }
1749:     } else {
1750:       if (idx) *idx = NULL;
1751:       if (v) *v = NULL;
1752:     }
1753:   }
1754:   *nz = nztot;
1755:   PetscUseTypeMethod(mat->A, restorerow, lrow, &nzA, pcA, pvA);
1756:   PetscUseTypeMethod(mat->B, restorerow, lrow, &nzB, pcB, pvB);
1757:   PetscFunctionReturn(PETSC_SUCCESS);
1758: }

1760: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1761: {
1762:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1764:   PetscFunctionBegin;
1765:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1766:   aij->getrowactive = PETSC_FALSE;
1767:   PetscFunctionReturn(PETSC_SUCCESS);
1768: }

1770: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1771: {
1772:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1773:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1774:   PetscInt         i, j;
1775:   PetscReal        sum = 0.0;
1776:   const MatScalar *v, *amata, *bmata;

1778:   PetscFunctionBegin;
1779:   if (aij->size == 1) {
1780:     PetscCall(MatNorm(aij->A, type, norm));
1781:   } else {
1782:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1783:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1784:     if (type == NORM_FROBENIUS) {
1785:       v = amata;
1786:       for (i = 0; i < amat->nz; i++) {
1787:         sum += PetscRealPart(PetscConj(*v) * (*v));
1788:         v++;
1789:       }
1790:       v = bmata;
1791:       for (i = 0; i < bmat->nz; i++) {
1792:         sum += PetscRealPart(PetscConj(*v) * (*v));
1793:         v++;
1794:       }
1795:       PetscCallMPI(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1796:       *norm = PetscSqrtReal(*norm);
1797:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1798:     } else if (type == NORM_1) { /* max column norm */
1799:       Vec          col, bcol;
1800:       PetscScalar *array;
1801:       PetscInt    *jj, *garray = aij->garray;

1803:       PetscCall(MatCreateVecs(mat, &col, NULL));
1804:       PetscCall(VecGetArrayWrite(col, &array));
1805:       v  = amata;
1806:       jj = amat->j;
1807:       for (j = 0; j < amat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1808:       PetscCall(VecRestoreArrayWrite(col, &array));
1809:       PetscCall(MatCreateVecs(aij->B, &bcol, NULL));
1810:       PetscCall(VecGetArrayWrite(bcol, &array));
1811:       v  = bmata;
1812:       jj = bmat->j;
1813:       for (j = 0; j < bmat->nz; j++) array[*jj++] += PetscAbsScalar(*v++);
1814:       PetscCall(VecSetValues(col, aij->B->cmap->n, garray, array, ADD_VALUES));
1815:       PetscCall(VecRestoreArrayWrite(bcol, &array));
1816:       PetscCall(VecDestroy(&bcol));
1817:       PetscCall(VecAssemblyBegin(col));
1818:       PetscCall(VecAssemblyEnd(col));
1819:       PetscCall(VecNorm(col, NORM_INFINITY, norm));
1820:       PetscCall(VecDestroy(&col));
1821:     } else if (type == NORM_INFINITY) { /* max row norm */
1822:       *norm = 0.0;
1823:       for (j = 0; j < aij->A->rmap->n; j++) {
1824:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1825:         sum = 0.0;
1826:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1827:           sum += PetscAbsScalar(*v);
1828:           v++;
1829:         }
1830:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1831:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1832:           sum += PetscAbsScalar(*v);
1833:           v++;
1834:         }
1835:         if (sum > *norm) *norm = sum;
1836:       }
1837:       PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1838:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1839:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1840:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1841:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1842:   }
1843:   PetscFunctionReturn(PETSC_SUCCESS);
1844: }

1846: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1847: {
1848:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1849:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1850:   PetscInt         M = A->rmap->N, N = A->cmap->N, ma, na, mb, nb, row, *cols, *cols_tmp, *B_diag_ilen, i, ncol, A_diag_ncol;
1851:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1852:   Mat              B, A_diag, *B_diag;
1853:   const MatScalar *pbv, *bv;

1855:   PetscFunctionBegin;
1856:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1857:   ma = A->rmap->n;
1858:   na = A->cmap->n;
1859:   mb = a->B->rmap->n;
1860:   nb = a->B->cmap->n;
1861:   ai = Aloc->i;
1862:   aj = Aloc->j;
1863:   bi = Bloc->i;
1864:   bj = Bloc->j;
1865:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1866:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1867:     PetscSFNode         *oloc;
1868:     PETSC_UNUSED PetscSF sf;

1870:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1871:     /* compute d_nnz for preallocation */
1872:     PetscCall(PetscArrayzero(d_nnz, na));
1873:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1874:     /* compute local off-diagonal contributions */
1875:     PetscCall(PetscArrayzero(g_nnz, nb));
1876:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1877:     /* map those to global */
1878:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1879:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1880:     PetscCall(PetscSFSetFromOptions(sf));
1881:     PetscCall(PetscArrayzero(o_nnz, na));
1882:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1883:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1884:     PetscCall(PetscSFDestroy(&sf));

1886:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1887:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1888:     PetscCall(MatSetBlockSizes(B, A->cmap->bs, A->rmap->bs));
1889:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1890:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1891:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1892:   } else {
1893:     B = *matout;
1894:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1895:   }

1897:   b           = (Mat_MPIAIJ *)B->data;
1898:   A_diag      = a->A;
1899:   B_diag      = &b->A;
1900:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1901:   A_diag_ncol = A_diag->cmap->N;
1902:   B_diag_ilen = sub_B_diag->ilen;
1903:   B_diag_i    = sub_B_diag->i;

1905:   /* Set ilen for diagonal of B */
1906:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1908:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1909:   very quickly (=without using MatSetValues), because all writes are local. */
1910:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1911:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1913:   /* copy over the B part */
1914:   PetscCall(PetscMalloc1(bi[mb], &cols));
1915:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1916:   pbv = bv;
1917:   row = A->rmap->rstart;
1918:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1919:   cols_tmp = cols;
1920:   for (i = 0; i < mb; i++) {
1921:     ncol = bi[i + 1] - bi[i];
1922:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1923:     row++;
1924:     if (pbv) pbv += ncol;
1925:     if (cols_tmp) cols_tmp += ncol;
1926:   }
1927:   PetscCall(PetscFree(cols));
1928:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1930:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1931:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1932:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1933:     *matout = B;
1934:   } else {
1935:     PetscCall(MatHeaderMerge(A, &B));
1936:   }
1937:   PetscFunctionReturn(PETSC_SUCCESS);
1938: }

1940: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1941: {
1942:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1943:   Mat         a = aij->A, b = aij->B;
1944:   PetscInt    s1, s2, s3;

1946:   PetscFunctionBegin;
1947:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1948:   if (rr) {
1949:     PetscCall(VecGetLocalSize(rr, &s1));
1950:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
1951:     /* Overlap communication with computation. */
1952:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1953:   }
1954:   if (ll) {
1955:     PetscCall(VecGetLocalSize(ll, &s1));
1956:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
1957:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
1958:   }
1959:   /* scale  the diagonal block */
1960:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

1962:   if (rr) {
1963:     /* Do a scatter end and then right scale the off-diagonal block */
1964:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
1965:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
1966:   }
1967:   PetscFunctionReturn(PETSC_SUCCESS);
1968: }

1970: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
1971: {
1972:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1974:   PetscFunctionBegin;
1975:   PetscCall(MatSetUnfactored(a->A));
1976:   PetscFunctionReturn(PETSC_SUCCESS);
1977: }

1979: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
1980: {
1981:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
1982:   Mat         a, b, c, d;

1984:   PetscFunctionBegin;
1985:   a = matA->A;
1986:   b = matA->B;
1987:   c = matB->A;
1988:   d = matB->B;

1990:   PetscCall(MatEqual(a, c, flag));
1991:   if (*flag) PetscCall(MatEqual(b, d, flag));
1992:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, flag, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
1993:   PetscFunctionReturn(PETSC_SUCCESS);
1994: }

1996: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
1997: {
1998:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1999:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2001:   PetscFunctionBegin;
2002:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2003:   if (str != SAME_NONZERO_PATTERN || A->ops->copy != B->ops->copy) {
2004:     /* because of the column compression in the off-processor part of the matrix a->B,
2005:        the number of columns in a->B and b->B may be different, hence we cannot call
2006:        the MatCopy() directly on the two parts. If need be, we can provide a more
2007:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2008:        then copying the submatrices */
2009:     PetscCall(MatCopy_Basic(A, B, str));
2010:   } else {
2011:     PetscCall(MatCopy(a->A, b->A, str));
2012:     PetscCall(MatCopy(a->B, b->B, str));
2013:   }
2014:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2015:   PetscFunctionReturn(PETSC_SUCCESS);
2016: }

2018: /*
2019:    Computes the number of nonzeros per row needed for preallocation when X and Y
2020:    have different nonzero structure.
2021: */
2022: PetscErrorCode MatAXPYGetPreallocation_MPIX_private(PetscInt m, const PetscInt *xi, const PetscInt *xj, const PetscInt *xltog, const PetscInt *yi, const PetscInt *yj, const PetscInt *yltog, PetscInt *nnz)
2023: {
2024:   PetscInt i, j, k, nzx, nzy;

2026:   PetscFunctionBegin;
2027:   /* Set the number of nonzeros in the new matrix */
2028:   for (i = 0; i < m; i++) {
2029:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2030:     nzx    = xi[i + 1] - xi[i];
2031:     nzy    = yi[i + 1] - yi[i];
2032:     nnz[i] = 0;
2033:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2034:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2035:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2036:       nnz[i]++;
2037:     }
2038:     for (; k < nzy; k++) nnz[i]++;
2039:   }
2040:   PetscFunctionReturn(PETSC_SUCCESS);
2041: }

2043: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2044: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2045: {
2046:   PetscInt    m = Y->rmap->N;
2047:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2048:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2050:   PetscFunctionBegin;
2051:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2052:   PetscFunctionReturn(PETSC_SUCCESS);
2053: }

2055: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2056: {
2057:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2059:   PetscFunctionBegin;
2060:   if (str == SAME_NONZERO_PATTERN) {
2061:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2062:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2063:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2064:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2065:   } else {
2066:     Mat       B;
2067:     PetscInt *nnz_d, *nnz_o;

2069:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2070:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2071:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2072:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2073:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2074:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2075:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2076:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2077:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2078:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2079:     PetscCall(MatHeaderMerge(Y, &B));
2080:     PetscCall(PetscFree(nnz_d));
2081:     PetscCall(PetscFree(nnz_o));
2082:   }
2083:   PetscFunctionReturn(PETSC_SUCCESS);
2084: }

2086: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2088: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2089: {
2090:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2092:   PetscFunctionBegin;
2093:   PetscCall(MatConjugate_SeqAIJ(aij->A));
2094:   PetscCall(MatConjugate_SeqAIJ(aij->B));
2095:   PetscFunctionReturn(PETSC_SUCCESS);
2096: }

2098: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2099: {
2100:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2102:   PetscFunctionBegin;
2103:   PetscCall(MatRealPart(a->A));
2104:   PetscCall(MatRealPart(a->B));
2105:   PetscFunctionReturn(PETSC_SUCCESS);
2106: }

2108: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2109: {
2110:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2112:   PetscFunctionBegin;
2113:   PetscCall(MatImaginaryPart(a->A));
2114:   PetscCall(MatImaginaryPart(a->B));
2115:   PetscFunctionReturn(PETSC_SUCCESS);
2116: }

2118: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2119: {
2120:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2121:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2122:   PetscScalar       *vv;
2123:   Vec                vB, vA;
2124:   const PetscScalar *va, *vb;

2126:   PetscFunctionBegin;
2127:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2128:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2130:   PetscCall(VecGetArrayRead(vA, &va));
2131:   if (idx) {
2132:     for (i = 0; i < m; i++) {
2133:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2134:     }
2135:   }

2137:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2138:   PetscCall(PetscMalloc1(m, &idxb));
2139:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2141:   PetscCall(VecGetArrayWrite(v, &vv));
2142:   PetscCall(VecGetArrayRead(vB, &vb));
2143:   for (i = 0; i < m; i++) {
2144:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2145:       vv[i] = vb[i];
2146:       if (idx) idx[i] = a->garray[idxb[i]];
2147:     } else {
2148:       vv[i] = va[i];
2149:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2150:     }
2151:   }
2152:   PetscCall(VecRestoreArrayWrite(v, &vv));
2153:   PetscCall(VecRestoreArrayRead(vA, &va));
2154:   PetscCall(VecRestoreArrayRead(vB, &vb));
2155:   PetscCall(PetscFree(idxb));
2156:   PetscCall(VecDestroy(&vA));
2157:   PetscCall(VecDestroy(&vB));
2158:   PetscFunctionReturn(PETSC_SUCCESS);
2159: }

2161: static PetscErrorCode MatGetRowSumAbs_MPIAIJ(Mat A, Vec v)
2162: {
2163:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2164:   Vec         vB, vA;

2166:   PetscFunctionBegin;
2167:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2168:   PetscCall(MatGetRowSumAbs(a->A, vA));
2169:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2170:   PetscCall(MatGetRowSumAbs(a->B, vB));
2171:   PetscCall(VecAXPY(vA, 1.0, vB));
2172:   PetscCall(VecDestroy(&vB));
2173:   PetscCall(VecCopy(vA, v));
2174:   PetscCall(VecDestroy(&vA));
2175:   PetscFunctionReturn(PETSC_SUCCESS);
2176: }

2178: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2179: {
2180:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2181:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2182:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2183:   PetscInt          *cmap = mat->garray;
2184:   PetscInt          *diagIdx, *offdiagIdx;
2185:   Vec                diagV, offdiagV;
2186:   PetscScalar       *a, *diagA, *offdiagA;
2187:   const PetscScalar *ba, *bav;
2188:   PetscInt           r, j, col, ncols, *bi, *bj;
2189:   Mat                B = mat->B;
2190:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2192:   PetscFunctionBegin;
2193:   /* When a process holds entire A and other processes have no entry */
2194:   if (A->cmap->N == n) {
2195:     PetscCall(VecGetArrayWrite(v, &diagA));
2196:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2197:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2198:     PetscCall(VecDestroy(&diagV));
2199:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2200:     PetscFunctionReturn(PETSC_SUCCESS);
2201:   } else if (n == 0) {
2202:     if (m) {
2203:       PetscCall(VecGetArrayWrite(v, &a));
2204:       for (r = 0; r < m; r++) {
2205:         a[r] = 0.0;
2206:         if (idx) idx[r] = -1;
2207:       }
2208:       PetscCall(VecRestoreArrayWrite(v, &a));
2209:     }
2210:     PetscFunctionReturn(PETSC_SUCCESS);
2211:   }

2213:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2214:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2215:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2216:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2218:   /* Get offdiagIdx[] for implicit 0.0 */
2219:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2220:   ba = bav;
2221:   bi = b->i;
2222:   bj = b->j;
2223:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2224:   for (r = 0; r < m; r++) {
2225:     ncols = bi[r + 1] - bi[r];
2226:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2227:       offdiagA[r]   = *ba;
2228:       offdiagIdx[r] = cmap[0];
2229:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2230:       offdiagA[r] = 0.0;

2232:       /* Find first hole in the cmap */
2233:       for (j = 0; j < ncols; j++) {
2234:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2235:         if (col > j && j < cstart) {
2236:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2237:           break;
2238:         } else if (col > j + n && j >= cstart) {
2239:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2240:           break;
2241:         }
2242:       }
2243:       if (j == ncols && ncols < A->cmap->N - n) {
2244:         /* a hole is outside compressed Bcols */
2245:         if (ncols == 0) {
2246:           if (cstart) {
2247:             offdiagIdx[r] = 0;
2248:           } else offdiagIdx[r] = cend;
2249:         } else { /* ncols > 0 */
2250:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2251:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2252:         }
2253:       }
2254:     }

2256:     for (j = 0; j < ncols; j++) {
2257:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2258:         offdiagA[r]   = *ba;
2259:         offdiagIdx[r] = cmap[*bj];
2260:       }
2261:       ba++;
2262:       bj++;
2263:     }
2264:   }

2266:   PetscCall(VecGetArrayWrite(v, &a));
2267:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2268:   for (r = 0; r < m; ++r) {
2269:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2270:       a[r] = diagA[r];
2271:       if (idx) idx[r] = cstart + diagIdx[r];
2272:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2273:       a[r] = diagA[r];
2274:       if (idx) {
2275:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2276:           idx[r] = cstart + diagIdx[r];
2277:         } else idx[r] = offdiagIdx[r];
2278:       }
2279:     } else {
2280:       a[r] = offdiagA[r];
2281:       if (idx) idx[r] = offdiagIdx[r];
2282:     }
2283:   }
2284:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2285:   PetscCall(VecRestoreArrayWrite(v, &a));
2286:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2287:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2288:   PetscCall(VecDestroy(&diagV));
2289:   PetscCall(VecDestroy(&offdiagV));
2290:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2291:   PetscFunctionReturn(PETSC_SUCCESS);
2292: }

2294: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2295: {
2296:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2297:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2298:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2299:   PetscInt          *cmap = mat->garray;
2300:   PetscInt          *diagIdx, *offdiagIdx;
2301:   Vec                diagV, offdiagV;
2302:   PetscScalar       *a, *diagA, *offdiagA;
2303:   const PetscScalar *ba, *bav;
2304:   PetscInt           r, j, col, ncols, *bi, *bj;
2305:   Mat                B = mat->B;
2306:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2308:   PetscFunctionBegin;
2309:   /* When a process holds entire A and other processes have no entry */
2310:   if (A->cmap->N == n) {
2311:     PetscCall(VecGetArrayWrite(v, &diagA));
2312:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2313:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2314:     PetscCall(VecDestroy(&diagV));
2315:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2316:     PetscFunctionReturn(PETSC_SUCCESS);
2317:   } else if (n == 0) {
2318:     if (m) {
2319:       PetscCall(VecGetArrayWrite(v, &a));
2320:       for (r = 0; r < m; r++) {
2321:         a[r] = PETSC_MAX_REAL;
2322:         if (idx) idx[r] = -1;
2323:       }
2324:       PetscCall(VecRestoreArrayWrite(v, &a));
2325:     }
2326:     PetscFunctionReturn(PETSC_SUCCESS);
2327:   }

2329:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2330:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2331:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2332:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2334:   /* Get offdiagIdx[] for implicit 0.0 */
2335:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2336:   ba = bav;
2337:   bi = b->i;
2338:   bj = b->j;
2339:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2340:   for (r = 0; r < m; r++) {
2341:     ncols = bi[r + 1] - bi[r];
2342:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2343:       offdiagA[r]   = *ba;
2344:       offdiagIdx[r] = cmap[0];
2345:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2346:       offdiagA[r] = 0.0;

2348:       /* Find first hole in the cmap */
2349:       for (j = 0; j < ncols; j++) {
2350:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2351:         if (col > j && j < cstart) {
2352:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2353:           break;
2354:         } else if (col > j + n && j >= cstart) {
2355:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2356:           break;
2357:         }
2358:       }
2359:       if (j == ncols && ncols < A->cmap->N - n) {
2360:         /* a hole is outside compressed Bcols */
2361:         if (ncols == 0) {
2362:           if (cstart) {
2363:             offdiagIdx[r] = 0;
2364:           } else offdiagIdx[r] = cend;
2365:         } else { /* ncols > 0 */
2366:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2367:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2368:         }
2369:       }
2370:     }

2372:     for (j = 0; j < ncols; j++) {
2373:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2374:         offdiagA[r]   = *ba;
2375:         offdiagIdx[r] = cmap[*bj];
2376:       }
2377:       ba++;
2378:       bj++;
2379:     }
2380:   }

2382:   PetscCall(VecGetArrayWrite(v, &a));
2383:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2384:   for (r = 0; r < m; ++r) {
2385:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2386:       a[r] = diagA[r];
2387:       if (idx) idx[r] = cstart + diagIdx[r];
2388:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2389:       a[r] = diagA[r];
2390:       if (idx) {
2391:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2392:           idx[r] = cstart + diagIdx[r];
2393:         } else idx[r] = offdiagIdx[r];
2394:       }
2395:     } else {
2396:       a[r] = offdiagA[r];
2397:       if (idx) idx[r] = offdiagIdx[r];
2398:     }
2399:   }
2400:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2401:   PetscCall(VecRestoreArrayWrite(v, &a));
2402:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2403:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2404:   PetscCall(VecDestroy(&diagV));
2405:   PetscCall(VecDestroy(&offdiagV));
2406:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2407:   PetscFunctionReturn(PETSC_SUCCESS);
2408: }

2410: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2411: {
2412:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2413:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2414:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2415:   PetscInt          *cmap = mat->garray;
2416:   PetscInt          *diagIdx, *offdiagIdx;
2417:   Vec                diagV, offdiagV;
2418:   PetscScalar       *a, *diagA, *offdiagA;
2419:   const PetscScalar *ba, *bav;
2420:   PetscInt           r, j, col, ncols, *bi, *bj;
2421:   Mat                B = mat->B;
2422:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2424:   PetscFunctionBegin;
2425:   /* When a process holds entire A and other processes have no entry */
2426:   if (A->cmap->N == n) {
2427:     PetscCall(VecGetArrayWrite(v, &diagA));
2428:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2429:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2430:     PetscCall(VecDestroy(&diagV));
2431:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2432:     PetscFunctionReturn(PETSC_SUCCESS);
2433:   } else if (n == 0) {
2434:     if (m) {
2435:       PetscCall(VecGetArrayWrite(v, &a));
2436:       for (r = 0; r < m; r++) {
2437:         a[r] = PETSC_MIN_REAL;
2438:         if (idx) idx[r] = -1;
2439:       }
2440:       PetscCall(VecRestoreArrayWrite(v, &a));
2441:     }
2442:     PetscFunctionReturn(PETSC_SUCCESS);
2443:   }

2445:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2446:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2447:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2448:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2450:   /* Get offdiagIdx[] for implicit 0.0 */
2451:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2452:   ba = bav;
2453:   bi = b->i;
2454:   bj = b->j;
2455:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2456:   for (r = 0; r < m; r++) {
2457:     ncols = bi[r + 1] - bi[r];
2458:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2459:       offdiagA[r]   = *ba;
2460:       offdiagIdx[r] = cmap[0];
2461:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2462:       offdiagA[r] = 0.0;

2464:       /* Find first hole in the cmap */
2465:       for (j = 0; j < ncols; j++) {
2466:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2467:         if (col > j && j < cstart) {
2468:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2469:           break;
2470:         } else if (col > j + n && j >= cstart) {
2471:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2472:           break;
2473:         }
2474:       }
2475:       if (j == ncols && ncols < A->cmap->N - n) {
2476:         /* a hole is outside compressed Bcols */
2477:         if (ncols == 0) {
2478:           if (cstart) {
2479:             offdiagIdx[r] = 0;
2480:           } else offdiagIdx[r] = cend;
2481:         } else { /* ncols > 0 */
2482:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2483:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2484:         }
2485:       }
2486:     }

2488:     for (j = 0; j < ncols; j++) {
2489:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2490:         offdiagA[r]   = *ba;
2491:         offdiagIdx[r] = cmap[*bj];
2492:       }
2493:       ba++;
2494:       bj++;
2495:     }
2496:   }

2498:   PetscCall(VecGetArrayWrite(v, &a));
2499:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2500:   for (r = 0; r < m; ++r) {
2501:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2502:       a[r] = diagA[r];
2503:       if (idx) idx[r] = cstart + diagIdx[r];
2504:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2505:       a[r] = diagA[r];
2506:       if (idx) {
2507:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2508:           idx[r] = cstart + diagIdx[r];
2509:         } else idx[r] = offdiagIdx[r];
2510:       }
2511:     } else {
2512:       a[r] = offdiagA[r];
2513:       if (idx) idx[r] = offdiagIdx[r];
2514:     }
2515:   }
2516:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2517:   PetscCall(VecRestoreArrayWrite(v, &a));
2518:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2519:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2520:   PetscCall(VecDestroy(&diagV));
2521:   PetscCall(VecDestroy(&offdiagV));
2522:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2523:   PetscFunctionReturn(PETSC_SUCCESS);
2524: }

2526: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2527: {
2528:   Mat *dummy;

2530:   PetscFunctionBegin;
2531:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2532:   *newmat = *dummy;
2533:   PetscCall(PetscFree(dummy));
2534:   PetscFunctionReturn(PETSC_SUCCESS);
2535: }

2537: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2538: {
2539:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2541:   PetscFunctionBegin;
2542:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2543:   A->factorerrortype = a->A->factorerrortype;
2544:   PetscFunctionReturn(PETSC_SUCCESS);
2545: }

2547: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2548: {
2549:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2551:   PetscFunctionBegin;
2552:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2553:   PetscCall(MatSetRandom(aij->A, rctx));
2554:   if (x->assembled) {
2555:     PetscCall(MatSetRandom(aij->B, rctx));
2556:   } else {
2557:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2558:   }
2559:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2560:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2561:   PetscFunctionReturn(PETSC_SUCCESS);
2562: }

2564: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2565: {
2566:   PetscFunctionBegin;
2567:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2568:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2569:   PetscFunctionReturn(PETSC_SUCCESS);
2570: }

2572: /*@
2573:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2575:   Not Collective

2577:   Input Parameter:
2578: . A - the matrix

2580:   Output Parameter:
2581: . nz - the number of nonzeros

2583:   Level: advanced

2585: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2586: @*/
2587: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2588: {
2589:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2590:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2591:   PetscBool   isaij;

2593:   PetscFunctionBegin;
2594:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2595:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2596:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2597:   PetscFunctionReturn(PETSC_SUCCESS);
2598: }

2600: /*@
2601:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2603:   Collective

2605:   Input Parameters:
2606: + A  - the matrix
2607: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2609:   Level: advanced

2611: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2612: @*/
2613: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2614: {
2615:   PetscFunctionBegin;
2616:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2617:   PetscFunctionReturn(PETSC_SUCCESS);
2618: }

2620: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems PetscOptionsObject)
2621: {
2622:   PetscBool sc = PETSC_FALSE, flg;

2624:   PetscFunctionBegin;
2625:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2626:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2627:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2628:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2629:   PetscOptionsHeadEnd();
2630:   PetscFunctionReturn(PETSC_SUCCESS);
2631: }

2633: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2634: {
2635:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2636:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2638:   PetscFunctionBegin;
2639:   if (!Y->preallocated) {
2640:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2641:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2642:     PetscInt nonew = aij->nonew;
2643:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2644:     aij->nonew = nonew;
2645:   }
2646:   PetscCall(MatShift_Basic(Y, a));
2647:   PetscFunctionReturn(PETSC_SUCCESS);
2648: }

2650: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2651: {
2652:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2654:   PetscFunctionBegin;
2655:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2656:   PetscFunctionReturn(PETSC_SUCCESS);
2657: }

2659: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2660: {
2661:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2663:   PetscFunctionBegin;
2664:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2665:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2666:   PetscFunctionReturn(PETSC_SUCCESS);
2667: }

2669: static PetscErrorCode MatGetOrdering_MPIAIJ(Mat A, MatOrderingType type, IS *rperm, IS *cperm)
2670: {
2671:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
2672:   IS              lrowperm, lcolperm;
2673:   PetscInt        i, rstart, rend, *idx;
2674:   const PetscInt *lidx;

2676:   PetscFunctionBegin;
2677:   PetscCall(MatGetOrdering(a->A, type, &lrowperm, &lcolperm));
2678:   PetscCall(MatGetOwnershipRange(A, &rstart, &rend));
2679:   /* Remap row index set to global space */
2680:   PetscCall(ISGetIndices(lrowperm, &lidx));
2681:   PetscCall(PetscMalloc1(rend - rstart, &idx));
2682:   for (i = 0; i + rstart < rend; i++) idx[i] = rstart + lidx[i];
2683:   PetscCall(ISRestoreIndices(lrowperm, &lidx));
2684:   PetscCall(ISDestroy(&lrowperm));
2685:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), rend - rstart, idx, PETSC_OWN_POINTER, rperm));
2686:   PetscCall(ISSetPermutation(*rperm));
2687:   /* Remap column index set to global space */
2688:   PetscCall(ISGetIndices(lcolperm, &lidx));
2689:   PetscCall(PetscMalloc1(rend - rstart, &idx));
2690:   for (i = 0; i + rstart < rend; i++) idx[i] = rstart + lidx[i];
2691:   PetscCall(ISRestoreIndices(lcolperm, &lidx));
2692:   PetscCall(ISDestroy(&lcolperm));
2693:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), rend - rstart, idx, PETSC_OWN_POINTER, cperm));
2694:   PetscCall(ISSetPermutation(*cperm));
2695:   PetscFunctionReturn(PETSC_SUCCESS);
2696: }

2698: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2699:                                        MatGetRow_MPIAIJ,
2700:                                        MatRestoreRow_MPIAIJ,
2701:                                        MatMult_MPIAIJ,
2702:                                        /* 4*/ MatMultAdd_MPIAIJ,
2703:                                        MatMultTranspose_MPIAIJ,
2704:                                        MatMultTransposeAdd_MPIAIJ,
2705:                                        NULL,
2706:                                        NULL,
2707:                                        NULL,
2708:                                        /*10*/ NULL,
2709:                                        NULL,
2710:                                        NULL,
2711:                                        MatSOR_MPIAIJ,
2712:                                        MatTranspose_MPIAIJ,
2713:                                        /*15*/ MatGetInfo_MPIAIJ,
2714:                                        MatEqual_MPIAIJ,
2715:                                        MatGetDiagonal_MPIAIJ,
2716:                                        MatDiagonalScale_MPIAIJ,
2717:                                        MatNorm_MPIAIJ,
2718:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2719:                                        MatAssemblyEnd_MPIAIJ,
2720:                                        MatSetOption_MPIAIJ,
2721:                                        MatZeroEntries_MPIAIJ,
2722:                                        /*24*/ MatZeroRows_MPIAIJ,
2723:                                        NULL,
2724:                                        NULL,
2725:                                        NULL,
2726:                                        NULL,
2727:                                        /*29*/ MatSetUp_MPI_Hash,
2728:                                        NULL,
2729:                                        NULL,
2730:                                        MatGetDiagonalBlock_MPIAIJ,
2731:                                        NULL,
2732:                                        /*34*/ MatDuplicate_MPIAIJ,
2733:                                        NULL,
2734:                                        NULL,
2735:                                        NULL,
2736:                                        NULL,
2737:                                        /*39*/ MatAXPY_MPIAIJ,
2738:                                        MatCreateSubMatrices_MPIAIJ,
2739:                                        MatIncreaseOverlap_MPIAIJ,
2740:                                        MatGetValues_MPIAIJ,
2741:                                        MatCopy_MPIAIJ,
2742:                                        /*44*/ MatGetRowMax_MPIAIJ,
2743:                                        MatScale_MPIAIJ,
2744:                                        MatShift_MPIAIJ,
2745:                                        MatDiagonalSet_MPIAIJ,
2746:                                        MatZeroRowsColumns_MPIAIJ,
2747:                                        /*49*/ MatSetRandom_MPIAIJ,
2748:                                        MatGetRowIJ_MPIAIJ,
2749:                                        MatRestoreRowIJ_MPIAIJ,
2750:                                        NULL,
2751:                                        NULL,
2752:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2753:                                        NULL,
2754:                                        MatSetUnfactored_MPIAIJ,
2755:                                        MatPermute_MPIAIJ,
2756:                                        NULL,
2757:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2758:                                        MatDestroy_MPIAIJ,
2759:                                        MatView_MPIAIJ,
2760:                                        NULL,
2761:                                        NULL,
2762:                                        /*64*/ MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2763:                                        NULL,
2764:                                        NULL,
2765:                                        NULL,
2766:                                        MatGetRowMaxAbs_MPIAIJ,
2767:                                        /*69*/ MatGetRowMinAbs_MPIAIJ,
2768:                                        NULL,
2769:                                        NULL,
2770:                                        MatFDColoringApply_AIJ,
2771:                                        MatSetFromOptions_MPIAIJ,
2772:                                        MatFindZeroDiagonals_MPIAIJ,
2773:                                        /*75*/ NULL,
2774:                                        NULL,
2775:                                        NULL,
2776:                                        MatLoad_MPIAIJ,
2777:                                        NULL,
2778:                                        /*80*/ NULL,
2779:                                        NULL,
2780:                                        NULL,
2781:                                        /*83*/ NULL,
2782:                                        NULL,
2783:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2784:                                        MatPtAPNumeric_MPIAIJ_MPIAIJ,
2785:                                        NULL,
2786:                                        NULL,
2787:                                        /*89*/ MatBindToCPU_MPIAIJ,
2788:                                        MatProductSetFromOptions_MPIAIJ,
2789:                                        NULL,
2790:                                        NULL,
2791:                                        MatConjugate_MPIAIJ,
2792:                                        /*94*/ NULL,
2793:                                        MatSetValuesRow_MPIAIJ,
2794:                                        MatRealPart_MPIAIJ,
2795:                                        MatImaginaryPart_MPIAIJ,
2796:                                        NULL,
2797:                                        /*99*/ NULL,
2798:                                        NULL,
2799:                                        NULL,
2800:                                        MatGetRowMin_MPIAIJ,
2801:                                        NULL,
2802:                                        /*104*/ MatGetSeqNonzeroStructure_MPIAIJ,
2803:                                        NULL,
2804:                                        MatGetGhosts_MPIAIJ,
2805:                                        NULL,
2806:                                        NULL,
2807:                                        /*109*/ MatMultDiagonalBlock_MPIAIJ,
2808:                                        NULL,
2809:                                        NULL,
2810:                                        NULL,
2811:                                        MatGetMultiProcBlock_MPIAIJ,
2812:                                        /*114*/ MatFindNonzeroRows_MPIAIJ,
2813:                                        MatGetColumnReductions_MPIAIJ,
2814:                                        MatInvertBlockDiagonal_MPIAIJ,
2815:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2816:                                        MatCreateSubMatricesMPI_MPIAIJ,
2817:                                        /*119*/ NULL,
2818:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2819:                                        NULL,
2820:                                        NULL,
2821:                                        NULL,
2822:                                        /*124*/ NULL,
2823:                                        MatSetBlockSizes_MPIAIJ,
2824:                                        NULL,
2825:                                        MatFDColoringSetUp_MPIXAIJ,
2826:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2827:                                        /*129*/ MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2828:                                        NULL,
2829:                                        NULL,
2830:                                        NULL,
2831:                                        MatCreateGraph_Simple_AIJ,
2832:                                        /*134*/ NULL,
2833:                                        MatEliminateZeros_MPIAIJ,
2834:                                        MatGetRowSumAbs_MPIAIJ,
2835:                                        NULL,
2836:                                        NULL,
2837:                                        /*139*/ NULL,
2838:                                        MatCopyHashToXAIJ_MPI_Hash,
2839:                                        MatGetCurrentMemType_MPIAIJ,
2840:                                        NULL,
2841:                                        NULL,
2842:                                        /*144*/ NULL,
2843:                                        NULL,
2844:                                        NULL,
2845:                                        MatGetOrdering_MPIAIJ};

2847: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2848: {
2849:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2851:   PetscFunctionBegin;
2852:   PetscCall(MatStoreValues(aij->A));
2853:   PetscCall(MatStoreValues(aij->B));
2854:   PetscFunctionReturn(PETSC_SUCCESS);
2855: }

2857: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2858: {
2859:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2861:   PetscFunctionBegin;
2862:   PetscCall(MatRetrieveValues(aij->A));
2863:   PetscCall(MatRetrieveValues(aij->B));
2864:   PetscFunctionReturn(PETSC_SUCCESS);
2865: }

2867: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2868: {
2869:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2870:   PetscMPIInt size;

2872:   PetscFunctionBegin;
2873:   if (B->hash_active) {
2874:     B->ops[0]      = b->cops;
2875:     B->hash_active = PETSC_FALSE;
2876:   }
2877:   PetscCall(PetscLayoutSetUp(B->rmap));
2878:   PetscCall(PetscLayoutSetUp(B->cmap));

2880: #if PetscDefined(USE_CTABLE)
2881:   PetscCall(PetscHMapIDestroy(&b->colmap));
2882: #else
2883:   PetscCall(PetscFree(b->colmap));
2884: #endif
2885:   PetscCall(PetscFree(b->garray));
2886:   PetscCall(VecDestroy(&b->lvec));
2887:   PetscCall(VecScatterDestroy(&b->Mvctx));

2889:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2891:   MatSeqXAIJGetOptions_Private(b->B);
2892:   PetscCall(MatDestroy(&b->B));
2893:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2894:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2895:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2896:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2897:   MatSeqXAIJRestoreOptions_Private(b->B);
2898:   PetscCall(MatSetOption(b->B, MAT_STRUCTURE_ONLY, B->structure_only));

2900:   MatSeqXAIJGetOptions_Private(b->A);
2901:   PetscCall(MatDestroy(&b->A));
2902:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2903:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2904:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2905:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2906:   MatSeqXAIJRestoreOptions_Private(b->A);
2907:   PetscCall(MatSetOption(b->A, MAT_STRUCTURE_ONLY, B->structure_only));

2909:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2910:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2911:   B->preallocated  = PETSC_TRUE;
2912:   B->was_assembled = PETSC_FALSE;
2913:   B->assembled     = PETSC_FALSE;
2914:   PetscFunctionReturn(PETSC_SUCCESS);
2915: }

2917: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2918: {
2919:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2920:   PetscBool   ondiagreset, offdiagreset, memoryreset;

2922:   PetscFunctionBegin;
2924:   PetscCheck(B->insertmode == NOT_SET_VALUES, PETSC_COMM_SELF, PETSC_ERR_SUP, "Cannot reset preallocation after setting some values but not yet calling MatAssemblyBegin()/MatAssemblyEnd()");
2925:   if (B->num_ass == 0) PetscFunctionReturn(PETSC_SUCCESS);

2927:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->A, &ondiagreset));
2928:   PetscCall(MatResetPreallocation_SeqAIJ_Private(b->B, &offdiagreset));
2929:   memoryreset = (PetscBool)(ondiagreset || offdiagreset);
2930:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &memoryreset, 1, MPI_C_BOOL, MPI_LOR, PetscObjectComm((PetscObject)B)));
2931:   if (!memoryreset) PetscFunctionReturn(PETSC_SUCCESS);

2933:   PetscCall(PetscLayoutSetUp(B->rmap));
2934:   PetscCall(PetscLayoutSetUp(B->cmap));
2935:   PetscCheck(B->assembled || B->was_assembled, PetscObjectComm((PetscObject)B), PETSC_ERR_ARG_WRONGSTATE, "Should not need to reset preallocation if the matrix was never assembled");
2936:   PetscCall(MatDisAssemble_MPIAIJ(B, PETSC_TRUE));
2937:   PetscCall(VecScatterDestroy(&b->Mvctx));

2939:   B->preallocated  = PETSC_TRUE;
2940:   B->was_assembled = PETSC_FALSE;
2941:   B->assembled     = PETSC_FALSE;
2942:   /* Log that the state of this object has changed; this will help guarantee that preconditioners get re-setup */
2943:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2944:   PetscFunctionReturn(PETSC_SUCCESS);
2945: }

2947: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2948: {
2949:   Mat         mat;
2950:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2952:   PetscFunctionBegin;
2953:   *newmat = NULL;
2954:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2955:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2956:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2957:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2958:   PetscCall(MatSetOption(mat, MAT_STRUCTURE_ONLY, matin->structure_only));
2959:   a = (Mat_MPIAIJ *)mat->data;

2961:   mat->factortype = matin->factortype;
2962:   mat->assembled  = matin->assembled;
2963:   mat->insertmode = NOT_SET_VALUES;

2965:   a->size         = oldmat->size;
2966:   a->rank         = oldmat->rank;
2967:   a->donotstash   = oldmat->donotstash;
2968:   a->roworiented  = oldmat->roworiented;
2969:   a->rowindices   = NULL;
2970:   a->rowvalues    = NULL;
2971:   a->getrowactive = PETSC_FALSE;

2973:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
2974:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
2975:   if (matin->hash_active) PetscCall(MatSetUp(mat));
2976:   else {
2977:     mat->preallocated = matin->preallocated;
2978:     if (oldmat->colmap) {
2979: #if PetscDefined(USE_CTABLE)
2980:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
2981: #else
2982:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
2983:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
2984: #endif
2985:     } else a->colmap = NULL;
2986:     if (oldmat->garray) {
2987:       PetscInt len;
2988:       len = oldmat->B->cmap->n;
2989:       PetscCall(PetscMalloc1(len, &a->garray));
2990:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
2991:     } else a->garray = NULL;

2993:     /* It may happen MatDuplicate is called with a non-assembled matrix
2994:       In fact, MatDuplicate only requires the matrix to be preallocated
2995:       This may happen inside a DMCreateMatrix_Shell */
2996:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
2997:     if (oldmat->Mvctx) {
2998:       a->Mvctx = oldmat->Mvctx;
2999:       PetscCall(PetscObjectReference((PetscObject)oldmat->Mvctx));
3000:     }
3001:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3002:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3003:   }
3004:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3005:   *newmat = mat;
3006:   PetscFunctionReturn(PETSC_SUCCESS);
3007: }

3009: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3010: {
3011:   PetscBool isbinary, ishdf5;

3013:   PetscFunctionBegin;
3016:   /* force binary viewer to load .info file if it has not yet done so */
3017:   PetscCall(PetscViewerSetUp(viewer));
3018:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3019:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3020:   if (isbinary) {
3021:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3022:   } else if (ishdf5) {
3023: #if PetscDefined(HAVE_HDF5)
3024:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3025: #else
3026:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3027: #endif
3028:   } else {
3029:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "Viewer type %s not yet supported for reading %s matrices", ((PetscObject)viewer)->type_name, ((PetscObject)newMat)->type_name);
3030:   }
3031:   PetscFunctionReturn(PETSC_SUCCESS);
3032: }

3034: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3035: {
3036:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3037:   PetscInt    *rowidxs, *colidxs;
3038:   PetscScalar *matvals;

3040:   PetscFunctionBegin;
3041:   PetscCall(PetscViewerSetUp(viewer));

3043:   /* read in matrix header */
3044:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3045:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3046:   M  = header[1];
3047:   N  = header[2];
3048:   nz = header[3];
3049:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3050:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3051:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3053:   /* set block sizes from the viewer's .info file */
3054:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3055:   /* set global sizes if not set already */
3056:   if (mat->rmap->N < 0) mat->rmap->N = M;
3057:   if (mat->cmap->N < 0) mat->cmap->N = N;
3058:   PetscCall(PetscLayoutSetUp(mat->rmap));
3059:   PetscCall(PetscLayoutSetUp(mat->cmap));

3061:   /* check if the matrix sizes are correct */
3062:   PetscCall(MatGetSize(mat, &rows, &cols));
3063:   PetscCheck(M == rows && N == cols, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix in file of different sizes (%" PetscInt_FMT ", %" PetscInt_FMT ") than the input matrix (%" PetscInt_FMT ", %" PetscInt_FMT ")", M, N, rows, cols);

3065:   /* read in row lengths and build row indices */
3066:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3067:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3068:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3069:   rowidxs[0] = 0;
3070:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3071:   if (nz != PETSC_INT_MAX) {
3072:     PetscCallMPI(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3073:     PetscCheck(sum == nz, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Inconsistent matrix data in file: nonzeros = %" PetscInt_FMT ", sum-row-lengths = %" PetscInt_FMT, nz, sum);
3074:   }

3076:   /* read in column indices and matrix values */
3077:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3078:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3079:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3080:   /* store matrix indices and values */
3081:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3082:   PetscCall(PetscFree(rowidxs));
3083:   PetscCall(PetscFree2(colidxs, matvals));
3084:   PetscFunctionReturn(PETSC_SUCCESS);
3085: }

3087: /* Not scalable because of ISAllGather() unless getting all columns. */
3088: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3089: {
3090:   IS          iscol_local;
3091:   PetscBool   isstride;
3092:   PetscMPIInt gisstride = 0;

3094:   PetscFunctionBegin;
3095:   /* check if we are grabbing all columns*/
3096:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3098:   if (isstride) {
3099:     PetscInt start, len, mstart, mlen;
3100:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3101:     PetscCall(ISGetLocalSize(iscol, &len));
3102:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3103:     if (mstart == start && mlen - mstart == len) gisstride = 1;
3104:   }

3106:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3107:   if (gisstride) {
3108:     PetscInt N;
3109:     PetscCall(MatGetSize(mat, NULL, &N));
3110:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3111:     PetscCall(ISSetIdentity(iscol_local));
3112:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3113:   } else {
3114:     PetscInt cbs;
3115:     PetscCall(ISGetBlockSize(iscol, &cbs));
3116:     PetscCall(ISAllGather(iscol, &iscol_local));
3117:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3118:   }

3120:   *isseq = iscol_local;
3121:   PetscFunctionReturn(PETSC_SUCCESS);
3122: }

3124: /*
3125:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3126:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3128:  Input Parameters:
3129: +   mat - matrix
3130: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3131:            i.e., mat->rstart <= isrow[i] < mat->rend
3132: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3133:            i.e., mat->cstart <= iscol[i] < mat->cend

3135:  Output Parameters:
3136: +   isrow_d - sequential row index set for retrieving mat->A
3137: .   iscol_d - sequential  column index set for retrieving mat->A
3138: .   iscol_o - sequential column index set for retrieving mat->B
3139: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3140:  */
3141: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, PetscInt *garray[])
3142: {
3143:   Vec             x, cmap;
3144:   const PetscInt *is_idx;
3145:   PetscScalar    *xarray, *cmaparray;
3146:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3147:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3148:   Mat             B    = a->B;
3149:   Vec             lvec = a->lvec, lcmap;
3150:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3151:   MPI_Comm        comm;
3152:   VecScatter      Mvctx = a->Mvctx;

3154:   PetscFunctionBegin;
3155:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3156:   PetscCall(ISGetLocalSize(iscol, &ncols));

3158:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3159:   PetscCall(MatCreateVecs(mat, &x, NULL));
3160:   PetscCall(VecSet(x, -1.0));
3161:   PetscCall(VecDuplicate(x, &cmap));
3162:   PetscCall(VecSet(cmap, -1.0));

3164:   /* Get start indices */
3165:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3166:   isstart -= ncols;
3167:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3169:   PetscCall(ISGetIndices(iscol, &is_idx));
3170:   PetscCall(VecGetArray(x, &xarray));
3171:   PetscCall(VecGetArray(cmap, &cmaparray));
3172:   PetscCall(PetscMalloc1(ncols, &idx));
3173:   for (i = 0; i < ncols; i++) {
3174:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3175:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3176:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3177:   }
3178:   PetscCall(VecRestoreArray(x, &xarray));
3179:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3180:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3182:   /* Get iscol_d */
3183:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3184:   PetscCall(ISGetBlockSize(iscol, &i));
3185:   PetscCall(ISSetBlockSize(*iscol_d, i));

3187:   /* Get isrow_d */
3188:   PetscCall(ISGetLocalSize(isrow, &m));
3189:   rstart = mat->rmap->rstart;
3190:   PetscCall(PetscMalloc1(m, &idx));
3191:   PetscCall(ISGetIndices(isrow, &is_idx));
3192:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3193:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3195:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3196:   PetscCall(ISGetBlockSize(isrow, &i));
3197:   PetscCall(ISSetBlockSize(*isrow_d, i));

3199:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3200:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3201:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3203:   PetscCall(VecDuplicate(lvec, &lcmap));

3205:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3206:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3208:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3209:   /* off-process column indices */
3210:   count = 0;
3211:   PetscCall(PetscMalloc1(Bn, &idx));
3212:   PetscCall(PetscMalloc1(Bn, &cmap1));

3214:   PetscCall(VecGetArray(lvec, &xarray));
3215:   PetscCall(VecGetArray(lcmap, &cmaparray));
3216:   for (i = 0; i < Bn; i++) {
3217:     if (PetscRealPart(xarray[i]) > -1.0) {
3218:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3219:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3220:       count++;
3221:     }
3222:   }
3223:   PetscCall(VecRestoreArray(lvec, &xarray));
3224:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3226:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3227:   /* cannot ensure iscol_o has same blocksize as iscol! */

3229:   PetscCall(PetscFree(idx));
3230:   *garray = cmap1;

3232:   PetscCall(VecDestroy(&x));
3233:   PetscCall(VecDestroy(&cmap));
3234:   PetscCall(VecDestroy(&lcmap));
3235:   PetscFunctionReturn(PETSC_SUCCESS);
3236: }

3238: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3239: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3240: {
3241:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3242:   Mat         M = NULL;
3243:   MPI_Comm    comm;
3244:   IS          iscol_d, isrow_d, iscol_o;
3245:   Mat         Asub = NULL, Bsub = NULL;
3246:   PetscInt    n, count, M_size, N_size;

3248:   PetscFunctionBegin;
3249:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3251:   if (call == MAT_REUSE_MATRIX) {
3252:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3253:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3254:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3256:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3257:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3259:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3260:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3262:     /* Update diagonal and off-diagonal portions of submat */
3263:     asub = (Mat_MPIAIJ *)(*submat)->data;
3264:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3265:     PetscCall(ISGetLocalSize(iscol_o, &n));
3266:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3267:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3268:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3270:   } else { /* call == MAT_INITIAL_MATRIX) */
3271:     PetscInt *garray, *garray_compact;
3272:     PetscInt  BsubN;

3274:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3275:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3277:     /* Create local submatrices Asub and Bsub */
3278:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3279:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3281:     // Compact garray so its not of size Bn
3282:     PetscCall(ISGetSize(iscol_o, &count));
3283:     PetscCall(PetscMalloc1(count, &garray_compact));
3284:     PetscCall(PetscArraycpy(garray_compact, garray, count));

3286:     /* Create submatrix M */
3287:     PetscCall(ISGetSize(isrow, &M_size));
3288:     PetscCall(ISGetSize(iscol, &N_size));
3289:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, M_size, N_size, Asub, Bsub, garray_compact, &M));

3291:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3292:     asub = (Mat_MPIAIJ *)M->data;

3294:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3295:     n = asub->B->cmap->N;
3296:     if (BsubN > n) {
3297:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3298:       const PetscInt *idx;
3299:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3300:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3302:       PetscCall(PetscMalloc1(n, &idx_new));
3303:       j = 0;
3304:       PetscCall(ISGetIndices(iscol_o, &idx));
3305:       for (i = 0; i < n; i++) {
3306:         if (j >= BsubN) break;
3307:         while (subgarray[i] > garray[j]) j++;

3309:         PetscCheck(subgarray[i] == garray[j], PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "subgarray[%" PetscInt_FMT "]=%" PetscInt_FMT " cannot < garray[%" PetscInt_FMT "]=%" PetscInt_FMT, i, subgarray[i], j, garray[j]);
3310:         idx_new[i] = idx[j++];
3311:       }
3312:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3314:       PetscCall(ISDestroy(&iscol_o));
3315:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3317:     } else PetscCheck(BsubN >= n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Columns of Bsub (%" PetscInt_FMT ") cannot be smaller than B's (%" PetscInt_FMT ")", BsubN, asub->B->cmap->N);

3319:     PetscCall(PetscFree(garray));
3320:     *submat = M;

3322:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3323:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3324:     PetscCall(ISDestroy(&isrow_d));

3326:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3327:     PetscCall(ISDestroy(&iscol_d));

3329:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3330:     PetscCall(ISDestroy(&iscol_o));
3331:   }
3332:   PetscFunctionReturn(PETSC_SUCCESS);
3333: }

3335: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3336: {
3337:   IS        iscol_local = NULL, isrow_d;
3338:   PetscInt  csize;
3339:   PetscInt  n, i, j, start, end;
3340:   PetscBool sameRowDist = PETSC_FALSE, tsameDist[2];
3341:   MPI_Comm  comm;

3343:   PetscFunctionBegin;
3344:   /* If isrow has same processor distribution as mat,
3345:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3346:   if (call == MAT_REUSE_MATRIX) {
3347:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3348:     if (isrow_d) {
3349:       sameRowDist  = PETSC_TRUE;
3350:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3351:     } else {
3352:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3353:       if (iscol_local) {
3354:         sameRowDist  = PETSC_TRUE;
3355:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3356:       }
3357:     }
3358:   } else {
3359:     /* Check if isrow has same processor distribution as mat */
3360:     tsameDist[0] = PETSC_FALSE;
3361:     PetscCall(ISGetLocalSize(isrow, &n));
3362:     if (!n) {
3363:       tsameDist[0] = PETSC_TRUE;
3364:     } else {
3365:       PetscCall(ISGetMinMax(isrow, &i, &j));
3366:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3367:       if (i >= start && j < end) tsameDist[0] = PETSC_TRUE;
3368:     }

3370:     /* Check if iscol has same processor distribution as mat */
3371:     tsameDist[1] = PETSC_FALSE;
3372:     PetscCall(ISGetLocalSize(iscol, &n));
3373:     if (!n) {
3374:       tsameDist[1] = PETSC_TRUE;
3375:     } else {
3376:       PetscCall(ISGetMinMax(iscol, &i, &j));
3377:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3378:       if (i >= start && j < end) tsameDist[1] = PETSC_TRUE;
3379:     }

3381:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3382:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, tsameDist, 2, MPI_C_BOOL, MPI_LAND, comm));
3383:     sameRowDist = tsameDist[0];
3384:   }

3386:   if (sameRowDist) {
3387:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3388:       /* isrow and iscol have same processor distribution as mat */
3389:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3390:       PetscFunctionReturn(PETSC_SUCCESS);
3391:     } else { /* sameRowDist */
3392:       /* isrow has same processor distribution as mat */
3393:       if (call == MAT_INITIAL_MATRIX) {
3394:         PetscBool sorted;
3395:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3396:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3397:         PetscCall(ISGetSize(iscol, &i));
3398:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3400:         PetscCall(ISSorted(iscol_local, &sorted));
3401:         if (sorted) {
3402:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3403:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3404:           PetscFunctionReturn(PETSC_SUCCESS);
3405:         }
3406:       } else { /* call == MAT_REUSE_MATRIX */
3407:         IS iscol_sub;
3408:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3409:         if (iscol_sub) {
3410:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3411:           PetscFunctionReturn(PETSC_SUCCESS);
3412:         }
3413:       }
3414:     }
3415:   }

3417:   /* General case: iscol -> iscol_local which has global size of iscol */
3418:   if (call == MAT_REUSE_MATRIX) {
3419:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3420:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3421:   } else {
3422:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3423:   }

3425:   PetscCall(ISGetLocalSize(iscol, &csize));
3426:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3428:   if (call == MAT_INITIAL_MATRIX) {
3429:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3430:     PetscCall(ISDestroy(&iscol_local));
3431:   }
3432:   PetscFunctionReturn(PETSC_SUCCESS);
3433: }

3435: /*@
3436:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3437:   and "off-diagonal" part of the matrix in CSR format.

3439:   Collective

3441:   Input Parameters:
3442: + comm   - MPI communicator
3443: . M      - the global row size
3444: . N      - the global column size
3445: . A      - "diagonal" portion of matrix
3446: . B      - if garray is `NULL`, B should be the offdiag matrix using global col ids and of size N - if garray is not `NULL`, B should be the offdiag matrix using local col ids and of size garray
3447: - garray - either `NULL` or the global index of `B` columns. If not `NULL`, it should be allocated by `PetscMalloc1()` and will be owned by `mat` thereafter.

3449:   Output Parameter:
3450: . mat - the matrix, with input `A` as its local diagonal matrix

3452:   Level: advanced

3454:   Notes:
3455:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3457:   `A` and `B` becomes part of output mat. The user cannot use `A` and `B` anymore.

3459:   If `garray` is `NULL`, `B` will be compacted to use local indices. In this sense, `B`'s sparsity pattern (nonzerostate) will be changed. If `B` is a device matrix, we need to somehow also update
3460:   `B`'s copy on device.  We do so by increasing `B`'s nonzerostate. In use of `B` on device, device matrix types should detect this change (ref. internal routines `MatSeqAIJCUSPARSECopyToGPU()` or
3461:   `MatAssemblyEnd_SeqAIJKokkos()`) and will just destroy and then recreate the device copy of `B`. It is not optimal, but is easy to implement and less hacky. To avoid this overhead, try to compute `garray`
3462:   yourself, see algorithms in the private function `MatSetUpMultiply_MPIAIJ()`.

3464:   The `NULL`-ness of `garray` doesn't need to be collective, in other words, `garray` can be `NULL` on some processes while not on others.

3466: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3467: @*/
3468: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, PetscInt M, PetscInt N, Mat A, Mat B, PetscInt *garray, Mat *mat)
3469: {
3470:   PetscInt    m, n;
3471:   MatType     mpi_mat_type;
3472:   Mat_MPIAIJ *mpiaij;
3473:   Mat         C;

3475:   PetscFunctionBegin;
3476:   PetscCall(MatCreate(comm, &C));
3477:   PetscCall(MatGetSize(A, &m, &n));
3478:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3479:   PetscCheck(A->rmap->bs == B->rmap->bs, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "A row bs %" PetscInt_FMT " != B row bs %" PetscInt_FMT, A->rmap->bs, B->rmap->bs);

3481:   PetscCheck(A->structure_only == B->structure_only, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Diagonal and off-diagonal matrices must have the same MAT_STRUCTURE_ONLY option value");
3482:   PetscCall(MatSetSizes(C, m, n, M, N));
3483:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3484:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3485:   PetscCall(MatSetType(C, mpi_mat_type));
3486:   if (!garray) {
3487:     const PetscScalar *ba;

3489:     B->nonzerostate++;
3490:     PetscCall(MatSeqAIJGetArrayRead(B, &ba)); /* Since we will destroy B's device copy, we need to make sure the host copy is up to date */
3491:     PetscCall(MatSeqAIJRestoreArrayRead(B, &ba));
3492:   }

3494:   PetscCall(MatSetBlockSizes(C, A->rmap->bs, A->cmap->bs));
3495:   PetscCall(PetscLayoutSetUp(C->rmap));
3496:   PetscCall(PetscLayoutSetUp(C->cmap));

3498:   mpiaij              = (Mat_MPIAIJ *)C->data;
3499:   mpiaij->A           = A;
3500:   mpiaij->B           = B;
3501:   mpiaij->garray      = garray;
3502:   C->preallocated     = PETSC_TRUE;
3503:   C->nooffprocentries = PETSC_TRUE; /* See MatAssemblyBegin_MPIAIJ. In effect, making MatAssemblyBegin a nop */

3505:   PetscCall(MatSetOption(C, MAT_STRUCTURE_ONLY, A->structure_only));
3506:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3507:   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
3508:   /* MatAssemblyEnd is critical here. It sets mat->offloadmask according to A and B's, and
3509:    also gets mpiaij->B compacted (if garray is NULL), with its col ids and size reduced
3510:    */
3511:   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
3512:   PetscCall(MatSetOption(C, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3513:   PetscCall(MatSetOption(C, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3514:   *mat = C;
3515:   PetscFunctionReturn(PETSC_SUCCESS);
3516: }

3518: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3520: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3521: {
3522:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3523:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3524:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3525:   Mat             M, Msub, B = a->B;
3526:   MatScalar      *aa;
3527:   Mat_SeqAIJ     *aij;
3528:   PetscInt       *garray = a->garray, *colsub, Ncols;
3529:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3530:   IS              iscol_sub, iscmap;
3531:   const PetscInt *is_idx, *cmap;
3532:   PetscBool       allcolumns = PETSC_FALSE;
3533:   MPI_Comm        comm;

3535:   PetscFunctionBegin;
3536:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3537:   if (call == MAT_REUSE_MATRIX) {
3538:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3539:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3540:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3542:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3543:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3545:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3546:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3548:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3550:   } else { /* call == MAT_INITIAL_MATRIX) */
3551:     PetscBool flg;

3553:     PetscCall(ISGetLocalSize(iscol, &n));
3554:     PetscCall(ISGetSize(iscol, &Ncols));

3556:     /* (1) iscol -> nonscalable iscol_local */
3557:     /* Check for special case: each processor gets entire matrix columns */
3558:     PetscCall(ISIdentity(iscol_local, &flg));
3559:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3560:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3561:     if (allcolumns) {
3562:       iscol_sub = iscol_local;
3563:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3564:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3566:     } else {
3567:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3568:       PetscInt *idx, *cmap1, k;
3569:       PetscCall(PetscMalloc1(Ncols, &idx));
3570:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3571:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3572:       count = 0;
3573:       k     = 0;
3574:       for (i = 0; i < Ncols; i++) {
3575:         j = is_idx[i];
3576:         if (j >= cstart && j < cend) {
3577:           /* diagonal part of mat */
3578:           idx[count]     = j;
3579:           cmap1[count++] = i; /* column index in submat */
3580:         } else if (Bn) {
3581:           /* off-diagonal part of mat */
3582:           if (j == garray[k]) {
3583:             idx[count]     = j;
3584:             cmap1[count++] = i; /* column index in submat */
3585:           } else if (j > garray[k]) {
3586:             while (j > garray[k] && k < Bn - 1) k++;
3587:             if (j == garray[k]) {
3588:               idx[count]     = j;
3589:               cmap1[count++] = i; /* column index in submat */
3590:             }
3591:           }
3592:         }
3593:       }
3594:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3596:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3597:       PetscCall(ISGetBlockSize(iscol, &cbs));
3598:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3600:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3601:     }

3603:     /* (3) Create sequential Msub */
3604:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3605:   }

3607:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3608:   aij = (Mat_SeqAIJ *)Msub->data;
3609:   ii  = aij->i;
3610:   PetscCall(ISGetIndices(iscmap, &cmap));

3612:   /*
3613:       m - number of local rows
3614:       Ncols - number of columns (same on all processors)
3615:       rstart - first row in new global matrix generated
3616:   */
3617:   PetscCall(MatGetSize(Msub, &m, NULL));

3619:   if (call == MAT_INITIAL_MATRIX) {
3620:     /* (4) Create parallel newmat */
3621:     PetscMPIInt rank, size;
3622:     PetscInt    csize;

3624:     PetscCallMPI(MPI_Comm_size(comm, &size));
3625:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3627:     /*
3628:         Determine the number of non-zeros in the diagonal and off-diagonal
3629:         portions of the matrix in order to do correct preallocation
3630:     */

3632:     /* first get start and end of "diagonal" columns */
3633:     PetscCall(ISGetLocalSize(iscol, &csize));
3634:     if (csize == PETSC_DECIDE) {
3635:       PetscCall(ISGetSize(isrow, &mglobal));
3636:       if (mglobal == Ncols) { /* square matrix */
3637:         nlocal = m;
3638:       } else {
3639:         nlocal = Ncols / size + ((Ncols % size) > rank);
3640:       }
3641:     } else {
3642:       nlocal = csize;
3643:     }
3644:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3645:     rstart = rend - nlocal;
3646:     PetscCheck(rank != size - 1 || rend == Ncols, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Local column sizes %" PetscInt_FMT " do not add up to total number of columns %" PetscInt_FMT, rend, Ncols);

3648:     /* next, compute all the lengths */
3649:     jj = aij->j;
3650:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3651:     olens = dlens + m;
3652:     for (i = 0; i < m; i++) {
3653:       jend = ii[i + 1] - ii[i];
3654:       olen = 0;
3655:       dlen = 0;
3656:       for (j = 0; j < jend; j++) {
3657:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3658:         else dlen++;
3659:         jj++;
3660:       }
3661:       olens[i] = olen;
3662:       dlens[i] = dlen;
3663:     }

3665:     PetscCall(ISGetBlockSize(isrow, &bs));
3666:     PetscCall(ISGetBlockSize(iscol, &cbs));

3668:     PetscCall(MatCreate(comm, &M));
3669:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3670:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3671:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3672:     PetscCall(MatSetOption(M, MAT_STRUCTURE_ONLY, mat->structure_only));
3673:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3674:     PetscCall(PetscFree(dlens));

3676:   } else { /* call == MAT_REUSE_MATRIX */
3677:     M = *newmat;
3678:     PetscCall(MatGetLocalSize(M, &i, NULL));
3679:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3680:     PetscCall(MatZeroEntries(M));
3681:     /*
3682:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3683:        rather than the slower MatSetValues().
3684:     */
3685:     M->was_assembled = PETSC_TRUE;
3686:     M->assembled     = PETSC_FALSE;
3687:   }

3689:   /* (5) Set values of Msub to *newmat */
3690:   PetscCall(PetscMalloc1(count, &colsub));
3691:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3693:   jj = aij->j;
3694:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3695:   for (i = 0; i < m; i++) {
3696:     row = rstart + i;
3697:     nz  = ii[i + 1] - ii[i];
3698:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3699:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3700:     jj += nz;
3701:     if (!mat->structure_only) aa += nz;
3702:   }
3703:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3704:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3706:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3707:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3709:   PetscCall(PetscFree(colsub));

3711:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3712:   if (call == MAT_INITIAL_MATRIX) {
3713:     *newmat = M;
3714:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3715:     PetscCall(MatDestroy(&Msub));

3717:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3718:     PetscCall(ISDestroy(&iscol_sub));

3720:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3721:     PetscCall(ISDestroy(&iscmap));

3723:     if (iscol_local) {
3724:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3725:       PetscCall(ISDestroy(&iscol_local));
3726:     }
3727:   }
3728:   PetscFunctionReturn(PETSC_SUCCESS);
3729: }

3731: /*
3732:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3733:   in local and then by concatenating the local matrices the end result.
3734:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3736:   This requires a sequential iscol with all indices.
3737: */
3738: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3739: {
3740:   PetscMPIInt rank, size;
3741:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3742:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3743:   Mat         M, Mreuse;
3744:   MatScalar  *aa, *vwork;
3745:   MPI_Comm    comm;
3746:   Mat_SeqAIJ *aij;
3747:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3749:   PetscFunctionBegin;
3750:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3751:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3752:   PetscCallMPI(MPI_Comm_size(comm, &size));

3754:   /* Check for special case: each processor gets entire matrix columns */
3755:   PetscCall(ISIdentity(iscol, &colflag));
3756:   PetscCall(ISGetLocalSize(iscol, &n));
3757:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3758:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPI_C_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3760:   if (call == MAT_REUSE_MATRIX) {
3761:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3762:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3763:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3764:   } else {
3765:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3766:   }

3768:   /*
3769:       m - number of local rows
3770:       n - number of columns (same on all processors)
3771:       rstart - first row in new global matrix generated
3772:   */
3773:   PetscCall(MatGetSize(Mreuse, &m, &n));
3774:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3775:   if (call == MAT_INITIAL_MATRIX) {
3776:     aij = (Mat_SeqAIJ *)Mreuse->data;
3777:     ii  = aij->i;
3778:     jj  = aij->j;

3780:     /*
3781:         Determine the number of non-zeros in the diagonal and off-diagonal
3782:         portions of the matrix in order to do correct preallocation
3783:     */

3785:     /* first get start and end of "diagonal" columns */
3786:     if (csize == PETSC_DECIDE) {
3787:       PetscCall(ISGetSize(isrow, &mglobal));
3788:       if (mglobal == n) { /* square matrix */
3789:         nlocal = m;
3790:       } else {
3791:         nlocal = n / size + ((n % size) > rank);
3792:       }
3793:     } else {
3794:       nlocal = csize;
3795:     }
3796:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3797:     rstart = rend - nlocal;
3798:     PetscCheck(rank != size - 1 || rend == n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Local column sizes %" PetscInt_FMT " do not add up to total number of columns %" PetscInt_FMT, rend, n);

3800:     /* next, compute all the lengths */
3801:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3802:     olens = dlens + m;
3803:     for (i = 0; i < m; i++) {
3804:       jend = ii[i + 1] - ii[i];
3805:       olen = 0;
3806:       dlen = 0;
3807:       for (j = 0; j < jend; j++) {
3808:         if (*jj < rstart || *jj >= rend) olen++;
3809:         else dlen++;
3810:         jj++;
3811:       }
3812:       olens[i] = olen;
3813:       dlens[i] = dlen;
3814:     }
3815:     PetscCall(MatCreate(comm, &M));
3816:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3817:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3818:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3819:     PetscCall(MatSetOption(M, MAT_STRUCTURE_ONLY, mat->structure_only));
3820:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3821:     PetscCall(PetscFree(dlens));
3822:   } else {
3823:     PetscInt ml, nl;

3825:     M = *newmat;
3826:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3827:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3828:     PetscCall(MatZeroEntries(M));
3829:     /*
3830:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3831:        rather than the slower MatSetValues().
3832:     */
3833:     M->was_assembled = PETSC_TRUE;
3834:     M->assembled     = PETSC_FALSE;
3835:   }
3836:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3837:   aij = (Mat_SeqAIJ *)Mreuse->data;
3838:   ii  = aij->i;
3839:   jj  = aij->j;

3841:   /* trigger copy to CPU if needed */
3842:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3843:   for (i = 0; i < m; i++) {
3844:     row   = rstart + i;
3845:     nz    = ii[i + 1] - ii[i];
3846:     cwork = jj;
3847:     jj    = PetscSafePointerPlusOffset(jj, nz);
3848:     vwork = aa;
3849:     aa    = PetscSafePointerPlusOffset(aa, nz);
3850:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3851:   }
3852:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3854:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3855:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3856:   *newmat = M;

3858:   /* save submatrix used in processor for next request */
3859:   if (call == MAT_INITIAL_MATRIX) {
3860:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3861:     PetscCall(MatDestroy(&Mreuse));
3862:   }
3863:   PetscFunctionReturn(PETSC_SUCCESS);
3864: }

3866: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3867: {
3868:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3869:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii, irstart;
3870:   const PetscInt *JJ;
3871:   PetscBool       nooffprocentries;
3872:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3874:   PetscFunctionBegin;
3875:   PetscCall(PetscLayoutSetUp(B->rmap));
3876:   PetscCall(PetscLayoutSetUp(B->cmap));
3877:   m       = B->rmap->n;
3878:   cstart  = B->cmap->rstart;
3879:   cend    = B->cmap->rend;
3880:   rstart  = B->rmap->rstart;
3881:   irstart = Ii[0];

3883:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3885:   if (PetscDefined(USE_DEBUG)) {
3886:     for (i = 0; i < m; i++) {
3887:       nnz = Ii[i + 1] - Ii[i];
3888:       JJ  = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3889:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3890:       PetscCheck(!nnz || !(JJ[0] < 0), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Row %" PetscInt_FMT " starts with negative column index %" PetscInt_FMT, i, JJ[0]);
3891:       PetscCheck(!nnz || !(JJ[nnz - 1] >= B->cmap->N), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Row %" PetscInt_FMT " ends with too large a column index %" PetscInt_FMT " (max allowed %" PetscInt_FMT ")", i, JJ[nnz - 1], B->cmap->N);
3892:     }
3893:   }

3895:   for (i = 0; i < m; i++) {
3896:     nnz     = Ii[i + 1] - Ii[i];
3897:     JJ      = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3898:     nnz_max = PetscMax(nnz_max, nnz);
3899:     d       = 0;
3900:     for (j = 0; j < nnz; j++) {
3901:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3902:     }
3903:     d_nnz[i] = d;
3904:     o_nnz[i] = nnz - d;
3905:   }
3906:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3907:   PetscCall(PetscFree2(d_nnz, o_nnz));

3909:   for (i = 0; i < m; i++) {
3910:     ii = i + rstart;
3911:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i] - irstart), PetscSafePointerPlusOffset(v, Ii[i] - irstart), INSERT_VALUES));
3912:   }
3913:   nooffprocentries    = B->nooffprocentries;
3914:   B->nooffprocentries = PETSC_TRUE;
3915:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3916:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3917:   B->nooffprocentries = nooffprocentries;

3919:   /* count number of entries below block diagonal */
3920:   PetscCall(PetscFree(Aij->ld));
3921:   PetscCall(PetscCalloc1(m, &ld));
3922:   Aij->ld = ld;
3923:   for (i = 0; i < m; i++) {
3924:     nnz = Ii[i + 1] - Ii[i];
3925:     j   = 0;
3926:     while (j < nnz && J[j] < cstart) j++;
3927:     ld[i] = j;
3928:     if (J) J += nnz;
3929:   }

3931:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3932:   PetscFunctionReturn(PETSC_SUCCESS);
3933: }

3935: /*@
3936:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3937:   (the default parallel PETSc format).

3939:   Collective

3941:   Input Parameters:
3942: + B - the matrix
3943: . i - the indices into `j` for the start of each local row (indices start with zero)
3944: . j - the column indices for each local row (indices start with zero)
3945: - v - optional values in the matrix

3947:   Level: developer

3949:   Notes:
3950:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3951:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3952:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3954:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

3956:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

3958:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

3960:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
3961:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

3963:   The format which is used for the sparse matrix input, is equivalent to a
3964:   row-major ordering.. i.e for the following matrix, the input data expected is
3965:   as shown
3966: .vb
3967:         1 0 0
3968:         2 0 3     P0
3969:        -------
3970:         4 5 6     P1

3972:      Process0 [P0] rows_owned=[0,1]
3973:         i =  {0,1,3}  [size = nrow+1  = 2+1]
3974:         j =  {0,0,2}  [size = 3]
3975:         v =  {1,2,3}  [size = 3]

3977:      Process1 [P1] rows_owned=[2]
3978:         i =  {0,3}    [size = nrow+1  = 1+1]
3979:         j =  {0,1,2}  [size = 3]
3980:         v =  {4,5,6}  [size = 3]
3981: .ve

3983: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
3984:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
3985: @*/
3986: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
3987: {
3988:   PetscFunctionBegin;
3989:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
3990:   PetscFunctionReturn(PETSC_SUCCESS);
3991: }

3993: /*@
3994:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
3995:   (the default parallel PETSc format).  For good matrix assembly performance
3996:   the user should preallocate the matrix storage by setting the parameters
3997:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

3999:   Collective

4001:   Input Parameters:
4002: + B     - the matrix
4003: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4004:            (same value is used for all local rows)
4005: . d_nnz - array containing the number of nonzeros in the various rows of the
4006:            DIAGONAL portion of the local submatrix (possibly different for each row)
4007:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4008:            The size of this array is equal to the number of local rows, i.e 'm'.
4009:            For matrices that will be factored, you must leave room for (and set)
4010:            the diagonal entry even if it is zero.
4011: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4012:            submatrix (same value is used for all local rows).
4013: - o_nnz - array containing the number of nonzeros in the various rows of the
4014:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4015:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4016:            structure. The size of this array is equal to the number
4017:            of local rows, i.e 'm'.

4019:   Example Usage:
4020:   Consider the following 8x8 matrix with 34 non-zero values, that is
4021:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4022:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4023:   as follows

4025: .vb
4026:             1  2  0  |  0  3  0  |  0  4
4027:     Proc0   0  5  6  |  7  0  0  |  8  0
4028:             9  0 10  | 11  0  0  | 12  0
4029:     -------------------------------------
4030:            13  0 14  | 15 16 17  |  0  0
4031:     Proc1   0 18  0  | 19 20 21  |  0  0
4032:             0  0  0  | 22 23  0  | 24  0
4033:     -------------------------------------
4034:     Proc2  25 26 27  |  0  0 28  | 29  0
4035:            30  0  0  | 31 32 33  |  0 34
4036: .ve

4038:   This can be represented as a collection of submatrices as
4039: .vb
4040:       A B C
4041:       D E F
4042:       G H I
4043: .ve

4045:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4046:   owned by proc1, G,H,I are owned by proc2.

4048:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4049:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4050:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4052:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4053:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4054:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4055:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4056:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4057:   matrix, and [DF] as another `MATSEQAIJ` matrix.

4059:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4060:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4061:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4062:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4063:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4064:   In this case, the values of `d_nz`, `o_nz` are
4065: .vb
4066:      proc0  dnz = 2, o_nz = 2
4067:      proc1  dnz = 3, o_nz = 2
4068:      proc2  dnz = 1, o_nz = 4
4069: .ve
4070:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4071:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4072:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4073:   34 values.

4075:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4076:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4077:   In the above case the values for `d_nnz`, `o_nnz` are
4078: .vb
4079:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4080:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4081:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4082: .ve
4083:   Here the space allocated is sum of all the above values i.e 34, and
4084:   hence pre-allocation is perfect.

4086:   Level: intermediate

4088:   Notes:
4089:   If the *_nnz parameter is given then the *_nz parameter is ignored

4091:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4092:   storage.  The stored row and column indices begin with zero.
4093:   See [Sparse Matrices](sec_matsparse) for details.

4095:   The parallel matrix is partitioned such that the first m0 rows belong to
4096:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4097:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4099:   The DIAGONAL portion of the local submatrix of a processor can be defined
4100:   as the submatrix which is obtained by extraction the part corresponding to
4101:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4102:   first row that belongs to the processor, r2 is the last row belonging to
4103:   the this processor, and c1-c2 is range of indices of the local part of a
4104:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4105:   common case of a square matrix, the row and column ranges are the same and
4106:   the DIAGONAL part is also square. The remaining portion of the local
4107:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4109:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4111:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4112:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4113:   You can also run with the option `-info` and look for messages with the string
4114:   malloc in them to see if additional memory allocation was needed.

4116: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4117:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4118: @*/
4119: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4120: {
4121:   PetscFunctionBegin;
4124:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4125:   PetscFunctionReturn(PETSC_SUCCESS);
4126: }

4128: /*@
4129:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4130:   CSR format for the local rows.

4132:   Collective

4134:   Input Parameters:
4135: + comm - MPI communicator
4136: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4137: . n    - This value should be the same as the local size used in creating the
4138:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4139:          calculated if `N` is given) For square matrices n is almost always `m`.
4140: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4141: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4142: . i    - row indices (of length m+1); that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
4143: . j    - global column indices
4144: - a    - optional matrix values

4146:   Output Parameter:
4147: . mat - the matrix

4149:   Level: intermediate

4151:   Notes:
4152:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4153:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4154:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4156:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4158:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4160:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4161:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4163:   The format which is used for the sparse matrix input, is equivalent to a
4164:   row-major ordering, i.e., for the following matrix, the input data expected is
4165:   as shown
4166: .vb
4167:         1 0 0
4168:         2 0 3     P0
4169:        -------
4170:         4 5 6     P1

4172:      Process0 [P0] rows_owned=[0,1]
4173:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4174:         j =  {0,0,2}  [size = 3]
4175:         v =  {1,2,3}  [size = 3]

4177:      Process1 [P1] rows_owned=[2]
4178:         i =  {0,3}    [size = nrow+1  = 1+1]
4179:         j =  {0,1,2}  [size = 3]
4180:         v =  {4,5,6}  [size = 3]
4181: .ve

4183: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4184:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4185: @*/
4186: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4187: {
4188:   PetscFunctionBegin;
4189:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4190:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4191:   PetscCall(MatCreate(comm, mat));
4192:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4193:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4194:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4195:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4196:   PetscFunctionReturn(PETSC_SUCCESS);
4197: }

4199: /*@
4200:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4201:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4202:   from `MatCreateMPIAIJWithArrays()`

4204:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4206:   Collective

4208:   Input Parameters:
4209: + mat - the matrix
4210: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4211: . n   - This value should be the same as the local size used in creating the
4212:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4213:        calculated if N is given) For square matrices n is almost always m.
4214: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4215: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4216: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4217: . J   - column indices
4218: - v   - matrix values

4220:   Level: deprecated

4222: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4223:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4224: @*/
4225: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4226: {
4227:   PetscInt        nnz, i;
4228:   PetscBool       nooffprocentries;
4229:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4230:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4231:   PetscScalar    *ad, *ao;
4232:   PetscInt        ldi, Iii, md;
4233:   const PetscInt *Adi = Ad->i;
4234:   PetscInt       *ld  = Aij->ld;

4236:   PetscFunctionBegin;
4237:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4238:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4239:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4240:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4242:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4243:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4245:   for (i = 0; i < m; i++) {
4246:     if (PetscDefined(USE_DEBUG)) {
4247:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4248:         PetscCheck(J[j] >= J[j - 1], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column entry number %" PetscInt_FMT " (actual column %" PetscInt_FMT ") in row %" PetscInt_FMT " is not sorted", j - Ii[i], J[j], i);
4249:         PetscCheck(J[j] != J[j - 1], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column entry number %" PetscInt_FMT " (actual column %" PetscInt_FMT ") in row %" PetscInt_FMT " is identical to previous entry", j - Ii[i], J[j], i);
4250:       }
4251:     }
4252:     nnz = Ii[i + 1] - Ii[i];
4253:     Iii = Ii[i];
4254:     ldi = ld[i];
4255:     md  = Adi[i + 1] - Adi[i];
4256:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4257:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4258:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4259:     ad += md;
4260:     ao += nnz - md;
4261:   }
4262:   nooffprocentries      = mat->nooffprocentries;
4263:   mat->nooffprocentries = PETSC_TRUE;
4264:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4265:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4266:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4267:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4268:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4269:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4270:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4271:   mat->nooffprocentries = nooffprocentries;
4272:   PetscFunctionReturn(PETSC_SUCCESS);
4273: }

4275: /*@
4276:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4278:   Collective

4280:   Input Parameters:
4281: + mat - the matrix
4282: - v   - matrix values, stored by row

4284:   Level: intermediate

4286:   Notes:
4287:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4289:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4291: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4292:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4293: @*/
4294: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4295: {
4296:   PetscInt        nnz, i, m;
4297:   PetscBool       nooffprocentries;
4298:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4299:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4300:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4301:   PetscScalar    *ad, *ao;
4302:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4303:   PetscInt        ldi, Iii, md;
4304:   PetscInt       *ld = Aij->ld;

4306:   PetscFunctionBegin;
4307:   m = mat->rmap->n;

4309:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4310:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4311:   Iii = 0;
4312:   for (i = 0; i < m; i++) {
4313:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4314:     ldi = ld[i];
4315:     md  = Adi[i + 1] - Adi[i];
4316:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4317:     ad += md;
4318:     if (ao) {
4319:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4320:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4321:       ao += nnz - md;
4322:     }
4323:     Iii += nnz;
4324:   }
4325:   nooffprocentries      = mat->nooffprocentries;
4326:   mat->nooffprocentries = PETSC_TRUE;
4327:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4328:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4329:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4330:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4331:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4332:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4333:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4334:   mat->nooffprocentries = nooffprocentries;
4335:   PetscFunctionReturn(PETSC_SUCCESS);
4336: }

4338: /*@
4339:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4340:   (the default parallel PETSc format).  For good matrix assembly performance
4341:   the user should preallocate the matrix storage by setting the parameters
4342:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4344:   Collective

4346:   Input Parameters:
4347: + comm  - MPI communicator
4348: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4349:           This value should be the same as the local size used in creating the
4350:           y vector for the matrix-vector product y = Ax.
4351: . n     - This value should be the same as the local size used in creating the
4352:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4353:           calculated if N is given) For square matrices n is almost always m.
4354: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4355: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4356: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4357:           (same value is used for all local rows)
4358: . d_nnz - array containing the number of nonzeros in the various rows of the
4359:           DIAGONAL portion of the local submatrix (possibly different for each row)
4360:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4361:           The size of this array is equal to the number of local rows, i.e 'm'.
4362: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4363:           submatrix (same value is used for all local rows).
4364: - o_nnz - array containing the number of nonzeros in the various rows of the
4365:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4366:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4367:           structure. The size of this array is equal to the number
4368:           of local rows, i.e 'm'.

4370:   Output Parameter:
4371: . A - the matrix

4373:   Options Database Keys:
4374: + -mat_no_inode                   - Do not use inodes
4375: . -mat_inode_limit limit          - Sets inode limit (max limit=5)
4376: - -matmult_vecscatter_view viewer - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4377:                                     See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4378:                                     to be viewed as a matrix. Entry (i,j) is the size of message (in bytes) rank i sends to rank j in one `MatMult()` call.

4380:   Level: intermediate

4382:   Notes:
4383:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4384:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4385:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4387:   If the *_nnz parameter is given then the *_nz parameter is ignored

4389:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4390:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4391:   storage requirements for this matrix.

4393:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4394:   processor than it must be used on all processors that share the object for
4395:   that argument.

4397:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4398:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4400:   The user MUST specify either the local or global matrix dimensions
4401:   (possibly both).

4403:   The parallel matrix is partitioned across processors such that the
4404:   first `m0` rows belong to process 0, the next `m1` rows belong to
4405:   process 1, the next `m2` rows belong to process 2, etc., where
4406:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4407:   values corresponding to [m x N] submatrix.

4409:   The columns are logically partitioned with the n0 columns belonging
4410:   to 0th partition, the next n1 columns belonging to the next
4411:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4413:   The DIAGONAL portion of the local submatrix on any given processor
4414:   is the submatrix corresponding to the rows and columns m,n
4415:   corresponding to the given processor. i.e diagonal matrix on
4416:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4417:   etc. The remaining portion of the local submatrix [m x (N-n)]
4418:   constitute the OFF-DIAGONAL portion. The example below better
4419:   illustrates this concept. The two matrices, the DIAGONAL portion and
4420:   the OFF-DIAGONAL portion are each stored as `MATSEQAIJ` matrices.

4422:   For a square global matrix we define each processor's diagonal portion
4423:   to be its local rows and the corresponding columns (a square submatrix);
4424:   each processor's off-diagonal portion encompasses the remainder of the
4425:   local matrix (a rectangular submatrix).

4427:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4429:   When calling this routine with a single process communicator, a matrix of
4430:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4431:   type of communicator, use the construction mechanism
4432: .vb
4433:   MatCreate(..., &A);
4434:   MatSetType(A, MATMPIAIJ);
4435:   MatSetSizes(A, m, n, M, N);
4436:   MatMPIAIJSetPreallocation(A, ...);
4437: .ve

4439:   By default, this format uses inodes (identical nodes) when possible.
4440:   We search for consecutive rows with the same nonzero structure, thereby
4441:   reusing matrix information to achieve increased efficiency.

4443:   Example Usage:
4444:   Consider the following 8x8 matrix with 34 non-zero values, that is
4445:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4446:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4447:   as follows

4449: .vb
4450:             1  2  0  |  0  3  0  |  0  4
4451:     Proc0   0  5  6  |  7  0  0  |  8  0
4452:             9  0 10  | 11  0  0  | 12  0
4453:     -------------------------------------
4454:            13  0 14  | 15 16 17  |  0  0
4455:     Proc1   0 18  0  | 19 20 21  |  0  0
4456:             0  0  0  | 22 23  0  | 24  0
4457:     -------------------------------------
4458:     Proc2  25 26 27  |  0  0 28  | 29  0
4459:            30  0  0  | 31 32 33  |  0 34
4460: .ve

4462:   This can be represented as a collection of submatrices as

4464: .vb
4465:       A B C
4466:       D E F
4467:       G H I
4468: .ve

4470:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4471:   owned by proc1, G,H,I are owned by proc2.

4473:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4474:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4475:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4477:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4478:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4479:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4480:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4481:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4482:   matrix, and [DF] as another SeqAIJ matrix.

4484:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4485:   allocated for every row of the local DIAGONAL submatrix, and `o_nz`
4486:   storage locations are allocated for every row of the OFF-DIAGONAL submatrix.
4487:   One way to choose `d_nz` and `o_nz` is to use the maximum number of nonzeros over
4488:   the local rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4489:   In this case, the values of `d_nz`,`o_nz` are
4490: .vb
4491:      proc0  dnz = 2, o_nz = 2
4492:      proc1  dnz = 3, o_nz = 2
4493:      proc2  dnz = 1, o_nz = 4
4494: .ve
4495:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4496:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4497:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4498:   34 values.

4500:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4501:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4502:   In the above case the values for d_nnz,o_nnz are
4503: .vb
4504:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4505:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4506:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4507: .ve
4508:   Here the space allocated is sum of all the above values i.e 34, and
4509:   hence pre-allocation is perfect.

4511: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4512:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4513:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4514: @*/
4515: PetscErrorCode MatCreateAIJ(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[], Mat *A)
4516: {
4517:   PetscMPIInt size;

4519:   PetscFunctionBegin;
4520:   PetscCall(MatCreate(comm, A));
4521:   PetscCall(MatSetSizes(*A, m, n, M, N));
4522:   PetscCallMPI(MPI_Comm_size(comm, &size));
4523:   if (size > 1) {
4524:     PetscCall(MatSetType(*A, MATMPIAIJ));
4525:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4526:   } else {
4527:     PetscCall(MatSetType(*A, MATSEQAIJ));
4528:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4529:   }
4530:   PetscFunctionReturn(PETSC_SUCCESS);
4531: }

4533: /*@
4534:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4536:   Not Collective

4538:   Input Parameter:
4539: . A - The `MATMPIAIJ` matrix

4541:   Output Parameters:
4542: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4543: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4544: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4546:   Level: intermediate

4548:   Note:
4549:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4550:   in `Ad` are in [0, Nc) where Nc is the number of local columns. The columns are `Ao` are in [0, Nco), where Nco is
4551:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4552:   local column numbers to global column numbers in the original matrix.

4554: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4555: @*/
4556: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4557: {
4558:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4559:   PetscBool   flg;

4561:   PetscFunctionBegin;
4562:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4563:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4564:   if (Ad) *Ad = a->A;
4565:   if (Ao) *Ao = a->B;
4566:   if (colmap) *colmap = a->garray;
4567:   PetscFunctionReturn(PETSC_SUCCESS);
4568: }

4570: static PetscErrorCode MatGetMultPetscSF_MPIAIJ(Mat A, PetscSF *sf)
4571: {
4572:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

4574:   PetscFunctionBegin;
4575:   *sf = a->Mvctx;
4576:   PetscFunctionReturn(PETSC_SUCCESS);
4577: }

4579: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4580: {
4581:   PetscInt     m, N, i, rstart, nnz, Ii;
4582:   PetscInt    *indx;
4583:   PetscScalar *values;
4584:   MatType      rootType;

4586:   PetscFunctionBegin;
4587:   PetscCall(MatGetSize(inmat, &m, &N));
4588:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4589:     PetscInt *dnz, *onz, sum, bs, cbs;

4591:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4592:     /* Check sum(n) = N */
4593:     PetscCallMPI(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4594:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4596:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4597:     rstart -= m;

4599:     MatPreallocateBegin(comm, m, n, dnz, onz);
4600:     for (i = 0; i < m; i++) {
4601:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4602:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4603:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4604:     }

4606:     PetscCall(MatCreate(comm, outmat));
4607:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4608:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4609:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4610:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4611:     PetscCall(MatSetType(*outmat, rootType));
4612:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4613:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4614:     MatPreallocateEnd(dnz, onz);
4615:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4616:   }

4618:   /* numeric phase */
4619:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4620:   for (i = 0; i < m; i++) {
4621:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4622:     Ii = i + rstart;
4623:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4624:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4625:   }
4626:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4627:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4628:   PetscFunctionReturn(PETSC_SUCCESS);
4629: }

4631: static PetscErrorCode MatMergeSeqsToMPIDestroy(PetscCtxRt data)
4632: {
4633:   MatMergeSeqsToMPI *merge = *(MatMergeSeqsToMPI **)data;

4635:   PetscFunctionBegin;
4636:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4637:   PetscCall(PetscFree(merge->id_r));
4638:   PetscCall(PetscFree(merge->len_s));
4639:   PetscCall(PetscFree(merge->len_r));
4640:   PetscCall(PetscFree(merge->bi));
4641:   PetscCall(PetscFree(merge->bj));
4642:   PetscCall(PetscFree(merge->buf_ri[0]));
4643:   PetscCall(PetscFree(merge->buf_ri));
4644:   PetscCall(PetscFree(merge->buf_rj[0]));
4645:   PetscCall(PetscFree(merge->buf_rj));
4646:   PetscCall(PetscFree(merge->coi));
4647:   PetscCall(PetscFree(merge->coj));
4648:   PetscCall(PetscFree(merge->owners_co));
4649:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4650:   PetscCall(PetscFree(merge));
4651:   PetscFunctionReturn(PETSC_SUCCESS);
4652: }

4654: #include <../src/mat/utils/freespace.h>
4655: #include <petscbt.h>

4657: /*@
4658:   MatCreateMPIAIJSumSeqAIJNumeric - Fill the numerical values of an `MATMPIAIJ` matrix previously created by
4659:   `MatCreateMPIAIJSumSeqAIJSymbolic()` by summing the local `MATSEQAIJ` contributions from each process.

4661:   Collective

4663:   Input Parameters:
4664: + seqmat - the local `MATSEQAIJ` contribution from this process
4665: - mpimat - the target `MATMPIAIJ` matrix created by `MatCreateMPIAIJSumSeqAIJSymbolic()`

4667:   Level: developer

4669: .seealso: `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJSumSeqAIJSymbolic()`, `MatCreateMPIAIJSumSeqAIJ()`
4670: @*/
4671: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4672: {
4673:   MPI_Comm           comm;
4674:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4675:   PetscMPIInt        size, rank, taga, *len_s;
4676:   PetscInt           N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj, m;
4677:   PetscMPIInt        proc, k;
4678:   PetscInt         **buf_ri, **buf_rj;
4679:   PetscInt           anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4680:   PetscInt           nrows, **buf_ri_k, **nextrow, **nextai;
4681:   MPI_Request       *s_waits, *r_waits;
4682:   MPI_Status        *status;
4683:   const MatScalar   *aa, *a_a;
4684:   MatScalar        **abuf_r, *ba_i;
4685:   MatMergeSeqsToMPI *merge;
4686:   PetscContainer     container;

4688:   PetscFunctionBegin;
4689:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4690:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4692:   PetscCallMPI(MPI_Comm_size(comm, &size));
4693:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4695:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4696:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4697:   PetscCall(PetscContainerGetPointer(container, &merge));
4698:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4699:   aa = a_a;

4701:   bi     = merge->bi;
4702:   bj     = merge->bj;
4703:   buf_ri = merge->buf_ri;
4704:   buf_rj = merge->buf_rj;

4706:   PetscCall(PetscMalloc1(size, &status));
4707:   owners = merge->rowmap->range;
4708:   len_s  = merge->len_s;

4710:   /* send and recv matrix values */
4711:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4712:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4714:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4715:   for (proc = 0, k = 0; proc < size; proc++) {
4716:     if (!len_s[proc]) continue;
4717:     i = owners[proc];
4718:     PetscCallMPI(MPIU_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4719:     k++;
4720:   }

4722:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4723:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4724:   PetscCall(PetscFree(status));

4726:   PetscCall(PetscFree(s_waits));
4727:   PetscCall(PetscFree(r_waits));

4729:   /* insert mat values of mpimat */
4730:   PetscCall(PetscMalloc1(N, &ba_i));
4731:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4733:   for (k = 0; k < merge->nrecv; k++) {
4734:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4735:     nrows       = *buf_ri_k[k];
4736:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4737:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4738:   }

4740:   /* set values of ba */
4741:   m = merge->rowmap->n;
4742:   for (i = 0; i < m; i++) {
4743:     arow = owners[rank] + i;
4744:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4745:     bnzi = bi[i + 1] - bi[i];
4746:     PetscCall(PetscArrayzero(ba_i, bnzi));

4748:     /* add local non-zero vals of this proc's seqmat into ba */
4749:     anzi   = ai[arow + 1] - ai[arow];
4750:     aj     = a->j + ai[arow];
4751:     aa     = a_a + ai[arow];
4752:     nextaj = 0;
4753:     for (j = 0; nextaj < anzi; j++) {
4754:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4755:         ba_i[j] += aa[nextaj++];
4756:       }
4757:     }

4759:     /* add received vals into ba */
4760:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4761:       /* i-th row */
4762:       if (i == *nextrow[k]) {
4763:         anzi   = *(nextai[k] + 1) - *nextai[k];
4764:         aj     = buf_rj[k] + *nextai[k];
4765:         aa     = abuf_r[k] + *nextai[k];
4766:         nextaj = 0;
4767:         for (j = 0; nextaj < anzi; j++) {
4768:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4769:             ba_i[j] += aa[nextaj++];
4770:           }
4771:         }
4772:         nextrow[k]++;
4773:         nextai[k]++;
4774:       }
4775:     }
4776:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4777:   }
4778:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4779:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4780:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4782:   PetscCall(PetscFree(abuf_r[0]));
4783:   PetscCall(PetscFree(abuf_r));
4784:   PetscCall(PetscFree(ba_i));
4785:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4786:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4787:   PetscFunctionReturn(PETSC_SUCCESS);
4788: }

4790: /*@
4791:   MatCreateMPIAIJSumSeqAIJSymbolic - Create the symbolic (nonzero-pattern) portion of an `MATMPIAIJ` matrix
4792:   obtained by summing local `MATSEQAIJ` contributions from each process.

4794:   Collective

4796:   Input Parameters:
4797: + comm   - the communicator
4798: . seqmat - the local `MATSEQAIJ` contribution from this process
4799: . m      - the number of local rows for the resulting `MATMPIAIJ` matrix, or `PETSC_DECIDE`
4800: - n      - the number of local columns for the resulting `MATMPIAIJ` matrix, or `PETSC_DECIDE`

4802:   Output Parameter:
4803: . mpimat - the newly created `MATMPIAIJ` matrix

4805:   Level: developer

4807:   Note:
4808:   The numerical values are filled in by a subsequent call to `MatCreateMPIAIJSumSeqAIJNumeric()`.

4810: .seealso: `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJSumSeqAIJNumeric()`, `MatCreateMPIAIJSumSeqAIJ()`
4811: @*/
4812: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4813: {
4814:   Mat                B_mpi;
4815:   Mat_SeqAIJ        *a = (Mat_SeqAIJ *)seqmat->data;
4816:   PetscMPIInt        size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4817:   PetscInt         **buf_rj, **buf_ri, **buf_ri_k;
4818:   PetscInt           M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4819:   PetscInt           len, *dnz, *onz, bs, cbs;
4820:   PetscInt           k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4821:   PetscInt           nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4822:   MPI_Request       *si_waits, *sj_waits, *ri_waits, *rj_waits;
4823:   MPI_Status        *status;
4824:   PetscFreeSpaceList free_space = NULL, current_space = NULL;
4825:   PetscBT            lnkbt;
4826:   MatMergeSeqsToMPI *merge;
4827:   PetscContainer     container;

4829:   PetscFunctionBegin;
4830:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4832:   /* make sure it is a PETSc comm */
4833:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4834:   PetscCallMPI(MPI_Comm_size(comm, &size));
4835:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4837:   PetscCall(PetscNew(&merge));
4838:   PetscCall(PetscMalloc1(size, &status));

4840:   /* determine row ownership */
4841:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4842:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4843:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4844:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4845:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4846:   PetscCall(PetscMalloc1(size, &len_si));
4847:   PetscCall(PetscMalloc1(size, &merge->len_s));

4849:   m      = merge->rowmap->n;
4850:   owners = merge->rowmap->range;

4852:   /* determine the number of messages to send, their lengths */
4853:   len_s = merge->len_s;

4855:   len          = 0; /* length of buf_si[] */
4856:   merge->nsend = 0;
4857:   for (PetscMPIInt proc = 0; proc < size; proc++) {
4858:     len_si[proc] = 0;
4859:     if (proc == rank) {
4860:       len_s[proc] = 0;
4861:     } else {
4862:       PetscCall(PetscMPIIntCast(owners[proc + 1] - owners[proc] + 1, &len_si[proc]));
4863:       PetscCall(PetscMPIIntCast(ai[owners[proc + 1]] - ai[owners[proc]], &len_s[proc])); /* num of rows to be sent to [proc] */
4864:     }
4865:     if (len_s[proc]) {
4866:       merge->nsend++;
4867:       nrows = 0;
4868:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4869:         if (ai[i + 1] > ai[i]) nrows++;
4870:       }
4871:       PetscCall(PetscMPIIntCast(2 * (nrows + 1), &len_si[proc]));
4872:       len += len_si[proc];
4873:     }
4874:   }

4876:   /* determine the number and length of messages to receive for ij-structure */
4877:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4878:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4880:   /* post the Irecv of j-structure */
4881:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4882:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4884:   /* post the Isend of j-structure */
4885:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4887:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4888:     if (!len_s[proc]) continue;
4889:     i = owners[proc];
4890:     PetscCallMPI(MPIU_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4891:     k++;
4892:   }

4894:   /* receives and sends of j-structure are complete */
4895:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4896:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4898:   /* send and recv i-structure */
4899:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4900:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4902:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4903:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4904:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4905:     if (!len_s[proc]) continue;
4906:     /* form outgoing message for i-structure:
4907:          buf_si[0]:                 nrows to be sent
4908:                [1:nrows]:           row index (global)
4909:                [nrows+1:2*nrows+1]: i-structure index
4910:     */
4911:     nrows       = len_si[proc] / 2 - 1;
4912:     buf_si_i    = buf_si + nrows + 1;
4913:     buf_si[0]   = nrows;
4914:     buf_si_i[0] = 0;
4915:     nrows       = 0;
4916:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4917:       anzi = ai[i + 1] - ai[i];
4918:       if (anzi) {
4919:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4920:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4921:         nrows++;
4922:       }
4923:     }
4924:     PetscCallMPI(MPIU_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4925:     k++;
4926:     buf_si += len_si[proc];
4927:   }

4929:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4930:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4932:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4933:   for (i = 0; i < merge->nrecv; i++) PetscCall(PetscInfo(seqmat, "recv len_ri=%d, len_rj=%d from [%d]\n", len_ri[i], merge->len_r[i], merge->id_r[i]));

4935:   PetscCall(PetscFree(len_si));
4936:   PetscCall(PetscFree(len_ri));
4937:   PetscCall(PetscFree(rj_waits));
4938:   PetscCall(PetscFree2(si_waits, sj_waits));
4939:   PetscCall(PetscFree(ri_waits));
4940:   PetscCall(PetscFree(buf_s));
4941:   PetscCall(PetscFree(status));

4943:   /* compute a local seq matrix in each processor */
4944:   /* allocate bi array and free space for accumulating nonzero column info */
4945:   PetscCall(PetscMalloc1(m + 1, &bi));
4946:   bi[0] = 0;

4948:   /* create and initialize a linked list */
4949:   nlnk = N + 1;
4950:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4952:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4953:   len = ai[owners[rank + 1]] - ai[owners[rank]];
4954:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

4956:   current_space = free_space;

4958:   /* determine symbolic info for each local row */
4959:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4961:   for (k = 0; k < merge->nrecv; k++) {
4962:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4963:     nrows       = *buf_ri_k[k];
4964:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4965:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4966:   }

4968:   MatPreallocateBegin(comm, m, n, dnz, onz);
4969:   len = 0;
4970:   for (i = 0; i < m; i++) {
4971:     bnzi = 0;
4972:     /* add local non-zero cols of this proc's seqmat into lnk */
4973:     arow = owners[rank] + i;
4974:     anzi = ai[arow + 1] - ai[arow];
4975:     aj   = a->j + ai[arow];
4976:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4977:     bnzi += nlnk;
4978:     /* add received col data into lnk */
4979:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4980:       if (i == *nextrow[k]) {            /* i-th row */
4981:         anzi = *(nextai[k] + 1) - *nextai[k];
4982:         aj   = buf_rj[k] + *nextai[k];
4983:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
4984:         bnzi += nlnk;
4985:         nextrow[k]++;
4986:         nextai[k]++;
4987:       }
4988:     }
4989:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

4991:     /* if free space is not available, make more free space */
4992:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
4993:     /* copy data into free space, then initialize lnk */
4994:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
4995:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

4997:     current_space->array += bnzi;
4998:     current_space->local_used += bnzi;
4999:     current_space->local_remaining -= bnzi;

5001:     bi[i + 1] = bi[i] + bnzi;
5002:   }

5004:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

5006:   PetscCall(PetscMalloc1(bi[m], &bj));
5007:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
5008:   PetscCall(PetscLLDestroy(lnk, lnkbt));

5010:   /* create symbolic parallel matrix B_mpi */
5011:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
5012:   PetscCall(MatCreate(comm, &B_mpi));
5013:   if (n == PETSC_DECIDE) PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
5014:   else PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
5015:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
5016:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
5017:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
5018:   MatPreallocateEnd(dnz, onz);
5019:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

5021:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5022:   B_mpi->assembled = PETSC_FALSE;
5023:   merge->bi        = bi;
5024:   merge->bj        = bj;
5025:   merge->buf_ri    = buf_ri;
5026:   merge->buf_rj    = buf_rj;
5027:   merge->coi       = NULL;
5028:   merge->coj       = NULL;
5029:   merge->owners_co = NULL;

5031:   PetscCall(PetscCommDestroy(&comm));

5033:   /* attach the supporting struct to B_mpi for reuse */
5034:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5035:   PetscCall(PetscContainerSetPointer(container, merge));
5036:   PetscCall(PetscContainerSetCtxDestroy(container, MatMergeSeqsToMPIDestroy));
5037:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5038:   PetscCall(PetscContainerDestroy(&container));
5039:   *mpimat = B_mpi;

5041:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5042:   PetscFunctionReturn(PETSC_SUCCESS);
5043: }

5045: /*@
5046:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5047:   matrices from each processor

5049:   Collective

5051:   Input Parameters:
5052: + comm   - the communicators the parallel matrix will live on
5053: . seqmat - the input sequential matrices
5054: . m      - number of local rows (or `PETSC_DECIDE`)
5055: . n      - number of local columns (or `PETSC_DECIDE`)
5056: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5058:   Output Parameter:
5059: . mpimat - the parallel matrix generated

5061:   Level: advanced

5063:   Note:
5064:   The dimensions of the sequential matrix in each processor MUST be the same.
5065:   The input seqmat is included into the container `MatMergeSeqsToMPIDestroy`, and will be
5066:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5068: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5069: @*/
5070: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5071: {
5072:   PetscMPIInt size;

5074:   PetscFunctionBegin;
5075:   PetscCallMPI(MPI_Comm_size(comm, &size));
5076:   if (size == 1) {
5077:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5078:     if (scall == MAT_INITIAL_MATRIX) PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5079:     else PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5080:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5081:     PetscFunctionReturn(PETSC_SUCCESS);
5082:   }
5083:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5084:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5085:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5086:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5087:   PetscFunctionReturn(PETSC_SUCCESS);
5088: }

5090: /*@
5091:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5093:   Not Collective

5095:   Input Parameter:
5096: . A - the matrix

5098:   Output Parameter:
5099: . A_loc - the local sequential matrix generated

5101:   Level: developer

5103:   Notes:
5104:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5105:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5106:   `n` is the global column count obtained with `MatGetSize()`

5108:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5110:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5112:   Destroy the matrix with `MatDestroy()`

5114: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5115: @*/
5116: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5117: {
5118:   PetscBool mpi;

5120:   PetscFunctionBegin;
5121:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5122:   if (mpi) PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5123:   else {
5124:     *A_loc = A;
5125:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5126:   }
5127:   PetscFunctionReturn(PETSC_SUCCESS);
5128: }

5130: /*@
5131:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5133:   Not Collective

5135:   Input Parameters:
5136: + A     - the matrix
5137: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5139:   Output Parameter:
5140: . A_loc - the local sequential matrix generated

5142:   Level: developer

5144:   Notes:
5145:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5146:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5147:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5149:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5151:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5152:   with its reference count increased by one. Hence changing values of `A_loc` changes `A`. If `MAT_REUSE_MATRIX` is requested on a sequential matrix
5153:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5154:   and then call this routine with `MAT_REUSE_MATRIX`. In this case, one can modify the values of `A_loc` without affecting the original sequential matrix.

5156: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5157: @*/
5158: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5159: {
5160:   PetscFunctionBegin;
5161:   PetscCall(MatMPIAIJGetLocalMat_Private(A, scall, PETSC_FALSE, A_loc));
5162:   PetscFunctionReturn(PETSC_SUCCESS);
5163: }

5165: PetscErrorCode MatMPIAIJGetLocalMat_Private(Mat A, MatReuse scall, PetscBool structure_only, Mat *A_loc)
5166: {
5167:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5168:   Mat_SeqAIJ        *mat, *a, *b;
5169:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5170:   const PetscScalar *aa, *ba, *aav = NULL, *bav = NULL;
5171:   PetscScalar       *ca = NULL, *cam;
5172:   PetscMPIInt        size;
5173:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5174:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5175:   PetscBool          match;

5177:   PetscFunctionBegin;
5178:   PetscCheck(!structure_only || scall == MAT_INITIAL_MATRIX, PETSC_COMM_SELF, PETSC_ERR_SUP, "Structure-only extraction requires MAT_INITIAL_MATRIX");
5179:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5180:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5181:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5182:   if (size == 1 && !structure_only) {
5183:     if (scall == MAT_INITIAL_MATRIX) {
5184:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5185:       *A_loc = mpimat->A;
5186:     } else if (scall == MAT_REUSE_MATRIX) PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5187:     PetscFunctionReturn(PETSC_SUCCESS);
5188:   }

5190:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5191:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5192:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5193:   ai = a->i;
5194:   aj = a->j;
5195:   bi = b->i;
5196:   bj = b->j;
5197:   if (!structure_only) {
5198:     PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5199:     PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5200:   }
5201:   aa = aav;
5202:   ba = bav;
5203:   if (scall == MAT_INITIAL_MATRIX) {
5204:     PetscCall(PetscMalloc1(1 + am, &ci));
5205:     ci[0] = 0;
5206:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5207:     PetscCall(PetscMalloc1(ci[am], &cj));
5208:     if (!structure_only) PetscCall(PetscMalloc1(ci[am], &ca));
5209:     k = 0;
5210:     for (i = 0; i < am; i++) {
5211:       ncols_o = bi[i + 1] - bi[i];
5212:       ncols_d = ai[i + 1] - ai[i];
5213:       /* off-diagonal portion of A */
5214:       for (jo = 0; jo < ncols_o; jo++, bj++, k++) {
5215:         col = cmap[*bj];
5216:         if (col >= cstart) break;
5217:         cj[k] = col;
5218:         if (!structure_only) ca[k] = *ba++;
5219:       }
5220:       /* diagonal portion of A */
5221:       for (j = 0; j < ncols_d; j++, k++) {
5222:         cj[k] = cstart + *aj++;
5223:         if (!structure_only) ca[k] = *aa++;
5224:       }
5225:       /* off-diagonal portion of A */
5226:       for (j = jo; j < ncols_o; j++, k++) {
5227:         cj[k] = cmap[*bj++];
5228:         if (!structure_only) ca[k] = *ba++;
5229:       }
5230:     }
5231:     /* put together the new matrix */
5232:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5233:     PetscCall(MatSetOption(*A_loc, MAT_STRUCTURE_ONLY, structure_only));
5234:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5235:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5236:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5237:     mat->free_a  = PETSC_TRUE;
5238:     mat->free_ij = PETSC_TRUE;
5239:     mat->nonew   = 0;
5240:   } else if (scall == MAT_REUSE_MATRIX) {
5241:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5242:     ci  = mat->i;
5243:     cj  = mat->j;
5244:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5245:     for (i = 0; i < am; i++) {
5246:       /* off-diagonal portion of A */
5247:       ncols_o = bi[i + 1] - bi[i];
5248:       for (jo = 0; jo < ncols_o; jo++, bj++) {
5249:         col = cmap[*bj];
5250:         if (col >= cstart) break;
5251:         *cam++ = *ba++;
5252:       }
5253:       /* diagonal portion of A */
5254:       ncols_d = ai[i + 1] - ai[i];
5255:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5256:       /* off-diagonal portion of A */
5257:       for (j = jo; j < ncols_o; j++, bj++) *cam++ = *ba++;
5258:     }
5259:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5260:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5261:   if (!structure_only) {
5262:     PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5263:     PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5264:   }
5265:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5266:   PetscFunctionReturn(PETSC_SUCCESS);
5267: }

5269: /*@
5270:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5271:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5273:   Not Collective

5275:   Input Parameters:
5276: + A     - the matrix
5277: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5279:   Output Parameters:
5280: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5281: - A_loc - the local sequential matrix generated

5283:   Level: developer

5285:   Note:
5286:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5287:   part, then those associated with the off-diagonal part (in its local ordering)

5289: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5290: @*/
5291: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5292: {
5293:   Mat             Ao, Ad;
5294:   const PetscInt *cmap;
5295:   PetscMPIInt     size;
5296:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5298:   PetscFunctionBegin;
5299:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5300:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5301:   if (size == 1) {
5302:     if (scall == MAT_INITIAL_MATRIX) {
5303:       PetscCall(PetscObjectReference((PetscObject)Ad));
5304:       *A_loc = Ad;
5305:     } else if (scall == MAT_REUSE_MATRIX) {
5306:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5307:     }
5308:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5309:     PetscFunctionReturn(PETSC_SUCCESS);
5310:   }
5311:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5312:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5313:   if (f) PetscCall((*f)(A, scall, glob, A_loc));
5314:   else {
5315:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5316:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5317:     Mat_SeqAIJ        *c;
5318:     PetscInt          *ai = a->i, *aj = a->j;
5319:     PetscInt          *bi = b->i, *bj = b->j;
5320:     PetscInt          *ci, *cj;
5321:     const PetscScalar *aa, *ba;
5322:     PetscScalar       *ca;
5323:     PetscInt           i, j, am, dn, on;

5325:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5326:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5327:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5328:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5329:     if (scall == MAT_INITIAL_MATRIX) {
5330:       PetscInt k;
5331:       PetscCall(PetscMalloc1(1 + am, &ci));
5332:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5333:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5334:       ci[0] = 0;
5335:       for (i = 0, k = 0; i < am; i++) {
5336:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5337:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5338:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5339:         /* diagonal portion of A */
5340:         for (j = 0; j < ncols_d; j++, k++) {
5341:           cj[k] = *aj++;
5342:           ca[k] = *aa++;
5343:         }
5344:         /* off-diagonal portion of A */
5345:         for (j = 0; j < ncols_o; j++, k++) {
5346:           cj[k] = dn + *bj++;
5347:           ca[k] = *ba++;
5348:         }
5349:       }
5350:       /* put together the new matrix */
5351:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5352:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5353:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5354:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5355:       c->free_a  = PETSC_TRUE;
5356:       c->free_ij = PETSC_TRUE;
5357:       c->nonew   = 0;
5358:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5359:     } else if (scall == MAT_REUSE_MATRIX) {
5360:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5361:       for (i = 0; i < am; i++) {
5362:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5363:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5364:         /* diagonal portion of A */
5365:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5366:         /* off-diagonal portion of A */
5367:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5368:       }
5369:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5370:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5371:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5372:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5373:     if (glob) {
5374:       PetscInt cst, *gidx;

5376:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5377:       PetscCall(PetscMalloc1(dn + on, &gidx));
5378:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5379:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5380:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5381:     }
5382:   }
5383:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5384:   PetscFunctionReturn(PETSC_SUCCESS);
5385: }

5387: /*@
5388:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5390:   Not Collective

5392:   Input Parameters:
5393: + A     - the matrix
5394: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5395: . row   - index set of rows to extract (or `NULL`)
5396: - col   - index set of columns to extract (or `NULL`)

5398:   Output Parameter:
5399: . A_loc - the local sequential matrix generated

5401:   Level: developer

5403: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5404: @*/
5405: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5406: {
5407:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5408:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5409:   IS          isrowa, iscola;
5410:   Mat        *aloc;
5411:   PetscBool   match;

5413:   PetscFunctionBegin;
5414:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5415:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5416:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5417:   if (!row) {
5418:     start = A->rmap->rstart;
5419:     end   = A->rmap->rend;
5420:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5421:   } else {
5422:     isrowa = *row;
5423:   }
5424:   if (!col) {
5425:     start = A->cmap->rstart;
5426:     cmap  = a->garray;
5427:     nzA   = a->A->cmap->n;
5428:     nzB   = a->B->cmap->n;
5429:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5430:     ncols = 0;
5431:     for (i = 0; i < nzB; i++) {
5432:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5433:       else break;
5434:     }
5435:     imark = i;
5436:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5437:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5438:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5439:   } else iscola = *col;
5440:   if (scall != MAT_INITIAL_MATRIX) {
5441:     PetscCall(PetscMalloc1(1, &aloc));
5442:     aloc[0] = *A_loc;
5443:   }
5444:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5445:   if (!col) { /* attach global id of condensed columns */
5446:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5447:   }
5448:   *A_loc = aloc[0];
5449:   PetscCall(PetscFree(aloc));
5450:   if (!row) PetscCall(ISDestroy(&isrowa));
5451:   if (!col) PetscCall(ISDestroy(&iscola));
5452:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5453:   PetscFunctionReturn(PETSC_SUCCESS);
5454: }

5456: /*
5457:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5458:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5459:  * on a global size.
5460:  * */
5461: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5462: {
5463:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5464:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5465:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5466:   PetscMPIInt            owner;
5467:   PetscSFNode           *iremote, *oiremote;
5468:   const PetscInt        *lrowindices;
5469:   PetscSF                sf, osf;
5470:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5471:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5472:   MPI_Comm               comm;
5473:   ISLocalToGlobalMapping mapping;
5474:   const PetscScalar     *pd_a, *po_a;

5476:   PetscFunctionBegin;
5477:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5478:   /* plocalsize is the number of roots
5479:    * nrows is the number of leaves
5480:    * */
5481:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5482:   PetscCall(ISGetLocalSize(rows, &nrows));
5483:   PetscCall(PetscCalloc1(nrows, &iremote));
5484:   PetscCall(ISGetIndices(rows, &lrowindices));
5485:   for (i = 0; i < nrows; i++) {
5486:     /* Find a remote index and an owner for a row
5487:      * The row could be local or remote
5488:      * */
5489:     owner = 0;
5490:     lidx  = 0;
5491:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5492:     iremote[i].index = lidx;
5493:     iremote[i].rank  = owner;
5494:   }
5495:   /* Create SF to communicate how many nonzero columns for each row */
5496:   PetscCall(PetscSFCreate(comm, &sf));
5497:   /* SF will figure out the number of nonzero columns for each row, and their
5498:    * offsets
5499:    * */
5500:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5501:   PetscCall(PetscSFSetFromOptions(sf));
5502:   PetscCall(PetscSFSetUp(sf));

5504:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5505:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5506:   PetscCall(PetscCalloc1(nrows, &pnnz));
5507:   roffsets[0] = 0;
5508:   roffsets[1] = 0;
5509:   for (i = 0; i < plocalsize; i++) {
5510:     /* diagonal */
5511:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5512:     /* off-diagonal */
5513:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5514:     /* compute offsets so that we relative location for each row */
5515:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5516:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5517:   }
5518:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5519:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5520:   /* 'r' means root, and 'l' means leaf */
5521:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5522:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5523:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5524:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5525:   PetscCall(PetscSFDestroy(&sf));
5526:   PetscCall(PetscFree(roffsets));
5527:   PetscCall(PetscFree(nrcols));
5528:   dntotalcols = 0;
5529:   ontotalcols = 0;
5530:   ncol        = 0;
5531:   for (i = 0; i < nrows; i++) {
5532:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5533:     ncol    = PetscMax(pnnz[i], ncol);
5534:     /* diagonal */
5535:     dntotalcols += nlcols[i * 2 + 0];
5536:     /* off-diagonal */
5537:     ontotalcols += nlcols[i * 2 + 1];
5538:   }
5539:   /* We do not need to figure the right number of columns
5540:    * since all the calculations will be done by going through the raw data
5541:    * */
5542:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5543:   PetscCall(MatSetUp(*P_oth));
5544:   PetscCall(PetscFree(pnnz));
5545:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5546:   /* diagonal */
5547:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5548:   /* off-diagonal */
5549:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5550:   /* diagonal */
5551:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5552:   /* off-diagonal */
5553:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5554:   dntotalcols = 0;
5555:   ontotalcols = 0;
5556:   ntotalcols  = 0;
5557:   for (i = 0; i < nrows; i++) {
5558:     owner = 0;
5559:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5560:     /* Set iremote for diag matrix */
5561:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5562:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5563:       iremote[dntotalcols].rank  = owner;
5564:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5565:       ilocal[dntotalcols++] = ntotalcols++;
5566:     }
5567:     /* off-diagonal */
5568:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5569:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5570:       oiremote[ontotalcols].rank  = owner;
5571:       oilocal[ontotalcols++]      = ntotalcols++;
5572:     }
5573:   }
5574:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5575:   PetscCall(PetscFree(loffsets));
5576:   PetscCall(PetscFree(nlcols));
5577:   PetscCall(PetscSFCreate(comm, &sf));
5578:   /* P serves as roots and P_oth is leaves
5579:    * Diag matrix
5580:    * */
5581:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5582:   PetscCall(PetscSFSetFromOptions(sf));
5583:   PetscCall(PetscSFSetUp(sf));

5585:   PetscCall(PetscSFCreate(comm, &osf));
5586:   /* off-diagonal */
5587:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5588:   PetscCall(PetscSFSetFromOptions(osf));
5589:   PetscCall(PetscSFSetUp(osf));
5590:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5591:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5592:   /* operate on the matrix internal data to save memory */
5593:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5594:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5595:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5596:   /* Convert to global indices for diag matrix */
5597:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5598:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5599:   /* We want P_oth store global indices */
5600:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5601:   /* Use memory scalable approach */
5602:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5603:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5604:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5605:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5606:   /* Convert back to local indices */
5607:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5608:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5609:   nout = 0;
5610:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5611:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5612:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5613:   /* Exchange values */
5614:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5615:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5616:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5617:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5618:   /* Stop PETSc from shrinking memory */
5619:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5620:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5621:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5622:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5623:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5624:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5625:   PetscCall(PetscSFDestroy(&sf));
5626:   PetscCall(PetscSFDestroy(&osf));
5627:   PetscFunctionReturn(PETSC_SUCCESS);
5628: }

5630: /*
5631:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5632:  * This supports MPIAIJ and MAIJ
5633:  * */
5634: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5635: {
5636:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5637:   Mat_SeqAIJ *p_oth;
5638:   IS          rows, map;
5639:   PetscHMapI  hamp;
5640:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5641:   MPI_Comm    comm;
5642:   PetscSF     sf, osf;
5643:   PetscBool   has;

5645:   PetscFunctionBegin;
5646:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5647:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5648:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5649:    *  and then create a submatrix (that often is an overlapping matrix)
5650:    * */
5651:   if (reuse == MAT_INITIAL_MATRIX) {
5652:     /* Use a hash table to figure out unique keys */
5653:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5654:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5655:     count = 0;
5656:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5657:     for (i = 0; i < a->B->cmap->n; i++) {
5658:       key = a->garray[i] / dof;
5659:       PetscCall(PetscHMapIHas(hamp, key, &has));
5660:       if (!has) {
5661:         mapping[i] = count;
5662:         PetscCall(PetscHMapISet(hamp, key, count++));
5663:       } else {
5664:         /* Current 'i' has the same value the previous step */
5665:         mapping[i] = count - 1;
5666:       }
5667:     }
5668:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5669:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5670:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5671:     PetscCall(PetscCalloc1(htsize, &rowindices));
5672:     off = 0;
5673:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5674:     PetscCall(PetscHMapIDestroy(&hamp));
5675:     PetscCall(PetscSortInt(htsize, rowindices));
5676:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5677:     /* In case, the matrix was already created but users want to recreate the matrix */
5678:     PetscCall(MatDestroy(P_oth));
5679:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5680:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5681:     PetscCall(ISDestroy(&map));
5682:     PetscCall(ISDestroy(&rows));
5683:   } else if (reuse == MAT_REUSE_MATRIX) {
5684:     /* If matrix was already created, we simply update values using SF objects
5685:      * that as attached to the matrix earlier.
5686:      */
5687:     const PetscScalar *pd_a, *po_a;

5689:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5690:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5691:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5692:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5693:     /* Update values in place */
5694:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5695:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5696:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5697:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5698:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5699:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5700:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5701:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5702:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5703:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5704:   PetscFunctionReturn(PETSC_SUCCESS);
5705: }

5707: /*@
5708:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5710:   Collective

5712:   Input Parameters:
5713: + A     - the first matrix in `MATMPIAIJ` format
5714: . B     - the second matrix in `MATMPIAIJ` format
5715: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5717:   Output Parameters:
5718: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5719: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5720: - B_seq - the sequential matrix generated

5722:   Level: developer

5724: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5725: @*/
5726: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5727: {
5728:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5729:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5730:   IS          isrowb, iscolb;
5731:   Mat        *bseq = NULL;

5733:   PetscFunctionBegin;
5734:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
5735:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5736:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5738:   if (scall == MAT_INITIAL_MATRIX) {
5739:     start = A->cmap->rstart;
5740:     cmap  = a->garray;
5741:     nzA   = a->A->cmap->n;
5742:     nzB   = a->B->cmap->n;
5743:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5744:     ncols = 0;
5745:     for (i = 0; i < nzB; i++) { /* row < local row index */
5746:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5747:       else break;
5748:     }
5749:     imark = i;
5750:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5751:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5752:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5753:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5754:   } else {
5755:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5756:     isrowb = *rowb;
5757:     iscolb = *colb;
5758:     PetscCall(PetscMalloc1(1, &bseq));
5759:     bseq[0] = *B_seq;
5760:   }
5761:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5762:   *B_seq = bseq[0];
5763:   PetscCall(PetscFree(bseq));
5764:   if (!rowb) {
5765:     PetscCall(ISDestroy(&isrowb));
5766:   } else {
5767:     *rowb = isrowb;
5768:   }
5769:   if (!colb) {
5770:     PetscCall(ISDestroy(&iscolb));
5771:   } else {
5772:     *colb = iscolb;
5773:   }
5774:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5775:   PetscFunctionReturn(PETSC_SUCCESS);
5776: }

5778: // PetscClangLinter pragma disable: -fdoc-sowing-chars
5779: /*
5780:   MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5781:   of the OFF-DIAGONAL portion of local A

5783:   Collective

5785:   Input Parameters:
5786: + A     - the first matrix in `MATMPIAIJ` format
5787: . B     - the second matrix in `MATMPIAIJ` format
5788: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5790:   Output Parameters:
5791: + startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5792: . startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5793: . bufa_ptr  - array for sending matrix values, saved for MAT_REUSE (or NULL)
5794: - B_oth     - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5796:   Level: developer

5798:   Developer Note:
5799:   This directly accesses information inside the VecScatter associated with the matrix-vector product
5800:   for this matrix. This is not desirable.

5802: .seealso: [](ch_mat), `Mat`, `MATMPIAIJ`
5803: */
5804: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5805: {
5806:   PetscFunctionBegin;
5807:   PetscCall(MatGetBrowsOfAoCols_MPIAIJ_Private(A, B, scall, PETSC_FALSE, startsj_s, startsj_r, bufa_ptr, B_oth));
5808:   PetscFunctionReturn(PETSC_SUCCESS);
5809: }

5811: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ_Private(Mat A, Mat B, MatReuse scall, PetscBool structure_only, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5812: {
5813:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5814:   VecScatter         ctx;
5815:   MPI_Comm           comm;
5816:   const PetscMPIInt *rprocs, *sprocs;
5817:   PetscMPIInt        nrecvs, nsends;
5818:   const PetscInt    *srow, *rstarts, *sstarts;
5819:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5820:   PetscInt           i, j, k = 0, l, ll, nrows, *rstartsj = NULL, *sstartsj, len;
5821:   PetscScalar       *b_otha = NULL, *bufa = NULL, *bufA, *vals = NULL;
5822:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5823:   PetscMPIInt        size, tag, rank, nreqs;

5825:   PetscFunctionBegin;
5826:   PetscCheck(!structure_only || scall == MAT_INITIAL_MATRIX, PETSC_COMM_SELF, PETSC_ERR_SUP, "Structure-only extraction requires MAT_INITIAL_MATRIX");
5827:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5828:   PetscCallMPI(MPI_Comm_size(comm, &size));

5830:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
5831:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5832:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5833:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5835:   if (size == 1) {
5836:     startsj_s = NULL;
5837:     bufa_ptr  = NULL;
5838:     *B_oth    = NULL;
5839:     PetscFunctionReturn(PETSC_SUCCESS);
5840:   }

5842:   ctx = a->Mvctx;
5843:   tag = ((PetscObject)ctx)->tag;

5845:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5846:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5847:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5848:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5849:   PetscCall(PetscMalloc1(nreqs, &reqs));
5850:   rwaits = reqs;
5851:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5853:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5854:   if (scall == MAT_INITIAL_MATRIX) {
5855:     /* i-array */
5856:     /*  post receives */
5857:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5858:     for (i = 0; i < nrecvs; i++) {
5859:       rowlen = rvalues + rstarts[i] * rbs;
5860:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5861:       PetscCallMPI(MPIU_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5862:     }

5864:     /* pack the outgoing message */
5865:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5867:     sstartsj[0] = 0;
5868:     rstartsj[0] = 0;
5869:     len         = 0; /* total length of j or a array to be sent */
5870:     if (nsends) {
5871:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5872:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5873:     }
5874:     for (i = 0; i < nsends; i++) {
5875:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5876:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5877:       for (j = 0; j < nrows; j++) {
5878:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5879:         for (l = 0; l < sbs; l++) {
5880:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5882:           rowlen[j * sbs + l] = ncols;

5884:           len += ncols;
5885:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5886:         }
5887:         k++;
5888:       }
5889:       PetscCallMPI(MPIU_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5891:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5892:     }
5893:     /* recvs and sends of i-array are completed */
5894:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5895:     PetscCall(PetscFree(svalues));

5897:     /* allocate buffers for sending j and a arrays */
5898:     PetscCall(PetscMalloc1(len, &bufj));
5899:     if (!structure_only) PetscCall(PetscMalloc1(len, &bufa));

5901:     /* create i-array of B_oth */
5902:     PetscCall(PetscMalloc1(aBn + 1, &b_othi));

5904:     b_othi[0] = 0;
5905:     len       = 0; /* total length of j or a array to be received */
5906:     k         = 0;
5907:     for (i = 0; i < nrecvs; i++) {
5908:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5909:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5910:       for (j = 0; j < nrows; j++) {
5911:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5912:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5913:         k++;
5914:       }
5915:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5916:     }
5917:     PetscCall(PetscFree(rvalues));

5919:     /* allocate space for j and a arrays of B_oth */
5920:     PetscCall(PetscMalloc1(b_othi[aBn], &b_othj));
5921:     if (!structure_only) PetscCall(PetscMalloc1(b_othi[aBn], &b_otha));

5923:     /* j-array */
5924:     /*  post receives of j-array */
5925:     for (i = 0; i < nrecvs; i++) {
5926:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5927:       PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_othj, rstartsj[i]), nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5928:     }

5930:     /* pack the outgoing message j-array */
5931:     if (nsends) k = sstarts[0];
5932:     for (i = 0; i < nsends; i++) {
5933:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5934:       bufJ  = PetscSafePointerPlusOffset(bufj, sstartsj[i]);
5935:       for (j = 0; j < nrows; j++) {
5936:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5937:         for (ll = 0; ll < sbs; ll++) {
5938:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5939:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5940:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5941:         }
5942:       }
5943:       PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufj, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5944:     }

5946:     /* recvs and sends of j-array are completed */
5947:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5948:   } else if (scall == MAT_REUSE_MATRIX) {
5949:     sstartsj = *startsj_s;
5950:     rstartsj = *startsj_r;
5951:     bufa     = *bufa_ptr;
5952:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5953:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5955:   if (!structure_only) {
5956:     /* a-array */
5957:     /*  post receives of a-array */
5958:     for (i = 0; i < nrecvs; i++) {
5959:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5960:       PetscCallMPI(MPIU_Irecv(PetscSafePointerPlusOffset(b_otha, rstartsj[i]), nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
5961:     }

5963:     /* pack the outgoing message a-array */
5964:     if (nsends) k = sstarts[0];
5965:     for (i = 0; i < nsends; i++) {
5966:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5967:       bufA  = PetscSafePointerPlusOffset(bufa, sstartsj[i]);
5968:       for (j = 0; j < nrows; j++) {
5969:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5970:         for (ll = 0; ll < sbs; ll++) {
5971:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5972:           for (l = 0; l < ncols; l++) *bufA++ = vals[l];
5973:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
5974:         }
5975:       }
5976:       PetscCallMPI(MPIU_Isend(PetscSafePointerPlusOffset(bufa, sstartsj[i]), sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
5977:     }
5978:     /* recvs and sends of a-array are completed */
5979:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5980:   }
5981:   PetscCall(PetscFree(reqs));

5983:   if (scall == MAT_INITIAL_MATRIX) {
5984:     Mat_SeqAIJ *b_oth;

5986:     /* put together the new matrix */
5987:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));
5988:     PetscCall(MatSetOption(*B_oth, MAT_STRUCTURE_ONLY, structure_only));

5990:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5991:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5992:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
5993:     b_oth->free_a  = PETSC_TRUE;
5994:     b_oth->free_ij = PETSC_TRUE;
5995:     b_oth->nonew   = 0;

5997:     PetscCall(PetscFree(bufj));
5998:     if (!startsj_s || !bufa_ptr) {
5999:       PetscCall(PetscFree2(sstartsj, rstartsj));
6000:       PetscCall(PetscFree(bufa_ptr));
6001:     } else {
6002:       *startsj_s = sstartsj;
6003:       *startsj_r = rstartsj;
6004:       *bufa_ptr  = bufa;
6005:     }
6006:   } else if (scall == MAT_REUSE_MATRIX) {
6007:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
6008:   }

6010:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
6011:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
6012:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
6013:   PetscFunctionReturn(PETSC_SUCCESS);
6014: }

6016: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
6017: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
6018: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
6019: #if PetscDefined(HAVE_MKL_SPARSE)
6020: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
6021: #endif
6022: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
6023: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
6024: #if PetscDefined(HAVE_ELEMENTAL)
6025: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
6026: #endif
6027: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
6028: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
6029: #endif
6030: #if PetscDefined(HAVE_HYPRE)
6031: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
6032: #endif
6033: #if PetscDefined(HAVE_CUDA)
6034: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
6035: #endif
6036: #if PetscDefined(HAVE_HIP)
6037: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
6038: #endif
6039: #if PetscDefined(HAVE_KOKKOS_KERNELS)
6040: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6041: #endif
6042: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6043: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6044: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6046: /*
6047:     Computes (B'*A')' since computing B*A directly is untenable

6049:                n                       p                          p
6050:         [             ]       [             ]         [                 ]
6051:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6052:         [             ]       [             ]         [                 ]

6054: */
6055: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6056: {
6057:   Mat At, Bt, Ct;

6059:   PetscFunctionBegin;
6060:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6061:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6062:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_CURRENT, &Ct));
6063:   PetscCall(MatDestroy(&At));
6064:   PetscCall(MatDestroy(&Bt));
6065:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6066:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6067:   PetscCall(MatDestroy(&Ct));
6068:   PetscFunctionReturn(PETSC_SUCCESS);
6069: }

6071: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6072: {
6073:   PetscBool cisdense;

6075:   PetscFunctionBegin;
6076:   PetscCheck(A->cmap->n == B->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "A->cmap->n %" PetscInt_FMT " != B->rmap->n %" PetscInt_FMT, A->cmap->n, B->rmap->n);
6077:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6078:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6079:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6080:   if (!cisdense) {
6081:     PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6082:     PetscCall(MatSetVecType(C, A->defaultvectype));
6083:   }
6084:   PetscCall(MatSetUp(C));

6086:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6087:   PetscFunctionReturn(PETSC_SUCCESS);
6088: }

6090: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6091: {
6092:   Mat_Product *product = C->product;
6093:   Mat          A = product->A, B = product->B;

6095:   PetscFunctionBegin;
6096:   PetscCheck(A->cmap->rstart == B->rmap->rstart && A->cmap->rend == B->rmap->rend, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Matrix local dimensions are incompatible, (%" PetscInt_FMT ", %" PetscInt_FMT ") != (%" PetscInt_FMT ",%" PetscInt_FMT ")",
6097:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6098:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6099:   C->ops->productsymbolic = MatProductSymbolic_AB;
6100:   PetscFunctionReturn(PETSC_SUCCESS);
6101: }

6103: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6104: {
6105:   Mat_Product *product = C->product;

6107:   PetscFunctionBegin;
6108:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6109:   PetscFunctionReturn(PETSC_SUCCESS);
6110: }

6112: /*
6113:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6115:   Input Parameters:

6117:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6118:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6120:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6122:     For Set1, j1[] contains column indices of the nonzeros.
6123:     For the k-th row (0<=k<m), [rowBegin1[k],rowEnd1[k]) index into j1[] and point to the begin/end nonzero in row k
6124:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6125:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6127:     Similar for Set2.

6129:     This routine merges the two sets of nonzeros row by row and removes repeats.

6131:   Output Parameters: (memory is allocated by the caller)

6133:     i[],j[]: the CSR of the merged matrix, which has m rows.
6134:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6135:     imap2[]: similar to imap1[], but for Set2.
6136:     Note we order nonzeros row-by-row and from left to right.
6137: */
6138: static PetscErrorCode MatMergeEntries_Internal(Mat mat, const PetscInt j1[], const PetscInt j2[], const PetscCount rowBegin1[], const PetscCount rowEnd1[], const PetscCount rowBegin2[], const PetscCount rowEnd2[], const PetscCount jmap1[], const PetscCount jmap2[], PetscCount imap1[], PetscCount imap2[], PetscInt i[], PetscInt j[])
6139: {
6140:   PetscInt   r, m; /* Row index of mat */
6141:   PetscCount t, t1, t2, b1, e1, b2, e2;

6143:   PetscFunctionBegin;
6144:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6145:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6146:   i[0]        = 0;
6147:   for (r = 0; r < m; r++) { /* Do row by row merging */
6148:     b1 = rowBegin1[r];
6149:     e1 = rowEnd1[r];
6150:     b2 = rowBegin2[r];
6151:     e2 = rowEnd2[r];
6152:     while (b1 < e1 && b2 < e2) {
6153:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6154:         j[t]      = j1[b1];
6155:         imap1[t1] = t;
6156:         imap2[t2] = t;
6157:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6158:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6159:         t1++;
6160:         t2++;
6161:         t++;
6162:       } else if (j1[b1] < j2[b2]) {
6163:         j[t]      = j1[b1];
6164:         imap1[t1] = t;
6165:         b1 += jmap1[t1 + 1] - jmap1[t1];
6166:         t1++;
6167:         t++;
6168:       } else {
6169:         j[t]      = j2[b2];
6170:         imap2[t2] = t;
6171:         b2 += jmap2[t2 + 1] - jmap2[t2];
6172:         t2++;
6173:         t++;
6174:       }
6175:     }
6176:     /* Merge the remaining in either j1[] or j2[] */
6177:     while (b1 < e1) {
6178:       j[t]      = j1[b1];
6179:       imap1[t1] = t;
6180:       b1 += jmap1[t1 + 1] - jmap1[t1];
6181:       t1++;
6182:       t++;
6183:     }
6184:     while (b2 < e2) {
6185:       j[t]      = j2[b2];
6186:       imap2[t2] = t;
6187:       b2 += jmap2[t2 + 1] - jmap2[t2];
6188:       t2++;
6189:       t++;
6190:     }
6191:     PetscCall(PetscIntCast(t, i + r + 1));
6192:   }
6193:   PetscFunctionReturn(PETSC_SUCCESS);
6194: }

6196: /*
6197:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6199:   Input Parameters:
6200:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6201:     n,i[],j[],perm[]: there are n input entries, belonging to m rows. Row/col indices of the entries are stored in i[] and j[]
6202:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6204:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6205:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6207:   Output Parameters:
6208:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6209:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6210:       They contain indices pointing to j[]. For 0<=r<m, [rowBegin[r],rowMid[r]) point to begin/end entries of row r of the diagonal block,
6211:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6213:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6214:       Atot: number of entries belonging to the diagonal block.
6215:       Annz: number of unique nonzeros belonging to the diagonal block.
6216:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6217:         repeats (i.e., same 'i,j' pair).
6218:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6219:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6221:       Atot: number of entries belonging to the diagonal block
6222:       Annz: number of unique nonzeros belonging to the diagonal block.

6224:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6226:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6227: */
6228: static PetscErrorCode MatSplitEntries_Internal(Mat mat, PetscCount n, const PetscInt i[], PetscInt j[], PetscCount perm[], PetscCount rowBegin[], PetscCount rowMid[], PetscCount rowEnd[], PetscCount *Atot_, PetscCount **Aperm_, PetscCount *Annz_, PetscCount **Ajmap_, PetscCount *Btot_, PetscCount **Bperm_, PetscCount *Bnnz_, PetscCount **Bjmap_)
6229: {
6230:   PetscInt    cstart, cend, rstart, rend, row, col;
6231:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6232:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6233:   PetscCount  k, m, p, q, r, s, mid;
6234:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6236:   PetscFunctionBegin;
6237:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6238:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6239:   m = rend - rstart;

6241:   /* Skip negative rows */
6242:   for (k = 0; k < n; k++)
6243:     if (i[k] >= 0) break;

6245:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6246:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6247:   */
6248:   while (k < n) {
6249:     row = i[k];
6250:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6251:     for (s = k; s < n; s++)
6252:       if (i[s] != row) break;

6254:     /* Shift diag columns to range of [-PETSC_INT_MAX, -1] */
6255:     for (p = k; p < s; p++) {
6256:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_INT_MAX;
6257:     }
6258:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6259:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6260:     rowBegin[row - rstart] = k;
6261:     rowMid[row - rstart]   = mid;
6262:     rowEnd[row - rstart]   = s;
6263:     PetscCheck(k == s || j[s - 1] < mat->cmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column index %" PetscInt_FMT " is >= matrix column size %" PetscInt_FMT, j[s - 1], mat->cmap->N);

6265:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6266:     Atot += mid - k;
6267:     Btot += s - mid;

6269:     /* Count unique nonzeros of this diag row */
6270:     for (p = k; p < mid;) {
6271:       col = j[p];
6272:       do {
6273:         j[p] += PETSC_INT_MAX; /* Revert the modified diagonal indices */
6274:         p++;
6275:       } while (p < mid && j[p] == col);
6276:       Annz++;
6277:     }

6279:     /* Count unique nonzeros of this offdiag row */
6280:     for (p = mid; p < s;) {
6281:       col = j[p];
6282:       do {
6283:         p++;
6284:       } while (p < s && j[p] == col);
6285:       Bnnz++;
6286:     }
6287:     k = s;
6288:   }

6290:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6291:   PetscCall(PetscMalloc1(Atot, &Aperm));
6292:   PetscCall(PetscMalloc1(Btot, &Bperm));
6293:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6294:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6296:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6297:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6298:   for (r = 0; r < m; r++) {
6299:     k   = rowBegin[r];
6300:     mid = rowMid[r];
6301:     s   = rowEnd[r];
6302:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6303:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6304:     Atot += mid - k;
6305:     Btot += s - mid;

6307:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6308:     for (p = k; p < mid;) {
6309:       col = j[p];
6310:       q   = p;
6311:       do {
6312:         p++;
6313:       } while (p < mid && j[p] == col);
6314:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6315:       Annz++;
6316:     }

6318:     for (p = mid; p < s;) {
6319:       col = j[p];
6320:       q   = p;
6321:       do {
6322:         p++;
6323:       } while (p < s && j[p] == col);
6324:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6325:       Bnnz++;
6326:     }
6327:   }
6328:   /* Output */
6329:   *Aperm_ = Aperm;
6330:   *Annz_  = Annz;
6331:   *Atot_  = Atot;
6332:   *Ajmap_ = Ajmap;
6333:   *Bperm_ = Bperm;
6334:   *Bnnz_  = Bnnz;
6335:   *Btot_  = Btot;
6336:   *Bjmap_ = Bjmap;
6337:   PetscFunctionReturn(PETSC_SUCCESS);
6338: }

6340: /*
6341:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6343:   Input Parameters:
6344:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6345:     nnz:  number of unique nonzeros in the merged matrix
6346:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6347:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6349:   Output Parameter: (memory is allocated by the caller)
6350:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6352:   Example:
6353:     nnz1 = 4
6354:     nnz  = 6
6355:     imap = [1,3,4,5]
6356:     jmap = [0,3,5,6,7]
6357:    then,
6358:     jmap_new = [0,0,3,3,5,6,7]
6359: */
6360: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6361: {
6362:   PetscCount k, p;

6364:   PetscFunctionBegin;
6365:   jmap_new[0] = 0;
6366:   p           = nnz;                /* p loops over jmap_new[] backwards */
6367:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6368:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6369:   }
6370:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6371:   PetscFunctionReturn(PETSC_SUCCESS);
6372: }

6374: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(PetscCtxRt data)
6375: {
6376:   MatCOOStruct_MPIAIJ *coo = *(MatCOOStruct_MPIAIJ **)data;

6378:   PetscFunctionBegin;
6379:   PetscCall(PetscSFDestroy(&coo->sf));
6380:   PetscCall(PetscFree(coo->Aperm1));
6381:   PetscCall(PetscFree(coo->Bperm1));
6382:   PetscCall(PetscFree(coo->Ajmap1));
6383:   PetscCall(PetscFree(coo->Bjmap1));
6384:   PetscCall(PetscFree(coo->Aimap2));
6385:   PetscCall(PetscFree(coo->Bimap2));
6386:   PetscCall(PetscFree(coo->Aperm2));
6387:   PetscCall(PetscFree(coo->Bperm2));
6388:   PetscCall(PetscFree(coo->Ajmap2));
6389:   PetscCall(PetscFree(coo->Bjmap2));
6390:   PetscCall(PetscFree(coo->Cperm1));
6391:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6392:   PetscCall(PetscFree(coo));
6393:   PetscFunctionReturn(PETSC_SUCCESS);
6394: }

6396: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6397: {
6398:   MPI_Comm             comm;
6399:   PetscMPIInt          rank, size;
6400:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6401:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6402:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6403:   PetscContainer       container;
6404:   MatCOOStruct_MPIAIJ *coo;

6406:   PetscFunctionBegin;
6407:   PetscCall(PetscFree(mpiaij->garray));
6408:   PetscCall(VecDestroy(&mpiaij->lvec));
6409: #if PetscDefined(USE_CTABLE)
6410:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6411: #else
6412:   PetscCall(PetscFree(mpiaij->colmap));
6413: #endif
6414:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6415:   mat->assembled     = PETSC_FALSE;
6416:   mat->was_assembled = PETSC_FALSE;

6418:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6419:   PetscCallMPI(MPI_Comm_size(comm, &size));
6420:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6421:   PetscCall(PetscLayoutSetUp(mat->rmap));
6422:   PetscCall(PetscLayoutSetUp(mat->cmap));
6423:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6424:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6425:   PetscCall(MatGetLocalSize(mat, &m, &n));
6426:   PetscCall(MatGetSize(mat, &M, &N));

6428:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6429:   /* entries come first, then local rows, then remote rows.                     */
6430:   PetscCount n1 = coo_n, *perm1;
6431:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6433:   PetscCall(PetscMalloc1(n1, &perm1));
6434:   for (k = 0; k < n1; k++) perm1[k] = k;

6436:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6437:      row indices, local entries will have greater but negative row indices, and remote entries
6438:      will have positive row indices.
6439:   */
6440:   for (k = 0; k < n1; k++) {
6441:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_INT_MIN;                /* e.g., -2^31, minimal to move them ahead */
6442:     else if (i1[k] >= rstart && i1[k] < rend) i1[k] -= PETSC_INT_MAX; /* e.g., minus 2^31-1 to shift local rows to range of [-PETSC_INT_MAX, -1] */
6443:     else {
6444:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6445:       if (mpiaij->donotstash) i1[k] = PETSC_INT_MIN; /* Ignore offproc entries as if they had negative indices */
6446:     }
6447:   }

6449:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6450:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6452:   /* Advance k to the first entry we need to take care of */
6453:   for (k = 0; k < n1; k++)
6454:     if (i1[k] > PETSC_INT_MIN) break;
6455:   PetscCount i1start = k;

6457:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_INT_MAX, &rem)); /* rem is upper bound of the last local row */
6458:   for (; k < rem; k++) i1[k] += PETSC_INT_MAX;                                    /* Revert row indices of local rows*/

6460:   PetscCheck(n1 == 0 || i1[n1 - 1] < M, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "COO row index %" PetscInt_FMT " is >= the matrix row size %" PetscInt_FMT, i1[n1 - 1], M);

6462:   /*           Send remote rows to their owner                                  */
6463:   /* Find which rows should be sent to which remote ranks*/
6464:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6465:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6466:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6467:   const PetscInt *ranges;
6468:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6470:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6471:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6472:   for (k = rem; k < n1;) {
6473:     PetscMPIInt owner;
6474:     PetscInt    firstRow, lastRow;

6476:     /* Locate a row range */
6477:     firstRow = i1[k]; /* first row of this owner */
6478:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6479:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6481:     /* Find the first index 'p' in [k,n) with i1[p] belonging to next owner */
6482:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6484:     /* All entries in [k,p) belong to this remote owner */
6485:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6486:       PetscMPIInt *sendto2;
6487:       PetscInt    *nentries2;
6488:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6490:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6491:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6492:       PetscCall(PetscArraycpy(nentries2, nentries, maxNsend));
6493:       PetscCall(PetscFree2(sendto, nentries));
6494:       sendto   = sendto2;
6495:       nentries = nentries2;
6496:       maxNsend = maxNsend2;
6497:     }
6498:     sendto[nsend] = owner;
6499:     PetscCall(PetscIntCast(p - k, &nentries[nsend]));
6500:     nsend++;
6501:     k = p;
6502:   }

6504:   /* Build 1st SF to know offsets on remote to send data */
6505:   PetscSF      sf1;
6506:   PetscInt     nroots = 1, nroots2 = 0;
6507:   PetscInt     nleaves = nsend, nleaves2 = 0;
6508:   PetscInt    *offsets;
6509:   PetscSFNode *iremote;

6511:   PetscCall(PetscSFCreate(comm, &sf1));
6512:   PetscCall(PetscMalloc1(nsend, &iremote));
6513:   PetscCall(PetscMalloc1(nsend, &offsets));
6514:   for (k = 0; k < nsend; k++) {
6515:     iremote[k].rank  = sendto[k];
6516:     iremote[k].index = 0;
6517:     nleaves2 += nentries[k];
6518:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6519:   }
6520:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6521:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6522:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6523:   PetscCall(PetscSFDestroy(&sf1));
6524:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6526:   /* Build 2nd SF to send remote COOs to their owner */
6527:   PetscSF sf2;
6528:   nroots  = nroots2;
6529:   nleaves = nleaves2;
6530:   PetscCall(PetscSFCreate(comm, &sf2));
6531:   PetscCall(PetscSFSetFromOptions(sf2));
6532:   PetscCall(PetscMalloc1(nleaves, &iremote));
6533:   p = 0;
6534:   for (k = 0; k < nsend; k++) {
6535:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6536:     for (q = 0; q < nentries[k]; q++, p++) {
6537:       iremote[p].rank = sendto[k];
6538:       PetscCall(PetscIntCast(offsets[k] + q, &iremote[p].index));
6539:     }
6540:   }
6541:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6543:   /* Send the remote COOs to their owner */
6544:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6545:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6546:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6547:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6548:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6549:   PetscInt *i1prem = PetscSafePointerPlusOffset(i1, rem);
6550:   PetscInt *j1prem = PetscSafePointerPlusOffset(j1, rem);
6551:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6552:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6553:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6554:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6556:   PetscCall(PetscFree(offsets));
6557:   PetscCall(PetscFree2(sendto, nentries));

6559:   /* Sort received COOs by row along with the permutation array     */
6560:   for (k = 0; k < n2; k++) perm2[k] = k;
6561:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6563:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6564:   PetscCount *Cperm1;
6565:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6566:   PetscCount *perm1prem = PetscSafePointerPlusOffset(perm1, rem);
6567:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6568:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6570:   /* Support for HYPRE matrices, kind of a hack.
6571:      Swap min column with diagonal so that diagonal values will go first */
6572:   PetscBool hypre;
6573:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", ((PetscObject)mat)->name, &hypre));
6574:   if (hypre) {
6575:     PetscInt *minj;
6576:     PetscBT   hasdiag;

6578:     PetscCall(PetscBTCreate(m, &hasdiag));
6579:     PetscCall(PetscMalloc1(m, &minj));
6580:     for (k = 0; k < m; k++) minj[k] = PETSC_INT_MAX;
6581:     for (k = i1start; k < rem; k++) {
6582:       if (j1[k] < cstart || j1[k] >= cend) continue;
6583:       const PetscInt rindex = i1[k] - rstart;
6584:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6585:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6586:     }
6587:     for (k = 0; k < n2; k++) {
6588:       if (j2[k] < cstart || j2[k] >= cend) continue;
6589:       const PetscInt rindex = i2[k] - rstart;
6590:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6591:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6592:     }
6593:     for (k = i1start; k < rem; k++) {
6594:       const PetscInt rindex = i1[k] - rstart;
6595:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6596:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6597:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6598:     }
6599:     for (k = 0; k < n2; k++) {
6600:       const PetscInt rindex = i2[k] - rstart;
6601:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6602:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6603:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6604:     }
6605:     PetscCall(PetscBTDestroy(&hasdiag));
6606:     PetscCall(PetscFree(minj));
6607:   }

6609:   /* Split local COOs and received COOs into diag/offdiag portions */
6610:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6611:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6612:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6613:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6614:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6615:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6617:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6618:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6619:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6620:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6622:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6623:   PetscInt *Ai, *Bi;
6624:   PetscInt *Aj, *Bj;

6626:   PetscCall(PetscMalloc1(m + 1, &Ai));
6627:   PetscCall(PetscMalloc1(m + 1, &Bi));
6628:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6629:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6631:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6632:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6633:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6634:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6635:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6637:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6638:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6640:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6641:   /* expect nonzeros in A/B most likely have local contributing entries        */
6642:   PetscInt    Annz = Ai[m];
6643:   PetscInt    Bnnz = Bi[m];
6644:   PetscCount *Ajmap1_new, *Bjmap1_new;

6646:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6647:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6649:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6650:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6652:   PetscCall(PetscFree(Aimap1));
6653:   PetscCall(PetscFree(Ajmap1));
6654:   PetscCall(PetscFree(Bimap1));
6655:   PetscCall(PetscFree(Bjmap1));
6656:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6657:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6658:   PetscCall(PetscFree(perm1));
6659:   PetscCall(PetscFree3(i2, j2, perm2));

6661:   Ajmap1 = Ajmap1_new;
6662:   Bjmap1 = Bjmap1_new;

6664:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6665:   if (Annz < Annz1 + Annz2) {
6666:     PetscInt *Aj_new;
6667:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6668:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6669:     PetscCall(PetscFree(Aj));
6670:     Aj = Aj_new;
6671:   }

6673:   if (Bnnz < Bnnz1 + Bnnz2) {
6674:     PetscInt *Bj_new;
6675:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6676:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6677:     PetscCall(PetscFree(Bj));
6678:     Bj = Bj_new;
6679:   }

6681:   /* Create new submatrices for on-process and off-process coupling                  */
6682:   PetscScalar *Aa = NULL, *Ba = NULL;
6683:   MatType      rtype;
6684:   Mat_SeqAIJ  *a, *b;
6685:   if (!mat->structure_only) {
6686:     PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6687:     PetscCall(PetscCalloc1(Bnnz, &Ba));
6688:   }
6689:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6690:   if (cstart) {
6691:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6692:   }

6694:   PetscCall(MatGetRootType_Private(mat, &rtype));

6696:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6697:   PetscCall(MatDestroy(&mpiaij->A));
6698:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6699:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6700:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);
6701:   PetscCall(MatSetOption(mpiaij->A, MAT_STRUCTURE_ONLY, mat->structure_only));

6703:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6704:   PetscCall(MatDestroy(&mpiaij->B));
6705:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6706:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6707:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);
6708:   PetscCall(MatSetOption(mpiaij->B, MAT_STRUCTURE_ONLY, mat->structure_only));

6710:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6711:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6712:   mat->nonzerostate  = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6713:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6715:   a          = (Mat_SeqAIJ *)mpiaij->A->data;
6716:   b          = (Mat_SeqAIJ *)mpiaij->B->data;
6717:   a->free_a  = (PetscBool)!mat->structure_only;
6718:   a->free_ij = PETSC_TRUE;
6719:   b->free_a  = (PetscBool)!mat->structure_only;
6720:   b->free_ij = PETSC_TRUE;
6721:   a->maxnz   = a->nz;
6722:   b->maxnz   = b->nz;

6724:   /* conversion must happen AFTER multiply setup */
6725:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6726:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6727:   PetscCall(VecDestroy(&mpiaij->lvec));
6728:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6730:   // Put the COO struct in a container and then attach that to the matrix
6731:   PetscCall(PetscMalloc1(1, &coo));
6732:   coo->n       = coo_n;
6733:   coo->sf      = sf2;
6734:   coo->sendlen = nleaves;
6735:   coo->recvlen = nroots;
6736:   coo->Annz    = Annz;
6737:   coo->Bnnz    = Bnnz;
6738:   coo->Annz2   = Annz2;
6739:   coo->Bnnz2   = Bnnz2;
6740:   coo->Atot1   = Atot1;
6741:   coo->Atot2   = Atot2;
6742:   coo->Btot1   = Btot1;
6743:   coo->Btot2   = Btot2;
6744:   coo->Ajmap1  = Ajmap1;
6745:   coo->Aperm1  = Aperm1;
6746:   coo->Bjmap1  = Bjmap1;
6747:   coo->Bperm1  = Bperm1;
6748:   coo->Aimap2  = Aimap2;
6749:   coo->Ajmap2  = Ajmap2;
6750:   coo->Aperm2  = Aperm2;
6751:   coo->Bimap2  = Bimap2;
6752:   coo->Bjmap2  = Bjmap2;
6753:   coo->Bperm2  = Bperm2;
6754:   coo->Cperm1  = Cperm1;
6755:   // Allocate in preallocation. If not used, it has zero cost on host
6756:   if (!mat->structure_only) PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6757:   else coo->sendbuf = coo->recvbuf = NULL;
6758:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6759:   PetscCall(PetscContainerSetPointer(container, coo));
6760:   PetscCall(PetscContainerSetCtxDestroy(container, MatCOOStructDestroy_MPIAIJ));
6761:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6762:   PetscCall(PetscContainerDestroy(&container));
6763:   PetscFunctionReturn(PETSC_SUCCESS);
6764: }

6766: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6767: {
6768:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6769:   Mat                  A = mpiaij->A, B = mpiaij->B;
6770:   PetscScalar         *Aa, *Ba;
6771:   PetscScalar         *sendbuf, *recvbuf;
6772:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6773:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6774:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6775:   const PetscCount    *Cperm1;
6776:   PetscContainer       container;
6777:   MatCOOStruct_MPIAIJ *coo;

6779:   PetscFunctionBegin;
6780:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6781:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6782:   PetscCall(PetscContainerGetPointer(container, &coo));
6783:   sendbuf = coo->sendbuf;
6784:   recvbuf = coo->recvbuf;
6785:   Ajmap1  = coo->Ajmap1;
6786:   Ajmap2  = coo->Ajmap2;
6787:   Aimap2  = coo->Aimap2;
6788:   Bjmap1  = coo->Bjmap1;
6789:   Bjmap2  = coo->Bjmap2;
6790:   Bimap2  = coo->Bimap2;
6791:   Aperm1  = coo->Aperm1;
6792:   Aperm2  = coo->Aperm2;
6793:   Bperm1  = coo->Bperm1;
6794:   Bperm2  = coo->Bperm2;
6795:   Cperm1  = coo->Cperm1;

6797:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6798:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6800:   /* Pack entries to be sent to remote */
6801:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6803:   /* Send remote entries to their owner and overlap the communication with local computation */
6804:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6805:   /* Add local entries to A and B */
6806:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6807:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6808:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6809:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6810:   }
6811:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6812:     PetscScalar sum = 0.0;
6813:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6814:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6815:   }
6816:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6818:   /* Add received remote entries to A and B */
6819:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6820:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6821:   }
6822:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6823:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6824:   }
6825:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6826:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6827:   PetscFunctionReturn(PETSC_SUCCESS);
6828: }

6830: /*MC
6831:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6833:    Options Database Keys:
6834: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6836:    Level: beginner

6838:    Notes:
6839:    `MatSetValues()` may be called with a `NULL` argument for the numerical values to insert zeros at the supplied row and column indices.

6841:     Call `MatSetOption(A, MAT_STRUCTURE_ONLY, PETSC_TRUE)` before preallocation or `MatSetUp()` to store only the nonzero pattern.
6842:     The assembled matrix has no numerical value array. Row and column indices supplied during insertion are retained, while numerical values are ignored.
6843:     Such matrices can be used for structural operations, but not for numerical operations.

6845: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6846: M*/
6847: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6848: {
6849:   Mat_MPIAIJ *b;
6850:   PetscMPIInt size;

6852:   PetscFunctionBegin;
6853:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6855:   PetscCall(PetscNew(&b));
6856:   B->data       = (void *)b;
6857:   B->ops[0]     = MatOps_Values;
6858:   B->assembled  = PETSC_FALSE;
6859:   B->insertmode = NOT_SET_VALUES;
6860:   b->size       = size;

6862:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6864:   /* build cache for off array entries formed */
6865:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6867:   b->donotstash  = PETSC_FALSE;
6868:   b->colmap      = NULL;
6869:   b->garray      = NULL;
6870:   b->roworiented = PETSC_TRUE;

6872:   /* stuff used for matrix vector multiply */
6873:   b->lvec  = NULL;
6874:   b->Mvctx = NULL;

6876:   /* stuff for MatGetRow() */
6877:   b->rowindices   = NULL;
6878:   b->rowvalues    = NULL;
6879:   b->getrowactive = PETSC_FALSE;

6881:   /* flexible pointer used in CUSPARSE classes */
6882:   b->spptr = NULL;

6884:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6885:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6886:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6887:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6888:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6889:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6890:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetHash_C", MatResetHash_MPIAIJ));
6891:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6892:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6893:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6894:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6895: #if PetscDefined(HAVE_CUDA)
6896:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6897: #endif
6898: #if PetscDefined(HAVE_HIP)
6899:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6900: #endif
6901: #if PetscDefined(HAVE_KOKKOS_KERNELS)
6902:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6903: #endif
6904: #if PetscDefined(HAVE_MKL_SPARSE)
6905:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6906: #endif
6907:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6908:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6909:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6910:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6911: #if PetscDefined(HAVE_ELEMENTAL)
6912:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6913: #endif
6914: #if PetscDefined(HAVE_SCALAPACK) && (PetscDefined(USE_REAL_SINGLE) || PetscDefined(USE_REAL_DOUBLE))
6915:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6916: #endif
6917:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6918:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6919: #if PetscDefined(HAVE_HYPRE)
6920:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6921:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6922: #endif
6923:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6924:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6925:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6926:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6927:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatGetMultPetscSF_C", MatGetMultPetscSF_MPIAIJ));
6928:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6929:   PetscFunctionReturn(PETSC_SUCCESS);
6930: }

6932: /*@
6933:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6934:   and "off-diagonal" part of the matrix in CSR format.

6936:   Collective

6938:   Input Parameters:
6939: + comm - MPI communicator
6940: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6941: . n    - This value should be the same as the local size used in creating the
6942:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6943:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6944: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6945: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6946: . i    - row indices for "diagonal" portion of matrix; that is i[0] = 0, i[row] = i[row-1] + number of elements in that row of the matrix
6947: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6948: . a    - matrix values
6949: . oi   - row indices for "off-diagonal" portion of matrix; that is oi[0] = 0, oi[row] = oi[row-1] + number of elements in that row of the matrix
6950: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6951: - oa   - matrix values

6953:   Output Parameter:
6954: . mat - the matrix

6956:   Level: advanced

6958:   Notes:
6959:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6960:   must free the arrays once the matrix has been destroyed and not before.

6962:   The `i` and `j` indices are 0 based

6964:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6966:   This sets local rows and cannot be used to set off-processor values.

6968:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6969:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6970:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
6971:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
6972:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
6973:   communication if it is known that only local entries will be set.

6975: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
6976:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
6977: @*/
6978: PetscErrorCode MatCreateMPIAIJWithSplitArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt i[], PetscInt j[], PetscScalar a[], PetscInt oi[], PetscInt oj[], PetscScalar oa[], Mat *mat)
6979: {
6980:   Mat_MPIAIJ *maij;

6982:   PetscFunctionBegin;
6983:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
6984:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
6985:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
6986:   PetscCall(MatCreate(comm, mat));
6987:   PetscCall(MatSetSizes(*mat, m, n, M, N));
6988:   PetscCall(MatSetType(*mat, MATMPIAIJ));
6989:   maij = (Mat_MPIAIJ *)(*mat)->data;

6991:   (*mat)->preallocated = PETSC_TRUE;

6993:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
6994:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

6996:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
6997:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

6999:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
7000:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
7001:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
7002:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
7003:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
7004:   PetscFunctionReturn(PETSC_SUCCESS);
7005: }

7007: typedef struct {
7008:   Mat       *mp;    /* intermediate products */
7009:   PetscBool *mptmp; /* is the intermediate product temporary ? */
7010:   PetscInt   cp;    /* number of intermediate products */

7012:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
7013:   PetscInt    *startsj_s, *startsj_r;
7014:   PetscScalar *bufa;
7015:   Mat          P_oth;

7017:   /* may take advantage of merging product->B */
7018:   Mat Bloc; /* B-local by merging diag and off-diag */

7020:   /* cusparse does not have support to split between symbolic and numeric phases.
7021:      When api_user is true, we don't need to update the numerical values
7022:      of the temporary storage */
7023:   PetscBool reusesym;

7025:   /* support for COO values insertion */
7026:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
7027:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
7028:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
7029:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
7030:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
7031:   PetscMemType mtype;

7033:   /* customization */
7034:   PetscBool abmerge;
7035:   PetscBool P_oth_bind;
7036: } MatMatMPIAIJBACKEND;

7038: static PetscErrorCode MatProductCtxDestroy_MatMatMPIAIJBACKEND(PetscCtxRt data)
7039: {
7040:   MatMatMPIAIJBACKEND *mmdata = *(MatMatMPIAIJBACKEND **)data;
7041:   PetscInt             i;

7043:   PetscFunctionBegin;
7044:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
7045:   PetscCall(PetscFree(mmdata->bufa));
7046:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
7047:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
7048:   PetscCall(MatDestroy(&mmdata->P_oth));
7049:   PetscCall(MatDestroy(&mmdata->Bloc));
7050:   PetscCall(PetscSFDestroy(&mmdata->sf));
7051:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7052:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7053:   PetscCall(PetscFree(mmdata->own[0]));
7054:   PetscCall(PetscFree(mmdata->own));
7055:   PetscCall(PetscFree(mmdata->off[0]));
7056:   PetscCall(PetscFree(mmdata->off));
7057:   PetscCall(PetscFree(mmdata));
7058:   PetscFunctionReturn(PETSC_SUCCESS);
7059: }

7061: /* Copy selected n entries with indices in idx[] of A to v[].
7062:    If idx is NULL, copy the whole data array of A to v[]
7063:  */
7064: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7065: {
7066:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7068:   PetscFunctionBegin;
7069:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7070:   if (f) PetscCall((*f)(A, n, idx, v));
7071:   else {
7072:     const PetscScalar *vv;

7074:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7075:     if (n && idx) {
7076:       PetscScalar    *w  = v;
7077:       const PetscInt *oi = idx;

7079:       for (PetscInt j = 0; j < n; j++) *w++ = vv[*oi++];
7080:     } else {
7081:       PetscCall(PetscArraycpy(v, vv, n));
7082:     }
7083:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7084:   }
7085:   PetscFunctionReturn(PETSC_SUCCESS);
7086: }

7088: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7089: {
7090:   MatMatMPIAIJBACKEND *mmdata;
7091:   PetscInt             i, n_d, n_o;

7093:   PetscFunctionBegin;
7094:   MatCheckProduct(C, 1);
7095:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7096:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7097:   if (!mmdata->reusesym) { /* update temporary matrices */
7098:     if (mmdata->P_oth) PetscCall(MatGetBrowsOfAoCols_MPIAIJ(C->product->A, C->product->B, MAT_REUSE_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7099:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7100:   }
7101:   mmdata->reusesym = PETSC_FALSE;

7103:   for (i = 0; i < mmdata->cp; i++) {
7104:     PetscCheck(mmdata->mp[i]->ops->productnumeric, PetscObjectComm((PetscObject)mmdata->mp[i]), PETSC_ERR_PLIB, "Missing numeric op for %s", MatProductTypes[mmdata->mp[i]->product->type]);
7105:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7106:   }
7107:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7108:     PetscInt noff;

7110:     PetscCall(PetscIntCast(mmdata->off[i + 1] - mmdata->off[i], &noff));
7111:     if (mmdata->mptmp[i]) continue;
7112:     if (noff) {
7113:       PetscInt nown;

7115:       PetscCall(PetscIntCast(mmdata->own[i + 1] - mmdata->own[i], &nown));
7116:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7117:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7118:       n_o += noff;
7119:       n_d += nown;
7120:     } else {
7121:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7123:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7124:       n_d += mm->nz;
7125:     }
7126:   }
7127:   if (mmdata->hasoffproc) { /* offprocess insertion */
7128:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7129:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7130:   }
7131:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7132:   PetscFunctionReturn(PETSC_SUCCESS);
7133: }

7135: /* Support for Pt * A, A * P, or Pt * A * P */
7136: #define MAX_NUMBER_INTERMEDIATE 4
7137: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7138: {
7139:   Mat_Product           *product = C->product;
7140:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7141:   Mat_MPIAIJ            *a, *p;
7142:   MatMatMPIAIJBACKEND   *mmdata;
7143:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7144:   IS                     glob      = NULL;
7145:   const char            *prefix;
7146:   char                   pprefix[256];
7147:   const PetscInt        *globidx, *P_oth_idx;
7148:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7149:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7150:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7151:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7152:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7153:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7155:   MatProductType ptype;
7156:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7157:   PetscMPIInt    size;

7159:   PetscFunctionBegin;
7160:   MatCheckProduct(C, 1);
7161:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7162:   ptype = product->type;
7163:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7164:     ptype                                          = MATPRODUCT_AB;
7165:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7166:   }
7167:   switch (ptype) {
7168:   case MATPRODUCT_AB:
7169:     A          = product->A;
7170:     P          = product->B;
7171:     m          = A->rmap->n;
7172:     n          = P->cmap->n;
7173:     M          = A->rmap->N;
7174:     N          = P->cmap->N;
7175:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7176:     break;
7177:   case MATPRODUCT_AtB:
7178:     P          = product->A;
7179:     A          = product->B;
7180:     m          = P->cmap->n;
7181:     n          = A->cmap->n;
7182:     M          = P->cmap->N;
7183:     N          = A->cmap->N;
7184:     hasoffproc = PETSC_TRUE;
7185:     break;
7186:   case MATPRODUCT_PtAP:
7187:     A          = product->A;
7188:     P          = product->B;
7189:     m          = P->cmap->n;
7190:     n          = P->cmap->n;
7191:     M          = P->cmap->N;
7192:     N          = P->cmap->N;
7193:     hasoffproc = PETSC_TRUE;
7194:     break;
7195:   default:
7196:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7197:   }
7198:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7199:   if (size == 1) hasoffproc = PETSC_FALSE;

7201:   /* defaults */
7202:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7203:     mp[i]    = NULL;
7204:     mptmp[i] = PETSC_FALSE;
7205:     rmapt[i] = -1;
7206:     cmapt[i] = -1;
7207:     rmapa[i] = NULL;
7208:     cmapa[i] = NULL;
7209:   }

7211:   /* customization */
7212:   PetscCall(PetscNew(&mmdata));
7213:   mmdata->reusesym = product->api_user;
7214:   if (ptype == MATPRODUCT_AB) {
7215:     if (product->api_user) {
7216:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7217:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7218:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7219:       PetscOptionsEnd();
7220:     } else {
7221:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7222:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7223:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7224:       PetscOptionsEnd();
7225:     }
7226:   } else if (ptype == MATPRODUCT_PtAP) {
7227:     if (product->api_user) {
7228:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7229:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7230:       PetscOptionsEnd();
7231:     } else {
7232:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7233:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7234:       PetscOptionsEnd();
7235:     }
7236:   }
7237:   a = (Mat_MPIAIJ *)A->data;
7238:   p = (Mat_MPIAIJ *)P->data;
7239:   PetscCall(MatSetSizes(C, m, n, M, N));
7240:   PetscCall(PetscLayoutSetUp(C->rmap));
7241:   PetscCall(PetscLayoutSetUp(C->cmap));
7242:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7243:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7245:   cp = 0;
7246:   switch (ptype) {
7247:   case MATPRODUCT_AB: /* A * P */
7248:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7250:     /* A_diag * P_local (merged or not) */
7251:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7252:       /* P is product->B */
7253:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7254:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7255:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7256:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7257:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7258:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7259:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7260:       mp[cp]->product->api_user = product->api_user;
7261:       PetscCall(MatProductSetFromOptions(mp[cp]));
7262:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7263:       PetscCall(ISGetIndices(glob, &globidx));
7264:       rmapt[cp] = 1;
7265:       cmapt[cp] = 2;
7266:       cmapa[cp] = globidx;
7267:       mptmp[cp] = PETSC_FALSE;
7268:       cp++;
7269:     } else { /* A_diag * P_diag and A_diag * P_off */
7270:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7271:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7272:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7273:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7274:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7275:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7276:       mp[cp]->product->api_user = product->api_user;
7277:       PetscCall(MatProductSetFromOptions(mp[cp]));
7278:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7279:       rmapt[cp] = 1;
7280:       cmapt[cp] = 1;
7281:       mptmp[cp] = PETSC_FALSE;
7282:       cp++;
7283:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7284:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7285:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7286:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7287:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7288:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7289:       mp[cp]->product->api_user = product->api_user;
7290:       PetscCall(MatProductSetFromOptions(mp[cp]));
7291:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7292:       rmapt[cp] = 1;
7293:       cmapt[cp] = 2;
7294:       cmapa[cp] = p->garray;
7295:       mptmp[cp] = PETSC_FALSE;
7296:       cp++;
7297:     }

7299:     /* A_off * P_other */
7300:     if (mmdata->P_oth) {
7301:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7302:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7303:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7304:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7305:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7306:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7307:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7308:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7309:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7310:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7311:       mp[cp]->product->api_user = product->api_user;
7312:       PetscCall(MatProductSetFromOptions(mp[cp]));
7313:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7314:       rmapt[cp] = 1;
7315:       cmapt[cp] = 2;
7316:       cmapa[cp] = P_oth_idx;
7317:       mptmp[cp] = PETSC_FALSE;
7318:       cp++;
7319:     }
7320:     break;

7322:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7323:     /* A is product->B */
7324:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7325:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7326:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7327:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7328:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7329:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7330:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7331:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7332:       mp[cp]->product->api_user = product->api_user;
7333:       PetscCall(MatProductSetFromOptions(mp[cp]));
7334:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7335:       PetscCall(ISGetIndices(glob, &globidx));
7336:       rmapt[cp] = 2;
7337:       rmapa[cp] = globidx;
7338:       cmapt[cp] = 2;
7339:       cmapa[cp] = globidx;
7340:       mptmp[cp] = PETSC_FALSE;
7341:       cp++;
7342:     } else {
7343:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7344:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7345:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7346:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7347:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7348:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7349:       mp[cp]->product->api_user = product->api_user;
7350:       PetscCall(MatProductSetFromOptions(mp[cp]));
7351:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7352:       PetscCall(ISGetIndices(glob, &globidx));
7353:       rmapt[cp] = 1;
7354:       cmapt[cp] = 2;
7355:       cmapa[cp] = globidx;
7356:       mptmp[cp] = PETSC_FALSE;
7357:       cp++;
7358:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7359:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7360:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7361:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7362:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7363:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7364:       mp[cp]->product->api_user = product->api_user;
7365:       PetscCall(MatProductSetFromOptions(mp[cp]));
7366:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7367:       rmapt[cp] = 2;
7368:       rmapa[cp] = p->garray;
7369:       cmapt[cp] = 2;
7370:       cmapa[cp] = globidx;
7371:       mptmp[cp] = PETSC_FALSE;
7372:       cp++;
7373:     }
7374:     break;
7375:   case MATPRODUCT_PtAP:
7376:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7377:     /* P is product->B */
7378:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7379:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7380:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7381:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7382:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7383:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7384:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7385:     mp[cp]->product->api_user = product->api_user;
7386:     PetscCall(MatProductSetFromOptions(mp[cp]));
7387:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7388:     PetscCall(ISGetIndices(glob, &globidx));
7389:     rmapt[cp] = 2;
7390:     rmapa[cp] = globidx;
7391:     cmapt[cp] = 2;
7392:     cmapa[cp] = globidx;
7393:     mptmp[cp] = PETSC_FALSE;
7394:     cp++;
7395:     if (mmdata->P_oth) {
7396:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7397:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7398:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7399:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7400:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7401:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7402:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7403:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7404:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7405:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7406:       mp[cp]->product->api_user = product->api_user;
7407:       PetscCall(MatProductSetFromOptions(mp[cp]));
7408:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7409:       mptmp[cp] = PETSC_TRUE;
7410:       cp++;
7411:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7412:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7413:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7414:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7415:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7416:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7417:       mp[cp]->product->api_user = product->api_user;
7418:       PetscCall(MatProductSetFromOptions(mp[cp]));
7419:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7420:       rmapt[cp] = 2;
7421:       rmapa[cp] = globidx;
7422:       cmapt[cp] = 2;
7423:       cmapa[cp] = P_oth_idx;
7424:       mptmp[cp] = PETSC_FALSE;
7425:       cp++;
7426:     }
7427:     break;
7428:   default:
7429:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7430:   }
7431:   /* sanity check */
7432:   if (size > 1)
7433:     for (i = 0; i < cp; i++) PetscCheck(rmapt[i] != 2 || hasoffproc, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Unexpected offproc map type for product %" PetscInt_FMT, i);

7435:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7436:   for (i = 0; i < cp; i++) {
7437:     mmdata->mp[i]    = mp[i];
7438:     mmdata->mptmp[i] = mptmp[i];
7439:   }
7440:   mmdata->cp             = cp;
7441:   C->product->data       = mmdata;
7442:   C->product->destroy    = MatProductCtxDestroy_MatMatMPIAIJBACKEND;
7443:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7445:   /* memory type */
7446:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7447:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7448:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7449:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7450:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7451:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7452:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7454:   /* prepare coo coordinates for values insertion */

7456:   /* count total nonzeros of those intermediate seqaij Mats
7457:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7458:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7459:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7460:   */
7461:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7462:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7463:     if (mptmp[cp]) continue;
7464:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7465:       const PetscInt *rmap = rmapa[cp];
7466:       const PetscInt  mr   = mp[cp]->rmap->n;
7467:       const PetscInt  rs   = C->rmap->rstart;
7468:       const PetscInt  re   = C->rmap->rend;
7469:       const PetscInt *ii   = mm->i;
7470:       for (i = 0; i < mr; i++) {
7471:         const PetscInt gr = rmap[i];
7472:         const PetscInt nz = ii[i + 1] - ii[i];
7473:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7474:         else ncoo_oown += nz;                  /* this row is local */
7475:       }
7476:     } else ncoo_d += mm->nz;
7477:   }

7479:   /*
7480:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7482:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7484:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7486:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7487:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7488:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7490:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7491:     Ex. coo_i[]: the beginning part (of size ncoo_d + ncoo_oown) stores i of local nonzeros, and the remaining part stores i of nonzeros I will receive.
7492:   */
7493:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7494:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7496:   /* gather (i,j) of nonzeros inserted by remote procs */
7497:   if (hasoffproc) {
7498:     PetscSF  msf;
7499:     PetscInt ncoo2, *coo_i2, *coo_j2;

7501:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7502:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7503:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7505:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7506:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7507:       PetscInt   *idxoff = mmdata->off[cp];
7508:       PetscInt   *idxown = mmdata->own[cp];
7509:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7510:         const PetscInt *rmap = rmapa[cp];
7511:         const PetscInt *cmap = cmapa[cp];
7512:         const PetscInt *ii   = mm->i;
7513:         PetscInt       *coi  = coo_i + ncoo_o;
7514:         PetscInt       *coj  = coo_j + ncoo_o;
7515:         const PetscInt  mr   = mp[cp]->rmap->n;
7516:         const PetscInt  rs   = C->rmap->rstart;
7517:         const PetscInt  re   = C->rmap->rend;
7518:         const PetscInt  cs   = C->cmap->rstart;
7519:         for (i = 0; i < mr; i++) {
7520:           const PetscInt *jj = mm->j + ii[i];
7521:           const PetscInt  gr = rmap[i];
7522:           const PetscInt  nz = ii[i + 1] - ii[i];
7523:           if (gr < rs || gr >= re) { /* this is an offproc row */
7524:             for (j = ii[i]; j < ii[i + 1]; j++) {
7525:               *coi++    = gr;
7526:               *idxoff++ = j;
7527:             }
7528:             if (!cmapt[cp]) { /* already global */
7529:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7530:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7531:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7532:             } else { /* offdiag */
7533:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7534:             }
7535:             ncoo_o += nz;
7536:           } else { /* this is a local row */
7537:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7538:           }
7539:         }
7540:       }
7541:       mmdata->off[cp + 1] = idxoff;
7542:       mmdata->own[cp + 1] = idxown;
7543:     }

7545:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7546:     PetscInt incoo_o;
7547:     PetscCall(PetscIntCast(ncoo_o, &incoo_o));
7548:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, incoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7549:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7550:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7551:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7552:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7553:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7554:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7555:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7556:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7557:     PetscCall(PetscFree2(coo_i, coo_j));
7558:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7559:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7560:     coo_i = coo_i2;
7561:     coo_j = coo_j2;
7562:   } else { /* no offproc values insertion */
7563:     ncoo = ncoo_d;
7564:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7566:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7567:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7568:     PetscCall(PetscSFSetUp(mmdata->sf));
7569:   }
7570:   mmdata->hasoffproc = hasoffproc;

7572:   /* gather (i,j) of nonzeros inserted locally */
7573:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7574:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7575:     PetscInt       *coi  = coo_i + ncoo_d;
7576:     PetscInt       *coj  = coo_j + ncoo_d;
7577:     const PetscInt *jj   = mm->j;
7578:     const PetscInt *ii   = mm->i;
7579:     const PetscInt *cmap = cmapa[cp];
7580:     const PetscInt *rmap = rmapa[cp];
7581:     const PetscInt  mr   = mp[cp]->rmap->n;
7582:     const PetscInt  rs   = C->rmap->rstart;
7583:     const PetscInt  re   = C->rmap->rend;
7584:     const PetscInt  cs   = C->cmap->rstart;

7586:     if (mptmp[cp]) continue;
7587:     if (rmapt[cp] == 1) { /* consecutive rows */
7588:       /* fill coo_i */
7589:       for (i = 0; i < mr; i++) {
7590:         const PetscInt gr = i + rs;
7591:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7592:       }
7593:       /* fill coo_j */
7594:       if (!cmapt[cp]) { /* type-0, already global */
7595:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7596:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7597:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7598:       } else {                                            /* type-2, local to global for sparse columns */
7599:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7600:       }
7601:       ncoo_d += mm->nz;
7602:     } else if (rmapt[cp] == 2) { /* sparse rows */
7603:       for (i = 0; i < mr; i++) {
7604:         const PetscInt *jj = mm->j + ii[i];
7605:         const PetscInt  gr = rmap[i];
7606:         const PetscInt  nz = ii[i + 1] - ii[i];
7607:         if (gr >= rs && gr < re) { /* local rows */
7608:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7609:           if (!cmapt[cp]) { /* type-0, already global */
7610:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7611:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7612:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7613:           } else { /* type-2, local to global for sparse columns */
7614:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7615:           }
7616:           ncoo_d += nz;
7617:         }
7618:       }
7619:     }
7620:   }
7621:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7622:   PetscCall(ISDestroy(&glob));
7623:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7624:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7625:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7626:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7628:   /* set block sizes */
7629:   A = product->A;
7630:   P = product->B;
7631:   switch (ptype) {
7632:   case MATPRODUCT_PtAP:
7633:     PetscCall(MatSetBlockSizes(C, P->cmap->bs, P->cmap->bs));
7634:     break;
7635:   case MATPRODUCT_RARt:
7636:     PetscCall(MatSetBlockSizes(C, P->rmap->bs, P->rmap->bs));
7637:     break;
7638:   case MATPRODUCT_ABC:
7639:     PetscCall(MatSetBlockSizesFromMats(C, A, product->C));
7640:     break;
7641:   case MATPRODUCT_AB:
7642:     PetscCall(MatSetBlockSizesFromMats(C, A, P));
7643:     break;
7644:   case MATPRODUCT_AtB:
7645:     PetscCall(MatSetBlockSizes(C, A->cmap->bs, P->cmap->bs));
7646:     break;
7647:   case MATPRODUCT_ABt:
7648:     PetscCall(MatSetBlockSizes(C, A->rmap->bs, P->rmap->bs));
7649:     break;
7650:   default:
7651:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for ProductType %s", MatProductTypes[ptype]);
7652:   }

7654:   /* preallocate with COO data */
7655:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7656:   PetscCall(PetscFree2(coo_i, coo_j));
7657:   PetscFunctionReturn(PETSC_SUCCESS);
7658: }

7660: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7661: {
7662:   Mat_Product *product = mat->product;
7663: #if PetscDefined(HAVE_DEVICE)
7664:   PetscBool match  = PETSC_FALSE;
7665:   PetscBool usecpu = PETSC_FALSE;
7666: #else
7667:   PetscBool match = PETSC_TRUE;
7668: #endif

7670:   PetscFunctionBegin;
7671:   MatCheckProduct(mat, 1);
7672: #if PetscDefined(HAVE_DEVICE)
7673:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7674:   if (match) { /* we can always fallback to the CPU if requested */
7675:     switch (product->type) {
7676:     case MATPRODUCT_AB:
7677:       if (product->api_user) {
7678:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7679:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7680:         PetscOptionsEnd();
7681:       } else {
7682:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7683:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7684:         PetscOptionsEnd();
7685:       }
7686:       break;
7687:     case MATPRODUCT_AtB:
7688:       if (product->api_user) {
7689:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7690:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7691:         PetscOptionsEnd();
7692:       } else {
7693:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7694:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7695:         PetscOptionsEnd();
7696:       }
7697:       break;
7698:     case MATPRODUCT_PtAP:
7699:       if (product->api_user) {
7700:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7701:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7702:         PetscOptionsEnd();
7703:       } else {
7704:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7705:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7706:         PetscOptionsEnd();
7707:       }
7708:       break;
7709:     default:
7710:       break;
7711:     }
7712:     match = (PetscBool)!usecpu;
7713:   }
7714: #endif
7715:   if (match) {
7716:     switch (product->type) {
7717:     case MATPRODUCT_AB:
7718:     case MATPRODUCT_AtB:
7719:     case MATPRODUCT_PtAP:
7720:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7721:       break;
7722:     default:
7723:       break;
7724:     }
7725:   }
7726:   /* fallback to MPIAIJ ops */
7727:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7728:   PetscFunctionReturn(PETSC_SUCCESS);
7729: }

7731: /*
7732:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7734:    n - the number of block indices in cc[]
7735:    cc - the block indices (must be large enough to contain the indices)
7736: */
7737: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7738: {
7739:   PetscInt        cnt = -1, nidx, j;
7740:   const PetscInt *idx;

7742:   PetscFunctionBegin;
7743:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7744:   if (nidx) {
7745:     cnt     = 0;
7746:     cc[cnt] = idx[0] / bs;
7747:     for (j = 1; j < nidx; j++) {
7748:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7749:     }
7750:   }
7751:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7752:   *n = cnt + 1;
7753:   PetscFunctionReturn(PETSC_SUCCESS);
7754: }

7756: /*
7757:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7759:     ncollapsed - the number of block indices
7760:     collapsed - the block indices (must be large enough to contain the indices)
7761: */
7762: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7763: {
7764:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7766:   PetscFunctionBegin;
7767:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7768:   for (i = start + 1; i < start + bs; i++) {
7769:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7770:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7771:     cprevtmp = cprev;
7772:     cprev    = merged;
7773:     merged   = cprevtmp;
7774:   }
7775:   *ncollapsed = nprev;
7776:   if (collapsed) *collapsed = cprev;
7777:   PetscFunctionReturn(PETSC_SUCCESS);
7778: }

7780: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7781: {
7782:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7783:   MPI_Comm  comm;
7784:   Mat       Gmat;
7785:   PetscBool ismpiaij, isseqaij;
7786:   Mat       a, b, c;
7787:   MatType   jtype;

7789:   PetscFunctionBegin;
7790:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7791:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7792:   PetscCall(MatGetSize(Amat, &MM, &NN));
7793:   PetscCall(MatGetBlockSize(Amat, &bs));
7794:   nloc = (Iend - Istart) / bs;

7796:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7797:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7798:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7800:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7801:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7802:      implementation */
7803:   if (bs > 1) {
7804:     PetscCall(MatGetType(Amat, &jtype));
7805:     PetscCall(MatCreate(comm, &Gmat));
7806:     PetscCall(MatSetType(Gmat, jtype));
7807:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7808:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7809:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7810:       PetscInt  *d_nnz, *o_nnz;
7811:       MatScalar *aa, val, *AA;
7812:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;

7814:       if (isseqaij) {
7815:         a = Amat;
7816:         b = NULL;
7817:       } else {
7818:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7819:         a             = d->A;
7820:         b             = d->B;
7821:       }
7822:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7823:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7824:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7825:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7826:         const PetscInt *cols1, *cols2;

7828:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7829:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7830:           nnz[brow / bs] = nc2 / bs;
7831:           if (nc2 % bs) ok = 0;
7832:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7833:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7834:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7835:             if (nc1 != nc2) ok = 0;
7836:             else {
7837:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7838:                 if (cols1[jj] != cols2[jj]) ok = 0;
7839:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7840:               }
7841:             }
7842:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7843:           }
7844:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7845:           if (!ok) {
7846:             PetscCall(PetscFree2(d_nnz, o_nnz));
7847:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7848:             goto old_bs;
7849:           }
7850:         }
7851:       }
7852:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7853:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7854:       PetscCall(PetscFree2(d_nnz, o_nnz));
7855:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7856:       // diag
7857:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7858:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;

7860:         ai = aseq->i;
7861:         n  = ai[brow + 1] - ai[brow];
7862:         aj = aseq->j + ai[brow];
7863:         for (PetscInt k = 0; k < n; k += bs) {   // block columns
7864:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7865:           val        = 0;
7866:           if (index_size == 0) {
7867:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7868:               aa = aseq->a + ai[brow + ii] + k;
7869:               for (PetscInt jj = 0; jj < bs; jj++) {    // columns in block
7870:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7871:               }
7872:             }
7873:           } else {                                            // use (index,index) value if provided
7874:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7875:               PetscInt ii = index[iii];
7876:               aa          = aseq->a + ai[brow + ii] + k;
7877:               for (PetscInt jjj = 0; jjj < index_size; jjj++) { // columns in block
7878:                 PetscInt jj = index[jjj];
7879:                 val += PetscAbs(PetscRealPart(aa[jj]));
7880:               }
7881:             }
7882:           }
7883:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7884:           AA[k / bs] = val;
7885:         }
7886:         grow = Istart / bs + brow / bs;
7887:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7888:       }
7889:       // off-diag
7890:       if (ismpiaij) {
7891:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7892:         const PetscScalar *vals;
7893:         const PetscInt    *cols, *garray = aij->garray;

7895:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7896:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7897:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7898:           for (PetscInt k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7899:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7900:             AA[k / bs] = 0;
7901:             AJ[cidx]   = garray[cols[k]] / bs;
7902:           }
7903:           nc = ncols / bs;
7904:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7905:           if (index_size == 0) {
7906:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7907:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7908:               for (PetscInt k = 0; k < ncols; k += bs) {
7909:                 for (PetscInt jj = 0; jj < bs; jj++) { // cols in block
7910:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7911:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7912:                 }
7913:               }
7914:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7915:             }
7916:           } else {                                            // use (index,index) value if provided
7917:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7918:               PetscInt ii = index[iii];
7919:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7920:               for (PetscInt k = 0; k < ncols; k += bs) {
7921:                 for (PetscInt jjj = 0; jjj < index_size; jjj++) { // cols in block
7922:                   PetscInt jj = index[jjj];
7923:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7924:                 }
7925:               }
7926:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7927:             }
7928:           }
7929:           grow = Istart / bs + brow / bs;
7930:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7931:         }
7932:       }
7933:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7934:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7935:       PetscCall(PetscFree2(AA, AJ));
7936:     } else {
7937:       const PetscScalar *vals;
7938:       const PetscInt    *idx;
7939:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7940:     old_bs:
7941:       /*
7942:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7943:        */
7944:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7945:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7946:       if (isseqaij) {
7947:         PetscInt max_d_nnz;

7949:         /*
7950:          Determine exact preallocation count for (sequential) scalar matrix
7951:          */
7952:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7953:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7954:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7955:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7956:         PetscCall(PetscFree3(w0, w1, w2));
7957:       } else if (ismpiaij) {
7958:         Mat             Daij, Oaij;
7959:         const PetscInt *garray;
7960:         PetscInt        max_d_nnz;

7962:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7963:         /*
7964:          Determine exact preallocation count for diagonal block portion of scalar matrix
7965:          */
7966:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7967:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7968:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7969:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7970:         PetscCall(PetscFree3(w0, w1, w2));
7971:         /*
7972:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7973:          */
7974:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7975:           o_nnz[jj] = 0;
7976:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7977:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7978:             o_nnz[jj] += ncols;
7979:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7980:           }
7981:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7982:         }
7983:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
7984:       /* get scalar copy (norms) of matrix */
7985:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7986:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7987:       PetscCall(PetscFree2(d_nnz, o_nnz));
7988:       for (Ii = Istart; Ii < Iend; Ii++) {
7989:         PetscInt dest_row = Ii / bs;

7991:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
7992:         for (jj = 0; jj < ncols; jj++) {
7993:           PetscInt    dest_col = idx[jj] / bs;
7994:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));

7996:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
7997:         }
7998:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
7999:       }
8000:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
8001:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
8002:     }
8003:   } else {
8004:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
8005:     else {
8006:       Gmat = Amat;
8007:       PetscCall(PetscObjectReference((PetscObject)Gmat));
8008:     }
8009:     if (isseqaij) {
8010:       a = Gmat;
8011:       b = NULL;
8012:     } else {
8013:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
8014:       a             = d->A;
8015:       b             = d->B;
8016:     }
8017:     if (filter >= 0 || scale) {
8018:       /* take absolute value of each entry */
8019:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
8020:         MatInfo      info;
8021:         PetscScalar *avals;

8023:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
8024:         PetscCall(MatSeqAIJGetArray(c, &avals));
8025:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
8026:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
8027:       }
8028:     }
8029:   }
8030:   if (symmetrize) {
8031:     PetscBool isset, issym;

8033:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
8034:     if (!isset || !issym) {
8035:       Mat matTrans;

8037:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
8038:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
8039:       PetscCall(MatDestroy(&matTrans));
8040:     }
8041:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
8042:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
8043:   if (scale) {
8044:     /* scale c for all diagonal values = 1 or -1 */
8045:     Vec diag;

8047:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8048:     PetscCall(MatGetDiagonal(Gmat, diag));
8049:     PetscCall(VecReciprocal(diag));
8050:     PetscCall(VecSqrtAbs(diag));
8051:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8052:     PetscCall(VecDestroy(&diag));
8053:   }
8054:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));
8055:   if (filter >= 0) {
8056:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8057:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8058:   }
8059:   *a_Gmat = Gmat;
8060:   PetscFunctionReturn(PETSC_SUCCESS);
8061: }

8063: PETSC_INTERN PetscErrorCode MatGetCurrentMemType_MPIAIJ(Mat A, PetscMemType *memtype)
8064: {
8065:   Mat_MPIAIJ  *mpiaij = (Mat_MPIAIJ *)A->data;
8066:   PetscMemType mD = PETSC_MEMTYPE_HOST, mO = PETSC_MEMTYPE_HOST;

8068:   PetscFunctionBegin;
8069:   if (mpiaij->A) PetscCall(MatGetCurrentMemType(mpiaij->A, &mD));
8070:   if (mpiaij->B) PetscCall(MatGetCurrentMemType(mpiaij->B, &mO));
8071:   *memtype = (mD == mO) ? mD : PETSC_MEMTYPE_HOST;
8072:   PetscFunctionReturn(PETSC_SUCCESS);
8073: }

8075: /*
8076:     Special version for direct calls from Fortran
8077: */

8079: /* Change these macros so can be used in void function */
8080: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8081: #undef PetscCall
8082: #define PetscCall(...) \
8083:   do { \
8084:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8085:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8086:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8087:       return; \
8088:     } \
8089:   } while (0)

8091: #undef SETERRQ
8092: #define SETERRQ(comm, ierr, ...) \
8093:   do { \
8094:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8095:     return; \
8096:   } while (0)

8098: #if PetscDefined(HAVE_FORTRAN_CAPS)
8099:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8100: #elif !PetscDefined(HAVE_FORTRAN_UNDERSCORE)
8101:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8102: #else
8103: #endif
8104: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8105: {
8106:   Mat         mat = *mmat;
8107:   PetscInt    m = *mm, n = *mn;
8108:   InsertMode  addv = *maddv;
8109:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8110:   PetscScalar value;

8112:   MatCheckPreallocated(mat, 1);
8113:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8114:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8115:   {
8116:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8117:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8118:     PetscBool roworiented = aij->roworiented;

8120:     /* Some Variables required in the macro */
8121:     Mat         A     = aij->A;
8122:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8123:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8124:     MatScalar  *aa;
8125:     PetscBool   ignorezeroentries = (a->ignorezeroentries && addv == ADD_VALUES) ? PETSC_TRUE : PETSC_FALSE;
8126:     Mat         B                 = aij->B;
8127:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8128:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8129:     MatScalar  *ba;
8130:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8131:      * cannot use "#if defined" inside a macro. */
8132:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8134:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8135:     PetscInt   nonew = a->nonew;
8136:     MatScalar *ap1, *ap2;

8138:     PetscFunctionBegin;
8139:     PetscCall(MatSeqAIJGetArray(A, &aa));
8140:     PetscCall(MatSeqAIJGetArray(B, &ba));
8141:     for (i = 0; i < m; i++) {
8142:       if (im[i] < 0) continue;
8143:       PetscCheck(im[i] < mat->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Row too large: row %" PetscInt_FMT " max %" PetscInt_FMT, im[i], mat->rmap->N - 1);
8144:       if (im[i] >= rstart && im[i] < rend) {
8145:         row      = im[i] - rstart;
8146:         lastcol1 = -1;
8147:         rp1      = aj + ai[row];
8148:         ap1      = aa + ai[row];
8149:         rmax1    = aimax[row];
8150:         nrow1    = ailen[row];
8151:         low1     = 0;
8152:         high1    = nrow1;
8153:         lastcol2 = -1;
8154:         rp2      = bj + bi[row];
8155:         ap2      = ba + bi[row];
8156:         rmax2    = bimax[row];
8157:         nrow2    = bilen[row];
8158:         low2     = 0;
8159:         high2    = nrow2;

8161:         for (j = 0; j < n; j++) {
8162:           if (roworiented) value = v[i * n + j];
8163:           else value = v[i + j * m];
8164:           if (ignorezeroentries && value == 0.0 && addv == ADD_VALUES && im[i] != in[j]) continue;
8165:           if (in[j] >= cstart && in[j] < cend) {
8166:             col = in[j] - cstart;
8167:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8168:           } else if (in[j] < 0) continue;
8169:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8170:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8171:           } else {
8172:             if (mat->was_assembled) {
8173:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8174: #if PetscDefined(USE_CTABLE)
8175:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8176:               col--;
8177: #else
8178:               col = aij->colmap[in[j]] - 1;
8179: #endif
8180:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8181:                 PetscCall(MatDisAssemble_MPIAIJ(mat, PETSC_FALSE));
8182:                 col = in[j];
8183:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8184:                 B        = aij->B;
8185:                 b        = (Mat_SeqAIJ *)B->data;
8186:                 bimax    = b->imax;
8187:                 bi       = b->i;
8188:                 bilen    = b->ilen;
8189:                 bj       = b->j;
8190:                 rp2      = bj + bi[row];
8191:                 ap2      = ba + bi[row];
8192:                 rmax2    = bimax[row];
8193:                 nrow2    = bilen[row];
8194:                 low2     = 0;
8195:                 high2    = nrow2;
8196:                 bm       = aij->B->rmap->n;
8197:                 ba       = b->a;
8198:                 inserted = PETSC_FALSE;
8199:               }
8200:             } else col = in[j];
8201:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8202:           }
8203:         }
8204:       } else if (!aij->donotstash) {
8205:         if (roworiented) {
8206:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
8207:         } else {
8208:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && addv == ADD_VALUES)));
8209:         }
8210:       }
8211:     }
8212:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8213:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8214:   }
8215:   PetscFunctionReturnVoid();
8216: }

8218: /* Undefining these here since they were redefined from their original definition above! No
8219:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8220:  * original definitions */
8221: #undef PetscCall
8222: #undef SETERRQ