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 defined(PETSC_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, "MatIsTranspose_C", NULL));
 67:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocation_C", NULL));
 68:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetPreallocation_C", NULL));
 69:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatResetHash_C", NULL));
 70:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetPreallocationCSR_C", NULL));
 71:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatDiagonalScaleLocal_C", NULL));
 72:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpibaij_C", NULL));
 73:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisbaij_C", NULL));
 74: #if defined(PETSC_HAVE_CUDA)
 75:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcusparse_C", NULL));
 76: #endif
 77: #if defined(PETSC_HAVE_HIP)
 78:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijhipsparse_C", NULL));
 79: #endif
 80: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
 81:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijkokkos_C", NULL));
 82: #endif
 83:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpidense_C", NULL));
 84: #if defined(PETSC_HAVE_ELEMENTAL)
 85:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_elemental_C", NULL));
 86: #endif
 87: #if defined(PETSC_HAVE_SCALAPACK)
 88:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_scalapack_C", NULL));
 89: #endif
 90: #if defined(PETSC_HAVE_HYPRE)
 91:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_hypre_C", NULL));
 92:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", NULL));
 93: #endif
 94:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
 95:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_is_mpiaij_C", NULL));
 96:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_mpiaij_mpiaij_C", NULL));
 97:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatMPIAIJSetUseScalableIncreaseOverlap_C", NULL));
 98:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijperm_C", NULL));
 99:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijsell_C", NULL));
100: #if defined(PETSC_HAVE_MKL_SPARSE)
101:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijmkl_C", NULL));
102: #endif
103:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpiaijcrl_C", NULL));
104:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_is_C", NULL));
105:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConvert_mpiaij_mpisell_C", NULL));
106:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetPreallocationCOO_C", NULL));
107:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatSetValuesCOO_C", NULL));
108:   PetscFunctionReturn(PETSC_SUCCESS);
109: }

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

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

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

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

134: /*MC
135:    MATAIJ - MATAIJ = "aij" - A matrix type to be used for sparse matrices.

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

143:    Options Database Key:
144: . -mat_type aij - sets the matrix type to `MATAIJ` during a call to `MatSetFromOptions()`

146:   Developer Note:
147:   Level: beginner

149:     Subclasses include `MATAIJCUSPARSE`, `MATAIJPERM`, `MATAIJSELL`, `MATAIJMKL`, `MATAIJCRL`, `MATAIJKOKKOS`,and also automatically switches over to use inodes when
150:    enough exist.

152: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateAIJ()`, `MatCreateSeqAIJ()`, `MATSEQAIJ`, `MATMPIAIJ`
153: M*/

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

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

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

167:   Level: beginner

169: .seealso: [](ch_matrices), `Mat`, `MatCreateMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`, `MATSEQAIJCRL`, `MATMPIAIJCRL`
170: M*/

172: static PetscErrorCode MatBindToCPU_MPIAIJ(Mat A, PetscBool flg)
173: {
174:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

176:   PetscFunctionBegin;
177: #if defined(PETSC_HAVE_CUDA) || defined(PETSC_HAVE_HIP) || defined(PETSC_HAVE_VIENNACL)
178:   A->boundtocpu = flg;
179: #endif
180:   if (a->A) PetscCall(MatBindToCPU(a->A, flg));
181:   if (a->B) PetscCall(MatBindToCPU(a->B, flg));

183:   /* In addition to binding the diagonal and off-diagonal matrices, bind the local vectors used for matrix-vector products.
184:    * This maybe seems a little odd for a MatBindToCPU() call to do, but it makes no sense for the binding of these vectors
185:    * to differ from the parent matrix. */
186:   if (a->lvec) PetscCall(VecBindToCPU(a->lvec, flg));
187:   if (a->diag) PetscCall(VecBindToCPU(a->diag, flg));
188:   PetscFunctionReturn(PETSC_SUCCESS);
189: }

191: static PetscErrorCode MatSetBlockSizes_MPIAIJ(Mat M, PetscInt rbs, PetscInt cbs)
192: {
193:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)M->data;

195:   PetscFunctionBegin;
196:   if (mat->A) {
197:     PetscCall(MatSetBlockSizes(mat->A, rbs, cbs));
198:     PetscCall(MatSetBlockSizes(mat->B, rbs, 1));
199:   }
200:   PetscFunctionReturn(PETSC_SUCCESS);
201: }

203: static PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M, IS *keptrows)
204: {
205:   Mat_MPIAIJ      *mat = (Mat_MPIAIJ *)M->data;
206:   Mat_SeqAIJ      *a   = (Mat_SeqAIJ *)mat->A->data;
207:   Mat_SeqAIJ      *b   = (Mat_SeqAIJ *)mat->B->data;
208:   const PetscInt  *ia, *ib;
209:   const MatScalar *aa, *bb, *aav, *bav;
210:   PetscInt         na, nb, i, j, *rows, cnt = 0, n0rows;
211:   PetscInt         m = M->rmap->n, rstart = M->rmap->rstart;

213:   PetscFunctionBegin;
214:   *keptrows = NULL;

216:   ia = a->i;
217:   ib = b->i;
218:   PetscCall(MatSeqAIJGetArrayRead(mat->A, &aav));
219:   PetscCall(MatSeqAIJGetArrayRead(mat->B, &bav));
220:   for (i = 0; i < m; i++) {
221:     na = ia[i + 1] - ia[i];
222:     nb = ib[i + 1] - ib[i];
223:     if (!na && !nb) {
224:       cnt++;
225:       goto ok1;
226:     }
227:     aa = aav + ia[i];
228:     for (j = 0; j < na; j++) {
229:       if (aa[j] != 0.0) goto ok1;
230:     }
231:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
232:     for (j = 0; j < nb; j++) {
233:       if (bb[j] != 0.0) goto ok1;
234:     }
235:     cnt++;
236:   ok1:;
237:   }
238:   PetscCallMPI(MPIU_Allreduce(&cnt, &n0rows, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)M)));
239:   if (!n0rows) {
240:     PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
241:     PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
242:     PetscFunctionReturn(PETSC_SUCCESS);
243:   }
244:   PetscCall(PetscMalloc1(M->rmap->n - cnt, &rows));
245:   cnt = 0;
246:   for (i = 0; i < m; i++) {
247:     na = ia[i + 1] - ia[i];
248:     nb = ib[i + 1] - ib[i];
249:     if (!na && !nb) continue;
250:     aa = aav + ia[i];
251:     for (j = 0; j < na; j++) {
252:       if (aa[j] != 0.0) {
253:         rows[cnt++] = rstart + i;
254:         goto ok2;
255:       }
256:     }
257:     bb = PetscSafePointerPlusOffset(bav, ib[i]);
258:     for (j = 0; j < nb; j++) {
259:       if (bb[j] != 0.0) {
260:         rows[cnt++] = rstart + i;
261:         goto ok2;
262:       }
263:     }
264:   ok2:;
265:   }
266:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), cnt, rows, PETSC_OWN_POINTER, keptrows));
267:   PetscCall(MatSeqAIJRestoreArrayRead(mat->A, &aav));
268:   PetscCall(MatSeqAIJRestoreArrayRead(mat->B, &bav));
269:   PetscFunctionReturn(PETSC_SUCCESS);
270: }

272: static PetscErrorCode MatDiagonalSet_MPIAIJ(Mat Y, Vec D, InsertMode is)
273: {
274:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)Y->data;
275:   PetscBool   cong;

277:   PetscFunctionBegin;
278:   PetscCall(MatHasCongruentLayouts(Y, &cong));
279:   if (Y->assembled && cong) {
280:     PetscCall(MatDiagonalSet(aij->A, D, is));
281:   } else {
282:     PetscCall(MatDiagonalSet_Default(Y, D, is));
283:   }
284:   PetscFunctionReturn(PETSC_SUCCESS);
285: }

287: static PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M, IS *zrows)
288: {
289:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)M->data;
290:   PetscInt    i, rstart, nrows, *rows;

292:   PetscFunctionBegin;
293:   *zrows = NULL;
294:   PetscCall(MatFindZeroDiagonals_SeqAIJ_Private(aij->A, &nrows, &rows));
295:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));
296:   for (i = 0; i < nrows; i++) rows[i] += rstart;
297:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)M), nrows, rows, PETSC_OWN_POINTER, zrows));
298:   PetscFunctionReturn(PETSC_SUCCESS);
299: }

301: static PetscErrorCode MatGetColumnReductions_MPIAIJ(Mat A, PetscInt type, PetscReal *reductions)
302: {
303:   Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)A->data;
304:   PetscInt           i, m, n, *garray = aij->garray;
305:   Mat_SeqAIJ        *a_aij = (Mat_SeqAIJ *)aij->A->data;
306:   Mat_SeqAIJ        *b_aij = (Mat_SeqAIJ *)aij->B->data;
307:   PetscReal         *work;
308:   const PetscScalar *dummy;
309:   PetscMPIInt        in;

311:   PetscFunctionBegin;
312:   PetscCall(MatGetSize(A, &m, &n));
313:   PetscCall(PetscCalloc1(n, &work));
314:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &dummy));
315:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &dummy));
316:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &dummy));
317:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &dummy));
318:   if (type == NORM_2) {
319:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i] * a_aij->a[i]);
320:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i] * b_aij->a[i]);
321:   } else if (type == NORM_1) {
322:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
323:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
324:   } else if (type == NORM_INFINITY) {
325:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
326:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]), work[garray[b_aij->j[i]]]);
327:   } else if (type == REDUCTION_SUM_REALPART || type == REDUCTION_MEAN_REALPART) {
328:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscRealPart(a_aij->a[i]);
329:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscRealPart(b_aij->a[i]);
330:   } else if (type == REDUCTION_SUM_IMAGINARYPART || type == REDUCTION_MEAN_IMAGINARYPART) {
331:     for (i = 0; i < a_aij->i[aij->A->rmap->n]; i++) work[A->cmap->rstart + a_aij->j[i]] += PetscImaginaryPart(a_aij->a[i]);
332:     for (i = 0; i < b_aij->i[aij->B->rmap->n]; i++) work[garray[b_aij->j[i]]] += PetscImaginaryPart(b_aij->a[i]);
333:   } else SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONG, "Unknown reduction type");
334:   PetscCall(PetscMPIIntCast(n, &in));
335:   if (type == NORM_INFINITY) {
336:     PetscCallMPI(MPIU_Allreduce(work, reductions, in, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)A)));
337:   } else {
338:     PetscCallMPI(MPIU_Allreduce(work, reductions, in, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)A)));
339:   }
340:   PetscCall(PetscFree(work));
341:   if (type == NORM_2) {
342:     for (i = 0; i < n; i++) reductions[i] = PetscSqrtReal(reductions[i]);
343:   } else if (type == REDUCTION_MEAN_REALPART || type == REDUCTION_MEAN_IMAGINARYPART) {
344:     for (i = 0; i < n; i++) reductions[i] /= m;
345:   }
346:   PetscFunctionReturn(PETSC_SUCCESS);
347: }

349: static PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A, IS *is)
350: {
351:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)A->data;
352:   IS              sis, gis;
353:   const PetscInt *isis, *igis;
354:   PetscInt        n, *iis, nsis, ngis, rstart, i;

356:   PetscFunctionBegin;
357:   PetscCall(MatFindOffBlockDiagonalEntries(a->A, &sis));
358:   PetscCall(MatFindNonzeroRows(a->B, &gis));
359:   PetscCall(ISGetSize(gis, &ngis));
360:   PetscCall(ISGetSize(sis, &nsis));
361:   PetscCall(ISGetIndices(sis, &isis));
362:   PetscCall(ISGetIndices(gis, &igis));

364:   PetscCall(PetscMalloc1(ngis + nsis, &iis));
365:   PetscCall(PetscArraycpy(iis, igis, ngis));
366:   PetscCall(PetscArraycpy(iis + ngis, isis, nsis));
367:   n = ngis + nsis;
368:   PetscCall(PetscSortRemoveDupsInt(&n, iis));
369:   PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
370:   for (i = 0; i < n; i++) iis[i] += rstart;
371:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)A), n, iis, PETSC_OWN_POINTER, is));

373:   PetscCall(ISRestoreIndices(sis, &isis));
374:   PetscCall(ISRestoreIndices(gis, &igis));
375:   PetscCall(ISDestroy(&sis));
376:   PetscCall(ISDestroy(&gis));
377:   PetscFunctionReturn(PETSC_SUCCESS);
378: }

380: /*
381:   Local utility routine that creates a mapping from the global column
382: number to the local number in the off-diagonal part of the local
383: storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
384: a slightly higher hash table cost; without it it is not scalable (each processor
385: has an order N integer array but is fast to access.
386: */
387: PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
388: {
389:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
390:   PetscInt    n   = aij->B->cmap->n, i;

392:   PetscFunctionBegin;
393:   PetscCheck(!n || aij->garray, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MPIAIJ Matrix was assembled but is missing garray");
394: #if defined(PETSC_USE_CTABLE)
395:   PetscCall(PetscHMapICreateWithSize(n, &aij->colmap));
396:   for (i = 0; i < n; i++) PetscCall(PetscHMapISet(aij->colmap, aij->garray[i] + 1, i + 1));
397: #else
398:   PetscCall(PetscCalloc1(mat->cmap->N + 1, &aij->colmap));
399:   for (i = 0; i < n; i++) aij->colmap[aij->garray[i]] = i + 1;
400: #endif
401:   PetscFunctionReturn(PETSC_SUCCESS);
402: }

404: #define MatSetValues_SeqAIJ_A_Private(row, col, value, addv, orow, ocol) \
405:   do { \
406:     if (col <= lastcol1) low1 = 0; \
407:     else high1 = nrow1; \
408:     lastcol1 = col; \
409:     while (high1 - low1 > 5) { \
410:       t = (low1 + high1) / 2; \
411:       if (rp1[t] > col) high1 = t; \
412:       else low1 = t; \
413:     } \
414:     for (_i = low1; _i < high1; _i++) { \
415:       if (rp1[_i] > col) break; \
416:       if (rp1[_i] == col) { \
417:         if (addv == ADD_VALUES) { \
418:           ap1[_i] += value; \
419:           /* Not sure LogFlops will slow dow the code or not */ \
420:           (void)PetscLogFlops(1.0); \
421:         } else ap1[_i] = value; \
422:         goto a_noinsert; \
423:       } \
424:     } \
425:     if (value == 0.0 && ignorezeroentries && row != col) { \
426:       low1  = 0; \
427:       high1 = nrow1; \
428:       goto a_noinsert; \
429:     } \
430:     if (nonew == 1) { \
431:       low1  = 0; \
432:       high1 = nrow1; \
433:       goto a_noinsert; \
434:     } \
435:     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); \
436:     MatSeqXAIJReallocateAIJ(A, am, 1, nrow1, row, col, rmax1, aa, ai, aj, rp1, ap1, aimax, nonew, MatScalar); \
437:     N = nrow1++ - 1; \
438:     a->nz++; \
439:     high1++; \
440:     /* shift up all the later entries in this row */ \
441:     PetscCall(PetscArraymove(rp1 + _i + 1, rp1 + _i, N - _i + 1)); \
442:     PetscCall(PetscArraymove(ap1 + _i + 1, ap1 + _i, N - _i + 1)); \
443:     rp1[_i] = col; \
444:     ap1[_i] = value; \
445:   a_noinsert:; \
446:     ailen[row] = nrow1; \
447:   } while (0)

449: #define MatSetValues_SeqAIJ_B_Private(row, col, value, addv, orow, ocol) \
450:   do { \
451:     if (col <= lastcol2) low2 = 0; \
452:     else high2 = nrow2; \
453:     lastcol2 = col; \
454:     while (high2 - low2 > 5) { \
455:       t = (low2 + high2) / 2; \
456:       if (rp2[t] > col) high2 = t; \
457:       else low2 = t; \
458:     } \
459:     for (_i = low2; _i < high2; _i++) { \
460:       if (rp2[_i] > col) break; \
461:       if (rp2[_i] == col) { \
462:         if (addv == ADD_VALUES) { \
463:           ap2[_i] += value; \
464:           (void)PetscLogFlops(1.0); \
465:         } else ap2[_i] = value; \
466:         goto b_noinsert; \
467:       } \
468:     } \
469:     if (value == 0.0 && ignorezeroentries) { \
470:       low2  = 0; \
471:       high2 = nrow2; \
472:       goto b_noinsert; \
473:     } \
474:     if (nonew == 1) { \
475:       low2  = 0; \
476:       high2 = nrow2; \
477:       goto b_noinsert; \
478:     } \
479:     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); \
480:     MatSeqXAIJReallocateAIJ(B, bm, 1, nrow2, row, col, rmax2, ba, bi, bj, rp2, ap2, bimax, nonew, MatScalar); \
481:     N = nrow2++ - 1; \
482:     b->nz++; \
483:     high2++; \
484:     /* shift up all the later entries in this row */ \
485:     PetscCall(PetscArraymove(rp2 + _i + 1, rp2 + _i, N - _i + 1)); \
486:     PetscCall(PetscArraymove(ap2 + _i + 1, ap2 + _i, N - _i + 1)); \
487:     rp2[_i] = col; \
488:     ap2[_i] = value; \
489:   b_noinsert:; \
490:     bilen[row] = nrow2; \
491:   } while (0)

493: static PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A, PetscInt row, const PetscScalar v[])
494: {
495:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)A->data;
496:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)mat->A->data, *b = (Mat_SeqAIJ *)mat->B->data;
497:   PetscInt     l, *garray                         = mat->garray, diag;
498:   PetscScalar *aa, *ba;

500:   PetscFunctionBegin;
501:   /* code only works for square matrices A */

503:   /* find size of row to the left of the diagonal part */
504:   PetscCall(MatGetOwnershipRange(A, &diag, NULL));
505:   row = row - diag;
506:   for (l = 0; l < b->i[row + 1] - b->i[row]; l++) {
507:     if (garray[b->j[b->i[row] + l]] > diag) break;
508:   }
509:   if (l) {
510:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
511:     PetscCall(PetscArraycpy(ba + b->i[row], v, l));
512:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
513:   }

515:   /* diagonal part */
516:   if (a->i[row + 1] - a->i[row]) {
517:     PetscCall(MatSeqAIJGetArray(mat->A, &aa));
518:     PetscCall(PetscArraycpy(aa + a->i[row], v + l, a->i[row + 1] - a->i[row]));
519:     PetscCall(MatSeqAIJRestoreArray(mat->A, &aa));
520:   }

522:   /* right of diagonal part */
523:   if (b->i[row + 1] - b->i[row] - l) {
524:     PetscCall(MatSeqAIJGetArray(mat->B, &ba));
525:     PetscCall(PetscArraycpy(ba + b->i[row] + l, v + l + a->i[row + 1] - a->i[row], b->i[row + 1] - b->i[row] - l));
526:     PetscCall(MatSeqAIJRestoreArray(mat->B, &ba));
527:   }
528:   PetscFunctionReturn(PETSC_SUCCESS);
529: }

531: PetscErrorCode MatSetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt im[], PetscInt n, const PetscInt in[], const PetscScalar v[], InsertMode addv)
532: {
533:   Mat_MPIAIJ *aij   = (Mat_MPIAIJ *)mat->data;
534:   PetscScalar value = 0.0;
535:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
536:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
537:   PetscBool   roworiented = aij->roworiented;

539:   /* Some Variables required in the macro */
540:   Mat         A     = aij->A;
541:   Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
542:   PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
543:   PetscBool   ignorezeroentries = a->ignorezeroentries;
544:   Mat         B                 = aij->B;
545:   Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
546:   PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
547:   MatScalar  *aa, *ba;
548:   PetscInt   *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
549:   PetscInt    nonew;
550:   MatScalar  *ap1, *ap2;

552:   PetscFunctionBegin;
553:   PetscCall(MatSeqAIJGetArray(A, &aa));
554:   PetscCall(MatSeqAIJGetArray(B, &ba));
555:   for (i = 0; i < m; i++) {
556:     if (im[i] < 0) continue;
557:     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);
558:     if (im[i] >= rstart && im[i] < rend) {
559:       row      = im[i] - rstart;
560:       lastcol1 = -1;
561:       rp1      = PetscSafePointerPlusOffset(aj, ai[row]);
562:       ap1      = PetscSafePointerPlusOffset(aa, ai[row]);
563:       rmax1    = aimax[row];
564:       nrow1    = ailen[row];
565:       low1     = 0;
566:       high1    = nrow1;
567:       lastcol2 = -1;
568:       rp2      = PetscSafePointerPlusOffset(bj, bi[row]);
569:       ap2      = PetscSafePointerPlusOffset(ba, bi[row]);
570:       rmax2    = bimax[row];
571:       nrow2    = bilen[row];
572:       low2     = 0;
573:       high2    = nrow2;

575:       for (j = 0; j < n; j++) {
576:         if (v) value = roworiented ? v[i * n + j] : v[i + j * m];
577:         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
578:         if (in[j] >= cstart && in[j] < cend) {
579:           col   = in[j] - cstart;
580:           nonew = a->nonew;
581:           MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
582:         } else if (in[j] < 0) {
583:           continue;
584:         } else {
585:           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);
586:           if (mat->was_assembled) {
587:             if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
588: #if defined(PETSC_USE_CTABLE)
589:             PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col)); /* map global col ids to local ones */
590:             col--;
591: #else
592:             col = aij->colmap[in[j]] - 1;
593: #endif
594:             if (col < 0 && !((Mat_SeqAIJ *)aij->B->data)->nonew) { /* col < 0 means in[j] is a new col for B */
595:               PetscCall(MatDisAssemble_MPIAIJ(mat));               /* Change aij->B from reduced/local format to expanded/global format */
596:               col = in[j];
597:               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
598:               B     = aij->B;
599:               b     = (Mat_SeqAIJ *)B->data;
600:               bimax = b->imax;
601:               bi    = b->i;
602:               bilen = b->ilen;
603:               bj    = b->j;
604:               ba    = b->a;
605:               rp2   = PetscSafePointerPlusOffset(bj, bi[row]);
606:               ap2   = PetscSafePointerPlusOffset(ba, bi[row]);
607:               rmax2 = bimax[row];
608:               nrow2 = bilen[row];
609:               low2  = 0;
610:               high2 = nrow2;
611:               bm    = aij->B->rmap->n;
612:               ba    = b->a;
613:             } else if (col < 0 && !(ignorezeroentries && value == 0.0)) {
614:               if (1 == ((Mat_SeqAIJ *)aij->B->data)->nonew) {
615:                 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]));
616:               } else SETERRQ(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]);
617:             }
618:           } else col = in[j];
619:           nonew = b->nonew;
620:           MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
621:         }
622:       }
623:     } else {
624:       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]);
625:       if (!aij->donotstash) {
626:         mat->assembled = PETSC_FALSE;
627:         if (roworiented) {
628:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i * n), (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
629:         } else {
630:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, PetscSafePointerPlusOffset(v, i), m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
631:         }
632:       }
633:     }
634:   }
635:   PetscCall(MatSeqAIJRestoreArray(A, &aa)); /* aa, bb might have been free'd due to reallocation above. But we don't access them here */
636:   PetscCall(MatSeqAIJRestoreArray(B, &ba));
637:   PetscFunctionReturn(PETSC_SUCCESS);
638: }

640: /*
641:     This function sets the j and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
642:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
643:     No off-processor parts off the matrix are allowed here and mat->was_assembled has to be PETSC_FALSE.
644: */
645: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat_Symbolic(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[])
646: {
647:   Mat_MPIAIJ *aij    = (Mat_MPIAIJ *)mat->data;
648:   Mat         A      = aij->A; /* diagonal part of the matrix */
649:   Mat         B      = aij->B; /* off-diagonal part of the matrix */
650:   Mat_SeqAIJ *a      = (Mat_SeqAIJ *)A->data;
651:   Mat_SeqAIJ *b      = (Mat_SeqAIJ *)B->data;
652:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, col;
653:   PetscInt   *ailen = a->ilen, *aj = a->j;
654:   PetscInt   *bilen = b->ilen, *bj = b->j;
655:   PetscInt    am          = aij->A->rmap->n, j;
656:   PetscInt    diag_so_far = 0, dnz;
657:   PetscInt    offd_so_far = 0, onz;

659:   PetscFunctionBegin;
660:   /* Iterate over all rows of the matrix */
661:   for (j = 0; j < am; j++) {
662:     dnz = onz = 0;
663:     /*  Iterate over all non-zero columns of the current row */
664:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
665:       /* If column is in the diagonal */
666:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
667:         aj[diag_so_far++] = mat_j[col] - cstart;
668:         dnz++;
669:       } else { /* off-diagonal entries */
670:         bj[offd_so_far++] = mat_j[col];
671:         onz++;
672:       }
673:     }
674:     ailen[j] = dnz;
675:     bilen[j] = onz;
676:   }
677:   PetscFunctionReturn(PETSC_SUCCESS);
678: }

680: /*
681:     This function sets the local j, a and ilen arrays (of the diagonal and off-diagonal part) of an MPIAIJ-matrix.
682:     The values in mat_i have to be sorted and the values in mat_j have to be sorted for each row (CSR-like).
683:     No off-processor parts off the matrix are allowed here, they are set at a later point by MatSetValues_MPIAIJ.
684:     Also, mat->was_assembled has to be false, otherwise the statement aj[rowstart_diag+dnz_row] = mat_j[col] - cstart;
685:     would not be true and the more complex MatSetValues_MPIAIJ has to be used.
686: */
687: PetscErrorCode MatSetValues_MPIAIJ_CopyFromCSRFormat(Mat mat, const PetscInt mat_j[], const PetscInt mat_i[], const PetscScalar mat_a[])
688: {
689:   Mat_MPIAIJ  *aij  = (Mat_MPIAIJ *)mat->data;
690:   Mat          A    = aij->A; /* diagonal part of the matrix */
691:   Mat          B    = aij->B; /* off-diagonal part of the matrix */
692:   Mat_SeqAIJ  *aijd = (Mat_SeqAIJ *)aij->A->data, *aijo = (Mat_SeqAIJ *)aij->B->data;
693:   Mat_SeqAIJ  *a      = (Mat_SeqAIJ *)A->data;
694:   Mat_SeqAIJ  *b      = (Mat_SeqAIJ *)B->data;
695:   PetscInt     cstart = mat->cmap->rstart, cend = mat->cmap->rend;
696:   PetscInt    *ailen = a->ilen, *aj = a->j;
697:   PetscInt    *bilen = b->ilen, *bj = b->j;
698:   PetscInt     am          = aij->A->rmap->n, j;
699:   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. */
700:   PetscInt     col, dnz_row, onz_row, rowstart_diag, rowstart_offd;
701:   PetscScalar *aa = a->a, *ba = b->a;

703:   PetscFunctionBegin;
704:   /* Iterate over all rows of the matrix */
705:   for (j = 0; j < am; j++) {
706:     dnz_row = onz_row = 0;
707:     rowstart_offd     = full_offd_i[j];
708:     rowstart_diag     = full_diag_i[j];
709:     /*  Iterate over all non-zero columns of the current row */
710:     for (col = mat_i[j]; col < mat_i[j + 1]; col++) {
711:       /* If column is in the diagonal */
712:       if (mat_j[col] >= cstart && mat_j[col] < cend) {
713:         aj[rowstart_diag + dnz_row] = mat_j[col] - cstart;
714:         aa[rowstart_diag + dnz_row] = mat_a[col];
715:         dnz_row++;
716:       } else { /* off-diagonal entries */
717:         bj[rowstart_offd + onz_row] = mat_j[col];
718:         ba[rowstart_offd + onz_row] = mat_a[col];
719:         onz_row++;
720:       }
721:     }
722:     ailen[j] = dnz_row;
723:     bilen[j] = onz_row;
724:   }
725:   PetscFunctionReturn(PETSC_SUCCESS);
726: }

728: static PetscErrorCode MatGetValues_MPIAIJ(Mat mat, PetscInt m, const PetscInt idxm[], PetscInt n, const PetscInt idxn[], PetscScalar v[])
729: {
730:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
731:   PetscInt    i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
732:   PetscInt    cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;

734:   PetscFunctionBegin;
735:   for (i = 0; i < m; i++) {
736:     if (idxm[i] < 0) continue; /* negative row */
737:     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);
738:     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);
739:     row = idxm[i] - rstart;
740:     for (j = 0; j < n; j++) {
741:       if (idxn[j] < 0) continue; /* negative column */
742:       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);
743:       if (idxn[j] >= cstart && idxn[j] < cend) {
744:         col = idxn[j] - cstart;
745:         PetscCall(MatGetValues(aij->A, 1, &row, 1, &col, v + i * n + j));
746:       } else {
747:         if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
748: #if defined(PETSC_USE_CTABLE)
749:         PetscCall(PetscHMapIGetWithDefault(aij->colmap, idxn[j] + 1, 0, &col));
750:         col--;
751: #else
752:         col = aij->colmap[idxn[j]] - 1;
753: #endif
754:         if ((col < 0) || (aij->garray[col] != idxn[j])) *(v + i * n + j) = 0.0;
755:         else PetscCall(MatGetValues(aij->B, 1, &row, 1, &col, v + i * n + j));
756:       }
757:     }
758:   }
759:   PetscFunctionReturn(PETSC_SUCCESS);
760: }

762: static PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat, MatAssemblyType mode)
763: {
764:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
765:   PetscInt    nstash, reallocs;

767:   PetscFunctionBegin;
768:   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(PETSC_SUCCESS);

770:   PetscCall(MatStashScatterBegin_Private(mat, &mat->stash, mat->rmap->range));
771:   PetscCall(MatStashGetInfo_Private(&mat->stash, &nstash, &reallocs));
772:   PetscCall(PetscInfo(aij->A, "Stash has %" PetscInt_FMT " entries, uses %" PetscInt_FMT " mallocs.\n", nstash, reallocs));
773:   PetscFunctionReturn(PETSC_SUCCESS);
774: }

776: PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat, MatAssemblyType mode)
777: {
778:   Mat_MPIAIJ  *aij = (Mat_MPIAIJ *)mat->data;
779:   PetscMPIInt  n;
780:   PetscInt     i, j, rstart, ncols, flg;
781:   PetscInt    *row, *col;
782:   PetscBool    other_disassembled;
783:   PetscScalar *val;

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

787:   PetscFunctionBegin;
788:   if (!aij->donotstash && !mat->nooffprocentries) {
789:     while (1) {
790:       PetscCall(MatStashScatterGetMesg_Private(&mat->stash, &n, &row, &col, &val, &flg));
791:       if (!flg) break;

793:       for (i = 0; i < n;) {
794:         /* Now identify the consecutive vals belonging to the same row */
795:         for (j = i, rstart = row[j]; j < n; j++) {
796:           if (row[j] != rstart) break;
797:         }
798:         if (j < n) ncols = j - i;
799:         else ncols = n - i;
800:         /* Now assemble all these values with a single function call */
801:         PetscCall(MatSetValues_MPIAIJ(mat, 1, row + i, ncols, col + i, val + i, mat->insertmode));
802:         i = j;
803:       }
804:     }
805:     PetscCall(MatStashScatterEnd_Private(&mat->stash));
806:   }
807: #if defined(PETSC_HAVE_DEVICE)
808:   if (mat->offloadmask == PETSC_OFFLOAD_CPU) aij->A->offloadmask = PETSC_OFFLOAD_CPU;
809:   /* We call MatBindToCPU() on aij->A and aij->B here, because if MatBindToCPU_MPIAIJ() is called before assembly, it cannot bind these. */
810:   if (mat->boundtocpu) {
811:     PetscCall(MatBindToCPU(aij->A, PETSC_TRUE));
812:     PetscCall(MatBindToCPU(aij->B, PETSC_TRUE));
813:   }
814: #endif
815:   PetscCall(MatAssemblyBegin(aij->A, mode));
816:   PetscCall(MatAssemblyEnd(aij->A, mode));

818:   /* determine if any processor has disassembled, if so we must
819:      also disassemble ourself, in order that we may reassemble. */
820:   /*
821:      if nonzero structure of submatrix B cannot change then we know that
822:      no processor disassembled thus we can skip this stuff
823:   */
824:   if (!((Mat_SeqAIJ *)aij->B->data)->nonew) {
825:     PetscCallMPI(MPIU_Allreduce(&mat->was_assembled, &other_disassembled, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
826:     if (mat->was_assembled && !other_disassembled) { /* mat on this rank has reduced off-diag B with local col ids, but globally it does not */
827:       PetscCall(MatDisAssemble_MPIAIJ(mat));
828:     }
829:   }
830:   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) PetscCall(MatSetUpMultiply_MPIAIJ(mat));
831:   PetscCall(MatSetOption(aij->B, MAT_USE_INODES, PETSC_FALSE));
832: #if defined(PETSC_HAVE_DEVICE)
833:   if (mat->offloadmask == PETSC_OFFLOAD_CPU && aij->B->offloadmask != PETSC_OFFLOAD_UNALLOCATED) aij->B->offloadmask = PETSC_OFFLOAD_CPU;
834: #endif
835:   PetscCall(MatAssemblyBegin(aij->B, mode));
836:   PetscCall(MatAssemblyEnd(aij->B, mode));

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

840:   aij->rowvalues = NULL;

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

844:   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
845:   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ *)aij->A->data)->nonew) {
846:     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
847:     PetscCallMPI(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));
848:   }
849: #if defined(PETSC_HAVE_DEVICE)
850:   mat->offloadmask = PETSC_OFFLOAD_BOTH;
851: #endif
852:   PetscFunctionReturn(PETSC_SUCCESS);
853: }

855: static PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
856: {
857:   Mat_MPIAIJ *l = (Mat_MPIAIJ *)A->data;

859:   PetscFunctionBegin;
860:   PetscCall(MatZeroEntries(l->A));
861:   PetscCall(MatZeroEntries(l->B));
862:   PetscFunctionReturn(PETSC_SUCCESS);
863: }

865: static PetscErrorCode MatZeroRows_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
866: {
867:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)A->data;
868:   PetscInt   *lrows;
869:   PetscInt    r, len;
870:   PetscBool   cong;

872:   PetscFunctionBegin;
873:   /* get locally owned rows */
874:   PetscCall(MatZeroRowsMapLocal_Private(A, N, rows, &len, &lrows));
875:   PetscCall(MatHasCongruentLayouts(A, &cong));
876:   /* fix right-hand side if needed */
877:   if (x && b) {
878:     const PetscScalar *xx;
879:     PetscScalar       *bb;

881:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
882:     PetscCall(VecGetArrayRead(x, &xx));
883:     PetscCall(VecGetArray(b, &bb));
884:     for (r = 0; r < len; ++r) bb[lrows[r]] = diag * xx[lrows[r]];
885:     PetscCall(VecRestoreArrayRead(x, &xx));
886:     PetscCall(VecRestoreArray(b, &bb));
887:   }

889:   if (diag != 0.0 && cong) {
890:     PetscCall(MatZeroRows(mat->A, len, lrows, diag, NULL, NULL));
891:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
892:   } else if (diag != 0.0) { /* non-square or non congruent layouts -> if keepnonzeropattern is false, we allow for new insertion */
893:     Mat_SeqAIJ *aijA = (Mat_SeqAIJ *)mat->A->data;
894:     Mat_SeqAIJ *aijB = (Mat_SeqAIJ *)mat->B->data;
895:     PetscInt    nnwA, nnwB;
896:     PetscBool   nnzA, nnzB;

898:     nnwA = aijA->nonew;
899:     nnwB = aijB->nonew;
900:     nnzA = aijA->keepnonzeropattern;
901:     nnzB = aijB->keepnonzeropattern;
902:     if (!nnzA) {
903:       PetscCall(PetscInfo(mat->A, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on diagonal block.\n"));
904:       aijA->nonew = 0;
905:     }
906:     if (!nnzB) {
907:       PetscCall(PetscInfo(mat->B, "Requested to not keep the pattern and add a nonzero diagonal; may encounter reallocations on off-diagonal block.\n"));
908:       aijB->nonew = 0;
909:     }
910:     /* Must zero here before the next loop */
911:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
912:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
913:     for (r = 0; r < len; ++r) {
914:       const PetscInt row = lrows[r] + A->rmap->rstart;
915:       if (row >= A->cmap->N) continue;
916:       PetscCall(MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES));
917:     }
918:     aijA->nonew = nnwA;
919:     aijB->nonew = nnwB;
920:   } else {
921:     PetscCall(MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL));
922:     PetscCall(MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL));
923:   }
924:   PetscCall(PetscFree(lrows));
925:   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
926:   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

928:   /* only change matrix nonzero state if pattern was allowed to be changed */
929:   if (!((Mat_SeqAIJ *)mat->A->data)->keepnonzeropattern || !((Mat_SeqAIJ *)mat->A->data)->nonew) {
930:     PetscObjectState state = mat->A->nonzerostate + mat->B->nonzerostate;
931:     PetscCallMPI(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
932:   }
933:   PetscFunctionReturn(PETSC_SUCCESS);
934: }

936: static PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A, PetscInt N, const PetscInt rows[], PetscScalar diag, Vec x, Vec b)
937: {
938:   Mat_MPIAIJ        *l = (Mat_MPIAIJ *)A->data;
939:   PetscInt           n = A->rmap->n;
940:   PetscInt           i, j, r, m, len = 0;
941:   PetscInt          *lrows, *owners = A->rmap->range;
942:   PetscMPIInt        p = 0;
943:   PetscSFNode       *rrows;
944:   PetscSF            sf;
945:   const PetscScalar *xx;
946:   PetscScalar       *bb, *mask, *aij_a;
947:   Vec                xmask, lmask;
948:   Mat_SeqAIJ        *aij = (Mat_SeqAIJ *)l->B->data;
949:   const PetscInt    *aj, *ii, *ridx;
950:   PetscScalar       *aa;

952:   PetscFunctionBegin;
953:   /* Create SF where leaves are input rows and roots are owned rows */
954:   PetscCall(PetscMalloc1(n, &lrows));
955:   for (r = 0; r < n; ++r) lrows[r] = -1;
956:   PetscCall(PetscMalloc1(N, &rrows));
957:   for (r = 0; r < N; ++r) {
958:     const PetscInt idx = rows[r];
959:     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);
960:     if (idx < owners[p] || owners[p + 1] <= idx) { /* short-circuit the search if the last p owns this row too */
961:       PetscCall(PetscLayoutFindOwner(A->rmap, idx, &p));
962:     }
963:     rrows[r].rank  = p;
964:     rrows[r].index = rows[r] - owners[p];
965:   }
966:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
967:   PetscCall(PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER));
968:   /* Collect flags for rows to be zeroed */
969:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
970:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *)rows, lrows, MPI_LOR));
971:   PetscCall(PetscSFDestroy(&sf));
972:   /* Compress and put in row numbers */
973:   for (r = 0; r < n; ++r)
974:     if (lrows[r] >= 0) lrows[len++] = r;
975:   /* zero diagonal part of matrix */
976:   PetscCall(MatZeroRowsColumns(l->A, len, lrows, diag, x, b));
977:   /* handle off-diagonal part of matrix */
978:   PetscCall(MatCreateVecs(A, &xmask, NULL));
979:   PetscCall(VecDuplicate(l->lvec, &lmask));
980:   PetscCall(VecGetArray(xmask, &bb));
981:   for (i = 0; i < len; i++) bb[lrows[i]] = 1;
982:   PetscCall(VecRestoreArray(xmask, &bb));
983:   PetscCall(VecScatterBegin(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
984:   PetscCall(VecScatterEnd(l->Mvctx, xmask, lmask, ADD_VALUES, SCATTER_FORWARD));
985:   PetscCall(VecDestroy(&xmask));
986:   if (x && b) { /* this code is buggy when the row and column layout don't match */
987:     PetscBool cong;

989:     PetscCall(MatHasCongruentLayouts(A, &cong));
990:     PetscCheck(cong, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Need matching row/col layout");
991:     PetscCall(VecScatterBegin(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
992:     PetscCall(VecScatterEnd(l->Mvctx, x, l->lvec, INSERT_VALUES, SCATTER_FORWARD));
993:     PetscCall(VecGetArrayRead(l->lvec, &xx));
994:     PetscCall(VecGetArray(b, &bb));
995:   }
996:   PetscCall(VecGetArray(lmask, &mask));
997:   /* remove zeroed rows of off-diagonal matrix */
998:   PetscCall(MatSeqAIJGetArray(l->B, &aij_a));
999:   ii = aij->i;
1000:   for (i = 0; i < len; i++) PetscCall(PetscArrayzero(PetscSafePointerPlusOffset(aij_a, ii[lrows[i]]), ii[lrows[i] + 1] - ii[lrows[i]]));
1001:   /* loop over all elements of off process part of matrix zeroing removed columns*/
1002:   if (aij->compressedrow.use) {
1003:     m    = aij->compressedrow.nrows;
1004:     ii   = aij->compressedrow.i;
1005:     ridx = aij->compressedrow.rindex;
1006:     for (i = 0; i < m; i++) {
1007:       n  = ii[i + 1] - ii[i];
1008:       aj = aij->j + ii[i];
1009:       aa = aij_a + ii[i];

1011:       for (j = 0; j < n; j++) {
1012:         if (PetscAbsScalar(mask[*aj])) {
1013:           if (b) bb[*ridx] -= *aa * xx[*aj];
1014:           *aa = 0.0;
1015:         }
1016:         aa++;
1017:         aj++;
1018:       }
1019:       ridx++;
1020:     }
1021:   } else { /* do not use compressed row format */
1022:     m = l->B->rmap->n;
1023:     for (i = 0; i < m; i++) {
1024:       n  = ii[i + 1] - ii[i];
1025:       aj = aij->j + ii[i];
1026:       aa = aij_a + ii[i];
1027:       for (j = 0; j < n; j++) {
1028:         if (PetscAbsScalar(mask[*aj])) {
1029:           if (b) bb[i] -= *aa * xx[*aj];
1030:           *aa = 0.0;
1031:         }
1032:         aa++;
1033:         aj++;
1034:       }
1035:     }
1036:   }
1037:   if (x && b) {
1038:     PetscCall(VecRestoreArray(b, &bb));
1039:     PetscCall(VecRestoreArrayRead(l->lvec, &xx));
1040:   }
1041:   PetscCall(MatSeqAIJRestoreArray(l->B, &aij_a));
1042:   PetscCall(VecRestoreArray(lmask, &mask));
1043:   PetscCall(VecDestroy(&lmask));
1044:   PetscCall(PetscFree(lrows));

1046:   /* only change matrix nonzero state if pattern was allowed to be changed */
1047:   if (!((Mat_SeqAIJ *)l->A->data)->nonew) {
1048:     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
1049:     PetscCallMPI(MPIU_Allreduce(&state, &A->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)A)));
1050:   }
1051:   PetscFunctionReturn(PETSC_SUCCESS);
1052: }

1054: static PetscErrorCode MatMult_MPIAIJ(Mat A, Vec xx, Vec yy)
1055: {
1056:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
1057:   PetscInt    nt;
1058:   VecScatter  Mvctx = a->Mvctx;

1060:   PetscFunctionBegin;
1061:   PetscCall(VecGetLocalSize(xx, &nt));
1062:   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);
1063:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1064:   PetscUseTypeMethod(a->A, mult, xx, yy);
1065:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1066:   PetscUseTypeMethod(a->B, multadd, a->lvec, yy, yy);
1067:   PetscFunctionReturn(PETSC_SUCCESS);
1068: }

1070: static PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A, Vec bb, Vec xx)
1071: {
1072:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1074:   PetscFunctionBegin;
1075:   PetscCall(MatMultDiagonalBlock(a->A, bb, xx));
1076:   PetscFunctionReturn(PETSC_SUCCESS);
1077: }

1079: static PetscErrorCode MatMultAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1080: {
1081:   Mat_MPIAIJ *a     = (Mat_MPIAIJ *)A->data;
1082:   VecScatter  Mvctx = a->Mvctx;

1084:   PetscFunctionBegin;
1085:   PetscCall(VecScatterBegin(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1086:   PetscCall((*a->A->ops->multadd)(a->A, xx, yy, zz));
1087:   PetscCall(VecScatterEnd(Mvctx, xx, a->lvec, INSERT_VALUES, SCATTER_FORWARD));
1088:   PetscCall((*a->B->ops->multadd)(a->B, a->lvec, zz, zz));
1089:   PetscFunctionReturn(PETSC_SUCCESS);
1090: }

1092: static PetscErrorCode MatMultTranspose_MPIAIJ(Mat A, Vec xx, Vec yy)
1093: {
1094:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1096:   PetscFunctionBegin;
1097:   /* do nondiagonal part */
1098:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1099:   /* do local part */
1100:   PetscCall((*a->A->ops->multtranspose)(a->A, xx, yy));
1101:   /* add partial results together */
1102:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1103:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, yy, ADD_VALUES, SCATTER_REVERSE));
1104:   PetscFunctionReturn(PETSC_SUCCESS);
1105: }

1107: static PetscErrorCode MatIsTranspose_MPIAIJ(Mat Amat, Mat Bmat, PetscReal tol, PetscBool *f)
1108: {
1109:   MPI_Comm    comm;
1110:   Mat_MPIAIJ *Aij = (Mat_MPIAIJ *)Amat->data, *Bij = (Mat_MPIAIJ *)Bmat->data;
1111:   Mat         Adia = Aij->A, Bdia = Bij->A, Aoff, Boff, *Aoffs, *Boffs;
1112:   IS          Me, Notme;
1113:   PetscInt    M, N, first, last, *notme, i;
1114:   PetscBool   lf;
1115:   PetscMPIInt size;

1117:   PetscFunctionBegin;
1118:   /* Easy test: symmetric diagonal block */
1119:   PetscCall(MatIsTranspose(Adia, Bdia, tol, &lf));
1120:   PetscCallMPI(MPIU_Allreduce(&lf, f, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)Amat)));
1121:   if (!*f) PetscFunctionReturn(PETSC_SUCCESS);
1122:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
1123:   PetscCallMPI(MPI_Comm_size(comm, &size));
1124:   if (size == 1) PetscFunctionReturn(PETSC_SUCCESS);

1126:   /* Hard test: off-diagonal block. This takes a MatCreateSubMatrix. */
1127:   PetscCall(MatGetSize(Amat, &M, &N));
1128:   PetscCall(MatGetOwnershipRange(Amat, &first, &last));
1129:   PetscCall(PetscMalloc1(N - last + first, &notme));
1130:   for (i = 0; i < first; i++) notme[i] = i;
1131:   for (i = last; i < M; i++) notme[i - last + first] = i;
1132:   PetscCall(ISCreateGeneral(MPI_COMM_SELF, N - last + first, notme, PETSC_COPY_VALUES, &Notme));
1133:   PetscCall(ISCreateStride(MPI_COMM_SELF, last - first, first, 1, &Me));
1134:   PetscCall(MatCreateSubMatrices(Amat, 1, &Me, &Notme, MAT_INITIAL_MATRIX, &Aoffs));
1135:   Aoff = Aoffs[0];
1136:   PetscCall(MatCreateSubMatrices(Bmat, 1, &Notme, &Me, MAT_INITIAL_MATRIX, &Boffs));
1137:   Boff = Boffs[0];
1138:   PetscCall(MatIsTranspose(Aoff, Boff, tol, f));
1139:   PetscCall(MatDestroyMatrices(1, &Aoffs));
1140:   PetscCall(MatDestroyMatrices(1, &Boffs));
1141:   PetscCall(ISDestroy(&Me));
1142:   PetscCall(ISDestroy(&Notme));
1143:   PetscCall(PetscFree(notme));
1144:   PetscFunctionReturn(PETSC_SUCCESS);
1145: }

1147: static PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A, Vec xx, Vec yy, Vec zz)
1148: {
1149:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1151:   PetscFunctionBegin;
1152:   /* do nondiagonal part */
1153:   PetscCall((*a->B->ops->multtranspose)(a->B, xx, a->lvec));
1154:   /* do local part */
1155:   PetscCall((*a->A->ops->multtransposeadd)(a->A, xx, yy, zz));
1156:   /* add partial results together */
1157:   PetscCall(VecScatterBegin(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1158:   PetscCall(VecScatterEnd(a->Mvctx, a->lvec, zz, ADD_VALUES, SCATTER_REVERSE));
1159:   PetscFunctionReturn(PETSC_SUCCESS);
1160: }

1162: /*
1163:   This only works correctly for square matrices where the subblock A->A is the
1164:    diagonal block
1165: */
1166: static PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A, Vec v)
1167: {
1168:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1170:   PetscFunctionBegin;
1171:   PetscCheck(A->rmap->N == A->cmap->N, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Supports only square matrix where A->A is diag block");
1172:   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");
1173:   PetscCall(MatGetDiagonal(a->A, v));
1174:   PetscFunctionReturn(PETSC_SUCCESS);
1175: }

1177: static PetscErrorCode MatScale_MPIAIJ(Mat A, PetscScalar aa)
1178: {
1179:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1181:   PetscFunctionBegin;
1182:   PetscCall(MatScale(a->A, aa));
1183:   PetscCall(MatScale(a->B, aa));
1184:   PetscFunctionReturn(PETSC_SUCCESS);
1185: }

1187: static PetscErrorCode MatView_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
1188: {
1189:   Mat_MPIAIJ        *aij    = (Mat_MPIAIJ *)mat->data;
1190:   Mat_SeqAIJ        *A      = (Mat_SeqAIJ *)aij->A->data;
1191:   Mat_SeqAIJ        *B      = (Mat_SeqAIJ *)aij->B->data;
1192:   const PetscInt    *garray = aij->garray;
1193:   const PetscScalar *aa, *ba;
1194:   PetscInt           header[4], M, N, m, rs, cs, cnt, i, ja, jb;
1195:   PetscInt64         nz, hnz;
1196:   PetscInt          *rowlens;
1197:   PetscInt          *colidxs;
1198:   PetscScalar       *matvals;
1199:   PetscMPIInt        rank;

1201:   PetscFunctionBegin;
1202:   PetscCall(PetscViewerSetUp(viewer));

1204:   M  = mat->rmap->N;
1205:   N  = mat->cmap->N;
1206:   m  = mat->rmap->n;
1207:   rs = mat->rmap->rstart;
1208:   cs = mat->cmap->rstart;
1209:   nz = A->nz + B->nz;

1211:   /* write matrix header */
1212:   header[0] = MAT_FILE_CLASSID;
1213:   header[1] = M;
1214:   header[2] = N;
1215:   PetscCallMPI(MPI_Reduce(&nz, &hnz, 1, MPIU_INT64, MPI_SUM, 0, PetscObjectComm((PetscObject)mat)));
1216:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1217:   if (rank == 0) PetscCall(PetscIntCast(hnz, &header[3]));
1218:   PetscCall(PetscViewerBinaryWrite(viewer, header, 4, PETSC_INT));

1220:   /* fill in and store row lengths  */
1221:   PetscCall(PetscMalloc1(m, &rowlens));
1222:   for (i = 0; i < m; i++) rowlens[i] = A->i[i + 1] - A->i[i] + B->i[i + 1] - B->i[i];
1223:   PetscCall(PetscViewerBinaryWriteAll(viewer, rowlens, m, rs, M, PETSC_INT));
1224:   PetscCall(PetscFree(rowlens));

1226:   /* fill in and store column indices */
1227:   PetscCall(PetscMalloc1(nz, &colidxs));
1228:   for (cnt = 0, i = 0; i < m; i++) {
1229:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1230:       if (garray[B->j[jb]] > cs) break;
1231:       colidxs[cnt++] = garray[B->j[jb]];
1232:     }
1233:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) colidxs[cnt++] = A->j[ja] + cs;
1234:     for (; jb < B->i[i + 1]; jb++) colidxs[cnt++] = garray[B->j[jb]];
1235:   }
1236:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1237:   PetscCall(PetscViewerBinaryWriteAll(viewer, colidxs, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
1238:   PetscCall(PetscFree(colidxs));

1240:   /* fill in and store nonzero values */
1241:   PetscCall(MatSeqAIJGetArrayRead(aij->A, &aa));
1242:   PetscCall(MatSeqAIJGetArrayRead(aij->B, &ba));
1243:   PetscCall(PetscMalloc1(nz, &matvals));
1244:   for (cnt = 0, i = 0; i < m; i++) {
1245:     for (jb = B->i[i]; jb < B->i[i + 1]; jb++) {
1246:       if (garray[B->j[jb]] > cs) break;
1247:       matvals[cnt++] = ba[jb];
1248:     }
1249:     for (ja = A->i[i]; ja < A->i[i + 1]; ja++) matvals[cnt++] = aa[ja];
1250:     for (; jb < B->i[i + 1]; jb++) matvals[cnt++] = ba[jb];
1251:   }
1252:   PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &aa));
1253:   PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &ba));
1254:   PetscCheck(cnt == nz, PETSC_COMM_SELF, PETSC_ERR_LIB, "Internal PETSc error: cnt = %" PetscInt_FMT " nz = %" PetscInt64_FMT, cnt, nz);
1255:   PetscCall(PetscViewerBinaryWriteAll(viewer, matvals, nz, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
1256:   PetscCall(PetscFree(matvals));

1258:   /* write block size option to the viewer's .info file */
1259:   PetscCall(MatView_Binary_BlockSizes(mat, viewer));
1260:   PetscFunctionReturn(PETSC_SUCCESS);
1261: }

1263: #include <petscdraw.h>
1264: static PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat, PetscViewer viewer)
1265: {
1266:   Mat_MPIAIJ       *aij  = (Mat_MPIAIJ *)mat->data;
1267:   PetscMPIInt       rank = aij->rank, size = aij->size;
1268:   PetscBool         isdraw, iascii, isbinary;
1269:   PetscViewer       sviewer;
1270:   PetscViewerFormat format;

1272:   PetscFunctionBegin;
1273:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1274:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
1275:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1276:   if (iascii) {
1277:     PetscCall(PetscViewerGetFormat(viewer, &format));
1278:     if (format == PETSC_VIEWER_LOAD_BALANCE) {
1279:       PetscInt i, nmax = 0, nmin = PETSC_INT_MAX, navg = 0, *nz, nzlocal = ((Mat_SeqAIJ *)aij->A->data)->nz + ((Mat_SeqAIJ *)aij->B->data)->nz;
1280:       PetscCall(PetscMalloc1(size, &nz));
1281:       PetscCallMPI(MPI_Allgather(&nzlocal, 1, MPIU_INT, nz, 1, MPIU_INT, PetscObjectComm((PetscObject)mat)));
1282:       for (i = 0; i < size; i++) {
1283:         nmax = PetscMax(nmax, nz[i]);
1284:         nmin = PetscMin(nmin, nz[i]);
1285:         navg += nz[i];
1286:       }
1287:       PetscCall(PetscFree(nz));
1288:       navg = navg / size;
1289:       PetscCall(PetscViewerASCIIPrintf(viewer, "Load Balance - Nonzeros: Min %" PetscInt_FMT "  avg %" PetscInt_FMT "  max %" PetscInt_FMT "\n", nmin, navg, nmax));
1290:       PetscFunctionReturn(PETSC_SUCCESS);
1291:     }
1292:     PetscCall(PetscViewerGetFormat(viewer, &format));
1293:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1294:       MatInfo   info;
1295:       PetscInt *inodes = NULL;

1297:       PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)mat), &rank));
1298:       PetscCall(MatGetInfo(mat, MAT_LOCAL, &info));
1299:       PetscCall(MatInodeGetInodeSizes(aij->A, NULL, &inodes, NULL));
1300:       PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1301:       if (!inodes) {
1302:         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,
1303:                                                      info.memory));
1304:       } else {
1305:         PetscCall(
1306:           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));
1307:       }
1308:       PetscCall(MatGetInfo(aij->A, MAT_LOCAL, &info));
1309:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] on-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1310:       PetscCall(MatGetInfo(aij->B, MAT_LOCAL, &info));
1311:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "[%d] off-diagonal part: nz %" PetscInt_FMT " \n", rank, (PetscInt)info.nz_used));
1312:       PetscCall(PetscViewerFlush(viewer));
1313:       PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1314:       PetscCall(PetscViewerASCIIPrintf(viewer, "Information on VecScatter used in matrix-vector product: \n"));
1315:       PetscCall(VecScatterView(aij->Mvctx, viewer));
1316:       PetscFunctionReturn(PETSC_SUCCESS);
1317:     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1318:       PetscInt inodecount, inodelimit, *inodes;
1319:       PetscCall(MatInodeGetInodeSizes(aij->A, &inodecount, &inodes, &inodelimit));
1320:       if (inodes) {
1321:         PetscCall(PetscViewerASCIIPrintf(viewer, "using I-node (on process 0) routines: found %" PetscInt_FMT " nodes, limit used is %" PetscInt_FMT "\n", inodecount, inodelimit));
1322:       } else {
1323:         PetscCall(PetscViewerASCIIPrintf(viewer, "not using I-node (on process 0) routines\n"));
1324:       }
1325:       PetscFunctionReturn(PETSC_SUCCESS);
1326:     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1327:       PetscFunctionReturn(PETSC_SUCCESS);
1328:     }
1329:   } else if (isbinary) {
1330:     if (size == 1) {
1331:       PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1332:       PetscCall(MatView(aij->A, viewer));
1333:     } else {
1334:       PetscCall(MatView_MPIAIJ_Binary(mat, viewer));
1335:     }
1336:     PetscFunctionReturn(PETSC_SUCCESS);
1337:   } else if (iascii && size == 1) {
1338:     PetscCall(PetscObjectSetName((PetscObject)aij->A, ((PetscObject)mat)->name));
1339:     PetscCall(MatView(aij->A, viewer));
1340:     PetscFunctionReturn(PETSC_SUCCESS);
1341:   } else if (isdraw) {
1342:     PetscDraw draw;
1343:     PetscBool isnull;
1344:     PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
1345:     PetscCall(PetscDrawIsNull(draw, &isnull));
1346:     if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
1347:   }

1349:   { /* assemble the entire matrix onto first processor */
1350:     Mat A = NULL, Av;
1351:     IS  isrow, iscol;

1353:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->rmap->N : 0, 0, 1, &isrow));
1354:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat), rank == 0 ? mat->cmap->N : 0, 0, 1, &iscol));
1355:     PetscCall(MatCreateSubMatrix(mat, isrow, iscol, MAT_INITIAL_MATRIX, &A));
1356:     PetscCall(MatMPIAIJGetSeqAIJ(A, &Av, NULL, NULL));
1357:     /*  The commented code uses MatCreateSubMatrices instead */
1358:     /*
1359:     Mat *AA, A = NULL, Av;
1360:     IS  isrow,iscol;

1362:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->rmap->N : 0,0,1,&isrow));
1363:     PetscCall(ISCreateStride(PetscObjectComm((PetscObject)mat),rank == 0 ? mat->cmap->N : 0,0,1,&iscol));
1364:     PetscCall(MatCreateSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&AA));
1365:     if (rank == 0) {
1366:        PetscCall(PetscObjectReference((PetscObject)AA[0]));
1367:        A    = AA[0];
1368:        Av   = AA[0];
1369:     }
1370:     PetscCall(MatDestroySubMatrices(1,&AA));
1371: */
1372:     PetscCall(ISDestroy(&iscol));
1373:     PetscCall(ISDestroy(&isrow));
1374:     /*
1375:        Everyone has to call to draw the matrix since the graphics waits are
1376:        synchronized across all processors that share the PetscDraw object
1377:     */
1378:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1379:     if (rank == 0) {
1380:       if (((PetscObject)mat)->name) PetscCall(PetscObjectSetName((PetscObject)Av, ((PetscObject)mat)->name));
1381:       PetscCall(MatView_SeqAIJ(Av, sviewer));
1382:     }
1383:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
1384:     PetscCall(MatDestroy(&A));
1385:   }
1386:   PetscFunctionReturn(PETSC_SUCCESS);
1387: }

1389: PetscErrorCode MatView_MPIAIJ(Mat mat, PetscViewer viewer)
1390: {
1391:   PetscBool iascii, isdraw, issocket, isbinary;

1393:   PetscFunctionBegin;
1394:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
1395:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
1396:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
1397:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSOCKET, &issocket));
1398:   if (iascii || isdraw || isbinary || issocket) PetscCall(MatView_MPIAIJ_ASCIIorDraworSocket(mat, viewer));
1399:   PetscFunctionReturn(PETSC_SUCCESS);
1400: }

1402: static PetscErrorCode MatSOR_MPIAIJ(Mat matin, Vec bb, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec xx)
1403: {
1404:   Mat_MPIAIJ *mat = (Mat_MPIAIJ *)matin->data;
1405:   Vec         bb1 = NULL;
1406:   PetscBool   hasop;

1408:   PetscFunctionBegin;
1409:   if (flag == SOR_APPLY_UPPER) {
1410:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1411:     PetscFunctionReturn(PETSC_SUCCESS);
1412:   }

1414:   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) PetscCall(VecDuplicate(bb, &bb1));

1416:   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1417:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1418:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1419:       its--;
1420:     }

1422:     while (its--) {
1423:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1424:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1426:       /* update rhs: bb1 = bb - B*x */
1427:       PetscCall(VecScale(mat->lvec, -1.0));
1428:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1430:       /* local sweep */
1431:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_SYMMETRIC_SWEEP, fshift, lits, 1, xx));
1432:     }
1433:   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1434:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1435:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1436:       its--;
1437:     }
1438:     while (its--) {
1439:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1440:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1442:       /* update rhs: bb1 = bb - B*x */
1443:       PetscCall(VecScale(mat->lvec, -1.0));
1444:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1446:       /* local sweep */
1447:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_FORWARD_SWEEP, fshift, lits, 1, xx));
1448:     }
1449:   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1450:     if (flag & SOR_ZERO_INITIAL_GUESS) {
1451:       PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, flag, fshift, lits, 1, xx));
1452:       its--;
1453:     }
1454:     while (its--) {
1455:       PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1456:       PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));

1458:       /* update rhs: bb1 = bb - B*x */
1459:       PetscCall(VecScale(mat->lvec, -1.0));
1460:       PetscCall((*mat->B->ops->multadd)(mat->B, mat->lvec, bb, bb1));

1462:       /* local sweep */
1463:       PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, SOR_BACKWARD_SWEEP, fshift, lits, 1, xx));
1464:     }
1465:   } else if (flag & SOR_EISENSTAT) {
1466:     Vec xx1;

1468:     PetscCall(VecDuplicate(bb, &xx1));
1469:     PetscCall((*mat->A->ops->sor)(mat->A, bb, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP), fshift, lits, 1, xx));

1471:     PetscCall(VecScatterBegin(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1472:     PetscCall(VecScatterEnd(mat->Mvctx, xx, mat->lvec, INSERT_VALUES, SCATTER_FORWARD));
1473:     if (!mat->diag) {
1474:       PetscCall(MatCreateVecs(matin, &mat->diag, NULL));
1475:       PetscCall(MatGetDiagonal(matin, mat->diag));
1476:     }
1477:     PetscCall(MatHasOperation(matin, MATOP_MULT_DIAGONAL_BLOCK, &hasop));
1478:     if (hasop) {
1479:       PetscCall(MatMultDiagonalBlock(matin, xx, bb1));
1480:     } else {
1481:       PetscCall(VecPointwiseMult(bb1, mat->diag, xx));
1482:     }
1483:     PetscCall(VecAYPX(bb1, (omega - 2.0) / omega, bb));

1485:     PetscCall(MatMultAdd(mat->B, mat->lvec, bb1, bb1));

1487:     /* local sweep */
1488:     PetscCall((*mat->A->ops->sor)(mat->A, bb1, omega, (MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP), fshift, lits, 1, xx1));
1489:     PetscCall(VecAXPY(xx, 1.0, xx1));
1490:     PetscCall(VecDestroy(&xx1));
1491:   } else SETERRQ(PetscObjectComm((PetscObject)matin), PETSC_ERR_SUP, "Parallel SOR not supported");

1493:   PetscCall(VecDestroy(&bb1));

1495:   matin->factorerrortype = mat->A->factorerrortype;
1496:   PetscFunctionReturn(PETSC_SUCCESS);
1497: }

1499: static PetscErrorCode MatPermute_MPIAIJ(Mat A, IS rowp, IS colp, Mat *B)
1500: {
1501:   Mat             aA, aB, Aperm;
1502:   const PetscInt *rwant, *cwant, *gcols, *ai, *bi, *aj, *bj;
1503:   PetscScalar    *aa, *ba;
1504:   PetscInt        i, j, m, n, ng, anz, bnz, *dnnz, *onnz, *tdnnz, *tonnz, *rdest, *cdest, *work, *gcdest;
1505:   PetscSF         rowsf, sf;
1506:   IS              parcolp = NULL;
1507:   PetscBool       done;

1509:   PetscFunctionBegin;
1510:   PetscCall(MatGetLocalSize(A, &m, &n));
1511:   PetscCall(ISGetIndices(rowp, &rwant));
1512:   PetscCall(ISGetIndices(colp, &cwant));
1513:   PetscCall(PetscMalloc3(PetscMax(m, n), &work, m, &rdest, n, &cdest));

1515:   /* Invert row permutation to find out where my rows should go */
1516:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &rowsf));
1517:   PetscCall(PetscSFSetGraphLayout(rowsf, A->rmap, A->rmap->n, NULL, PETSC_OWN_POINTER, rwant));
1518:   PetscCall(PetscSFSetFromOptions(rowsf));
1519:   for (i = 0; i < m; i++) work[i] = A->rmap->rstart + i;
1520:   PetscCall(PetscSFReduceBegin(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));
1521:   PetscCall(PetscSFReduceEnd(rowsf, MPIU_INT, work, rdest, MPI_REPLACE));

1523:   /* Invert column permutation to find out where my columns should go */
1524:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1525:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, A->cmap->n, NULL, PETSC_OWN_POINTER, cwant));
1526:   PetscCall(PetscSFSetFromOptions(sf));
1527:   for (i = 0; i < n; i++) work[i] = A->cmap->rstart + i;
1528:   PetscCall(PetscSFReduceBegin(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1529:   PetscCall(PetscSFReduceEnd(sf, MPIU_INT, work, cdest, MPI_REPLACE));
1530:   PetscCall(PetscSFDestroy(&sf));

1532:   PetscCall(ISRestoreIndices(rowp, &rwant));
1533:   PetscCall(ISRestoreIndices(colp, &cwant));
1534:   PetscCall(MatMPIAIJGetSeqAIJ(A, &aA, &aB, &gcols));

1536:   /* Find out where my gcols should go */
1537:   PetscCall(MatGetSize(aB, NULL, &ng));
1538:   PetscCall(PetscMalloc1(ng, &gcdest));
1539:   PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1540:   PetscCall(PetscSFSetGraphLayout(sf, A->cmap, ng, NULL, PETSC_OWN_POINTER, gcols));
1541:   PetscCall(PetscSFSetFromOptions(sf));
1542:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1543:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, cdest, gcdest, MPI_REPLACE));
1544:   PetscCall(PetscSFDestroy(&sf));

1546:   PetscCall(PetscCalloc4(m, &dnnz, m, &onnz, m, &tdnnz, m, &tonnz));
1547:   PetscCall(MatGetRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1548:   PetscCall(MatGetRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1549:   for (i = 0; i < m; i++) {
1550:     PetscInt    row = rdest[i];
1551:     PetscMPIInt rowner;
1552:     PetscCall(PetscLayoutFindOwner(A->rmap, row, &rowner));
1553:     for (j = ai[i]; j < ai[i + 1]; j++) {
1554:       PetscInt    col = cdest[aj[j]];
1555:       PetscMPIInt cowner;
1556:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner)); /* Could build an index for the columns to eliminate this search */
1557:       if (rowner == cowner) dnnz[i]++;
1558:       else onnz[i]++;
1559:     }
1560:     for (j = bi[i]; j < bi[i + 1]; j++) {
1561:       PetscInt    col = gcdest[bj[j]];
1562:       PetscMPIInt cowner;
1563:       PetscCall(PetscLayoutFindOwner(A->cmap, col, &cowner));
1564:       if (rowner == cowner) dnnz[i]++;
1565:       else onnz[i]++;
1566:     }
1567:   }
1568:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1569:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, dnnz, tdnnz, MPI_REPLACE));
1570:   PetscCall(PetscSFBcastBegin(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1571:   PetscCall(PetscSFBcastEnd(rowsf, MPIU_INT, onnz, tonnz, MPI_REPLACE));
1572:   PetscCall(PetscSFDestroy(&rowsf));

1574:   PetscCall(MatCreateAIJ(PetscObjectComm((PetscObject)A), A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N, 0, tdnnz, 0, tonnz, &Aperm));
1575:   PetscCall(MatSeqAIJGetArray(aA, &aa));
1576:   PetscCall(MatSeqAIJGetArray(aB, &ba));
1577:   for (i = 0; i < m; i++) {
1578:     PetscInt *acols = dnnz, *bcols = onnz; /* Repurpose now-unneeded arrays */
1579:     PetscInt  j0, rowlen;
1580:     rowlen = ai[i + 1] - ai[i];
1581:     for (j0 = j = 0; j < rowlen; j0 = j) { /* rowlen could be larger than number of rows m, so sum in batches */
1582:       for (; j < PetscMin(rowlen, j0 + m); j++) acols[j - j0] = cdest[aj[ai[i] + j]];
1583:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, acols, aa + ai[i] + j0, INSERT_VALUES));
1584:     }
1585:     rowlen = bi[i + 1] - bi[i];
1586:     for (j0 = j = 0; j < rowlen; j0 = j) {
1587:       for (; j < PetscMin(rowlen, j0 + m); j++) bcols[j - j0] = gcdest[bj[bi[i] + j]];
1588:       PetscCall(MatSetValues(Aperm, 1, &rdest[i], j - j0, bcols, ba + bi[i] + j0, INSERT_VALUES));
1589:     }
1590:   }
1591:   PetscCall(MatAssemblyBegin(Aperm, MAT_FINAL_ASSEMBLY));
1592:   PetscCall(MatAssemblyEnd(Aperm, MAT_FINAL_ASSEMBLY));
1593:   PetscCall(MatRestoreRowIJ(aA, 0, PETSC_FALSE, PETSC_FALSE, &anz, &ai, &aj, &done));
1594:   PetscCall(MatRestoreRowIJ(aB, 0, PETSC_FALSE, PETSC_FALSE, &bnz, &bi, &bj, &done));
1595:   PetscCall(MatSeqAIJRestoreArray(aA, &aa));
1596:   PetscCall(MatSeqAIJRestoreArray(aB, &ba));
1597:   PetscCall(PetscFree4(dnnz, onnz, tdnnz, tonnz));
1598:   PetscCall(PetscFree3(work, rdest, cdest));
1599:   PetscCall(PetscFree(gcdest));
1600:   if (parcolp) PetscCall(ISDestroy(&colp));
1601:   *B = Aperm;
1602:   PetscFunctionReturn(PETSC_SUCCESS);
1603: }

1605: static PetscErrorCode MatGetGhosts_MPIAIJ(Mat mat, PetscInt *nghosts, const PetscInt *ghosts[])
1606: {
1607:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1609:   PetscFunctionBegin;
1610:   PetscCall(MatGetSize(aij->B, NULL, nghosts));
1611:   if (ghosts) *ghosts = aij->garray;
1612:   PetscFunctionReturn(PETSC_SUCCESS);
1613: }

1615: static PetscErrorCode MatGetInfo_MPIAIJ(Mat matin, MatInfoType flag, MatInfo *info)
1616: {
1617:   Mat_MPIAIJ    *mat = (Mat_MPIAIJ *)matin->data;
1618:   Mat            A = mat->A, B = mat->B;
1619:   PetscLogDouble isend[5], irecv[5];

1621:   PetscFunctionBegin;
1622:   info->block_size = 1.0;
1623:   PetscCall(MatGetInfo(A, MAT_LOCAL, info));

1625:   isend[0] = info->nz_used;
1626:   isend[1] = info->nz_allocated;
1627:   isend[2] = info->nz_unneeded;
1628:   isend[3] = info->memory;
1629:   isend[4] = info->mallocs;

1631:   PetscCall(MatGetInfo(B, MAT_LOCAL, info));

1633:   isend[0] += info->nz_used;
1634:   isend[1] += info->nz_allocated;
1635:   isend[2] += info->nz_unneeded;
1636:   isend[3] += info->memory;
1637:   isend[4] += info->mallocs;
1638:   if (flag == MAT_LOCAL) {
1639:     info->nz_used      = isend[0];
1640:     info->nz_allocated = isend[1];
1641:     info->nz_unneeded  = isend[2];
1642:     info->memory       = isend[3];
1643:     info->mallocs      = isend[4];
1644:   } else if (flag == MAT_GLOBAL_MAX) {
1645:     PetscCallMPI(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_MAX, PetscObjectComm((PetscObject)matin)));

1647:     info->nz_used      = irecv[0];
1648:     info->nz_allocated = irecv[1];
1649:     info->nz_unneeded  = irecv[2];
1650:     info->memory       = irecv[3];
1651:     info->mallocs      = irecv[4];
1652:   } else if (flag == MAT_GLOBAL_SUM) {
1653:     PetscCallMPI(MPIU_Allreduce(isend, irecv, 5, MPIU_PETSCLOGDOUBLE, MPI_SUM, PetscObjectComm((PetscObject)matin)));

1655:     info->nz_used      = irecv[0];
1656:     info->nz_allocated = irecv[1];
1657:     info->nz_unneeded  = irecv[2];
1658:     info->memory       = irecv[3];
1659:     info->mallocs      = irecv[4];
1660:   }
1661:   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1662:   info->fill_ratio_needed = 0;
1663:   info->factor_mallocs    = 0;
1664:   PetscFunctionReturn(PETSC_SUCCESS);
1665: }

1667: PetscErrorCode MatSetOption_MPIAIJ(Mat A, MatOption op, PetscBool flg)
1668: {
1669:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

1671:   PetscFunctionBegin;
1672:   switch (op) {
1673:   case MAT_NEW_NONZERO_LOCATIONS:
1674:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1675:   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1676:   case MAT_KEEP_NONZERO_PATTERN:
1677:   case MAT_NEW_NONZERO_LOCATION_ERR:
1678:   case MAT_USE_INODES:
1679:   case MAT_IGNORE_ZERO_ENTRIES:
1680:   case MAT_FORM_EXPLICIT_TRANSPOSE:
1681:     MatCheckPreallocated(A, 1);
1682:     PetscCall(MatSetOption(a->A, op, flg));
1683:     PetscCall(MatSetOption(a->B, op, flg));
1684:     break;
1685:   case MAT_ROW_ORIENTED:
1686:     MatCheckPreallocated(A, 1);
1687:     a->roworiented = flg;

1689:     PetscCall(MatSetOption(a->A, op, flg));
1690:     PetscCall(MatSetOption(a->B, op, flg));
1691:     break;
1692:   case MAT_FORCE_DIAGONAL_ENTRIES:
1693:   case MAT_SORTED_FULL:
1694:     PetscCall(PetscInfo(A, "Option %s ignored\n", MatOptions[op]));
1695:     break;
1696:   case MAT_IGNORE_OFF_PROC_ENTRIES:
1697:     a->donotstash = flg;
1698:     break;
1699:   /* Symmetry flags are handled directly by MatSetOption() and they don't affect preallocation */
1700:   case MAT_SPD:
1701:   case MAT_SYMMETRIC:
1702:   case MAT_STRUCTURALLY_SYMMETRIC:
1703:   case MAT_HERMITIAN:
1704:   case MAT_SYMMETRY_ETERNAL:
1705:   case MAT_STRUCTURAL_SYMMETRY_ETERNAL:
1706:   case MAT_SPD_ETERNAL:
1707:     /* if the diagonal matrix is square it inherits some of the properties above */
1708:     break;
1709:   case MAT_SUBMAT_SINGLEIS:
1710:     A->submat_singleis = flg;
1711:     break;
1712:   case MAT_STRUCTURE_ONLY:
1713:     /* The option is handled directly by MatSetOption() */
1714:     break;
1715:   default:
1716:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "unknown option %d", op);
1717:   }
1718:   PetscFunctionReturn(PETSC_SUCCESS);
1719: }

1721: PetscErrorCode MatGetRow_MPIAIJ(Mat matin, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1722: {
1723:   Mat_MPIAIJ  *mat = (Mat_MPIAIJ *)matin->data;
1724:   PetscScalar *vworkA, *vworkB, **pvA, **pvB, *v_p;
1725:   PetscInt     i, *cworkA, *cworkB, **pcA, **pcB, cstart = matin->cmap->rstart;
1726:   PetscInt     nztot, nzA, nzB, lrow, rstart = matin->rmap->rstart, rend = matin->rmap->rend;
1727:   PetscInt    *cmap, *idx_p;

1729:   PetscFunctionBegin;
1730:   PetscCheck(!mat->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Already active");
1731:   mat->getrowactive = PETSC_TRUE;

1733:   if (!mat->rowvalues && (idx || v)) {
1734:     /*
1735:         allocate enough space to hold information from the longest row.
1736:     */
1737:     Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)mat->A->data, *Ba = (Mat_SeqAIJ *)mat->B->data;
1738:     PetscInt    max = 1, tmp;
1739:     for (i = 0; i < matin->rmap->n; i++) {
1740:       tmp = Aa->i[i + 1] - Aa->i[i] + Ba->i[i + 1] - Ba->i[i];
1741:       if (max < tmp) max = tmp;
1742:     }
1743:     PetscCall(PetscMalloc2(max, &mat->rowvalues, max, &mat->rowindices));
1744:   }

1746:   PetscCheck(row >= rstart && row < rend, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Only local rows");
1747:   lrow = row - rstart;

1749:   pvA = &vworkA;
1750:   pcA = &cworkA;
1751:   pvB = &vworkB;
1752:   pcB = &cworkB;
1753:   if (!v) {
1754:     pvA = NULL;
1755:     pvB = NULL;
1756:   }
1757:   if (!idx) {
1758:     pcA = NULL;
1759:     if (!v) pcB = NULL;
1760:   }
1761:   PetscCall((*mat->A->ops->getrow)(mat->A, lrow, &nzA, pcA, pvA));
1762:   PetscCall((*mat->B->ops->getrow)(mat->B, lrow, &nzB, pcB, pvB));
1763:   nztot = nzA + nzB;

1765:   cmap = mat->garray;
1766:   if (v || idx) {
1767:     if (nztot) {
1768:       /* Sort by increasing column numbers, assuming A and B already sorted */
1769:       PetscInt imark = -1;
1770:       if (v) {
1771:         *v = v_p = mat->rowvalues;
1772:         for (i = 0; i < nzB; i++) {
1773:           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1774:           else break;
1775:         }
1776:         imark = i;
1777:         for (i = 0; i < nzA; i++) v_p[imark + i] = vworkA[i];
1778:         for (i = imark; i < nzB; i++) v_p[nzA + i] = vworkB[i];
1779:       }
1780:       if (idx) {
1781:         *idx = idx_p = mat->rowindices;
1782:         if (imark > -1) {
1783:           for (i = 0; i < imark; i++) idx_p[i] = cmap[cworkB[i]];
1784:         } else {
1785:           for (i = 0; i < nzB; i++) {
1786:             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1787:             else break;
1788:           }
1789:           imark = i;
1790:         }
1791:         for (i = 0; i < nzA; i++) idx_p[imark + i] = cstart + cworkA[i];
1792:         for (i = imark; i < nzB; i++) idx_p[nzA + i] = cmap[cworkB[i]];
1793:       }
1794:     } else {
1795:       if (idx) *idx = NULL;
1796:       if (v) *v = NULL;
1797:     }
1798:   }
1799:   *nz = nztot;
1800:   PetscCall((*mat->A->ops->restorerow)(mat->A, lrow, &nzA, pcA, pvA));
1801:   PetscCall((*mat->B->ops->restorerow)(mat->B, lrow, &nzB, pcB, pvB));
1802:   PetscFunctionReturn(PETSC_SUCCESS);
1803: }

1805: PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat, PetscInt row, PetscInt *nz, PetscInt **idx, PetscScalar **v)
1806: {
1807:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

1809:   PetscFunctionBegin;
1810:   PetscCheck(aij->getrowactive, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "MatGetRow() must be called first");
1811:   aij->getrowactive = PETSC_FALSE;
1812:   PetscFunctionReturn(PETSC_SUCCESS);
1813: }

1815: static PetscErrorCode MatNorm_MPIAIJ(Mat mat, NormType type, PetscReal *norm)
1816: {
1817:   Mat_MPIAIJ      *aij  = (Mat_MPIAIJ *)mat->data;
1818:   Mat_SeqAIJ      *amat = (Mat_SeqAIJ *)aij->A->data, *bmat = (Mat_SeqAIJ *)aij->B->data;
1819:   PetscInt         i, j, cstart = mat->cmap->rstart;
1820:   PetscReal        sum = 0.0;
1821:   const MatScalar *v, *amata, *bmata;
1822:   PetscMPIInt      iN;

1824:   PetscFunctionBegin;
1825:   if (aij->size == 1) {
1826:     PetscCall(MatNorm(aij->A, type, norm));
1827:   } else {
1828:     PetscCall(MatSeqAIJGetArrayRead(aij->A, &amata));
1829:     PetscCall(MatSeqAIJGetArrayRead(aij->B, &bmata));
1830:     if (type == NORM_FROBENIUS) {
1831:       v = amata;
1832:       for (i = 0; i < amat->nz; i++) {
1833:         sum += PetscRealPart(PetscConj(*v) * (*v));
1834:         v++;
1835:       }
1836:       v = bmata;
1837:       for (i = 0; i < bmat->nz; i++) {
1838:         sum += PetscRealPart(PetscConj(*v) * (*v));
1839:         v++;
1840:       }
1841:       PetscCallMPI(MPIU_Allreduce(&sum, norm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1842:       *norm = PetscSqrtReal(*norm);
1843:       PetscCall(PetscLogFlops(2.0 * amat->nz + 2.0 * bmat->nz));
1844:     } else if (type == NORM_1) { /* max column norm */
1845:       PetscReal *tmp, *tmp2;
1846:       PetscInt  *jj, *garray = aij->garray;
1847:       PetscCall(PetscCalloc1(mat->cmap->N + 1, &tmp));
1848:       PetscCall(PetscMalloc1(mat->cmap->N + 1, &tmp2));
1849:       *norm = 0.0;
1850:       v     = amata;
1851:       jj    = amat->j;
1852:       for (j = 0; j < amat->nz; j++) {
1853:         tmp[cstart + *jj++] += PetscAbsScalar(*v);
1854:         v++;
1855:       }
1856:       v  = bmata;
1857:       jj = bmat->j;
1858:       for (j = 0; j < bmat->nz; j++) {
1859:         tmp[garray[*jj++]] += PetscAbsScalar(*v);
1860:         v++;
1861:       }
1862:       PetscCall(PetscMPIIntCast(mat->cmap->N, &iN));
1863:       PetscCallMPI(MPIU_Allreduce(tmp, tmp2, iN, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)mat)));
1864:       for (j = 0; j < mat->cmap->N; j++) {
1865:         if (tmp2[j] > *norm) *norm = tmp2[j];
1866:       }
1867:       PetscCall(PetscFree(tmp));
1868:       PetscCall(PetscFree(tmp2));
1869:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1870:     } else if (type == NORM_INFINITY) { /* max row norm */
1871:       PetscReal ntemp = 0.0;
1872:       for (j = 0; j < aij->A->rmap->n; j++) {
1873:         v   = PetscSafePointerPlusOffset(amata, amat->i[j]);
1874:         sum = 0.0;
1875:         for (i = 0; i < amat->i[j + 1] - amat->i[j]; i++) {
1876:           sum += PetscAbsScalar(*v);
1877:           v++;
1878:         }
1879:         v = PetscSafePointerPlusOffset(bmata, bmat->i[j]);
1880:         for (i = 0; i < bmat->i[j + 1] - bmat->i[j]; i++) {
1881:           sum += PetscAbsScalar(*v);
1882:           v++;
1883:         }
1884:         if (sum > ntemp) ntemp = sum;
1885:       }
1886:       PetscCallMPI(MPIU_Allreduce(&ntemp, norm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)mat)));
1887:       PetscCall(PetscLogFlops(PetscMax(amat->nz + bmat->nz - 1, 0)));
1888:     } else SETERRQ(PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "No support for two norm");
1889:     PetscCall(MatSeqAIJRestoreArrayRead(aij->A, &amata));
1890:     PetscCall(MatSeqAIJRestoreArrayRead(aij->B, &bmata));
1891:   }
1892:   PetscFunctionReturn(PETSC_SUCCESS);
1893: }

1895: static PetscErrorCode MatTranspose_MPIAIJ(Mat A, MatReuse reuse, Mat *matout)
1896: {
1897:   Mat_MPIAIJ      *a    = (Mat_MPIAIJ *)A->data, *b;
1898:   Mat_SeqAIJ      *Aloc = (Mat_SeqAIJ *)a->A->data, *Bloc = (Mat_SeqAIJ *)a->B->data, *sub_B_diag;
1899:   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;
1900:   const PetscInt  *ai, *aj, *bi, *bj, *B_diag_i;
1901:   Mat              B, A_diag, *B_diag;
1902:   const MatScalar *pbv, *bv;

1904:   PetscFunctionBegin;
1905:   if (reuse == MAT_REUSE_MATRIX) PetscCall(MatTransposeCheckNonzeroState_Private(A, *matout));
1906:   ma = A->rmap->n;
1907:   na = A->cmap->n;
1908:   mb = a->B->rmap->n;
1909:   nb = a->B->cmap->n;
1910:   ai = Aloc->i;
1911:   aj = Aloc->j;
1912:   bi = Bloc->i;
1913:   bj = Bloc->j;
1914:   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1915:     PetscInt            *d_nnz, *g_nnz, *o_nnz;
1916:     PetscSFNode         *oloc;
1917:     PETSC_UNUSED PetscSF sf;

1919:     PetscCall(PetscMalloc4(na, &d_nnz, na, &o_nnz, nb, &g_nnz, nb, &oloc));
1920:     /* compute d_nnz for preallocation */
1921:     PetscCall(PetscArrayzero(d_nnz, na));
1922:     for (i = 0; i < ai[ma]; i++) d_nnz[aj[i]]++;
1923:     /* compute local off-diagonal contributions */
1924:     PetscCall(PetscArrayzero(g_nnz, nb));
1925:     for (i = 0; i < bi[ma]; i++) g_nnz[bj[i]]++;
1926:     /* map those to global */
1927:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)A), &sf));
1928:     PetscCall(PetscSFSetGraphLayout(sf, A->cmap, nb, NULL, PETSC_USE_POINTER, a->garray));
1929:     PetscCall(PetscSFSetFromOptions(sf));
1930:     PetscCall(PetscArrayzero(o_nnz, na));
1931:     PetscCall(PetscSFReduceBegin(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1932:     PetscCall(PetscSFReduceEnd(sf, MPIU_INT, g_nnz, o_nnz, MPI_SUM));
1933:     PetscCall(PetscSFDestroy(&sf));

1935:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
1936:     PetscCall(MatSetSizes(B, A->cmap->n, A->rmap->n, N, M));
1937:     PetscCall(MatSetBlockSizes(B, PetscAbs(A->cmap->bs), PetscAbs(A->rmap->bs)));
1938:     PetscCall(MatSetType(B, ((PetscObject)A)->type_name));
1939:     PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
1940:     PetscCall(PetscFree4(d_nnz, o_nnz, g_nnz, oloc));
1941:   } else {
1942:     B = *matout;
1943:     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE));
1944:   }

1946:   b           = (Mat_MPIAIJ *)B->data;
1947:   A_diag      = a->A;
1948:   B_diag      = &b->A;
1949:   sub_B_diag  = (Mat_SeqAIJ *)(*B_diag)->data;
1950:   A_diag_ncol = A_diag->cmap->N;
1951:   B_diag_ilen = sub_B_diag->ilen;
1952:   B_diag_i    = sub_B_diag->i;

1954:   /* Set ilen for diagonal of B */
1955:   for (i = 0; i < A_diag_ncol; i++) B_diag_ilen[i] = B_diag_i[i + 1] - B_diag_i[i];

1957:   /* Transpose the diagonal part of the matrix. In contrast to the off-diagonal part, this can be done
1958:   very quickly (=without using MatSetValues), because all writes are local. */
1959:   PetscCall(MatTransposeSetPrecursor(A_diag, *B_diag));
1960:   PetscCall(MatTranspose(A_diag, MAT_REUSE_MATRIX, B_diag));

1962:   /* copy over the B part */
1963:   PetscCall(PetscMalloc1(bi[mb], &cols));
1964:   PetscCall(MatSeqAIJGetArrayRead(a->B, &bv));
1965:   pbv = bv;
1966:   row = A->rmap->rstart;
1967:   for (i = 0; i < bi[mb]; i++) cols[i] = a->garray[bj[i]];
1968:   cols_tmp = cols;
1969:   for (i = 0; i < mb; i++) {
1970:     ncol = bi[i + 1] - bi[i];
1971:     PetscCall(MatSetValues(B, ncol, cols_tmp, 1, &row, pbv, INSERT_VALUES));
1972:     row++;
1973:     if (pbv) pbv += ncol;
1974:     if (cols_tmp) cols_tmp += ncol;
1975:   }
1976:   PetscCall(PetscFree(cols));
1977:   PetscCall(MatSeqAIJRestoreArrayRead(a->B, &bv));

1979:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
1980:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
1981:   if (reuse == MAT_INITIAL_MATRIX || reuse == MAT_REUSE_MATRIX) {
1982:     *matout = B;
1983:   } else {
1984:     PetscCall(MatHeaderMerge(A, &B));
1985:   }
1986:   PetscFunctionReturn(PETSC_SUCCESS);
1987: }

1989: static PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat, Vec ll, Vec rr)
1990: {
1991:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;
1992:   Mat         a = aij->A, b = aij->B;
1993:   PetscInt    s1, s2, s3;

1995:   PetscFunctionBegin;
1996:   PetscCall(MatGetLocalSize(mat, &s2, &s3));
1997:   if (rr) {
1998:     PetscCall(VecGetLocalSize(rr, &s1));
1999:     PetscCheck(s1 == s3, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "right vector non-conforming local size");
2000:     /* Overlap communication with computation. */
2001:     PetscCall(VecScatterBegin(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
2002:   }
2003:   if (ll) {
2004:     PetscCall(VecGetLocalSize(ll, &s1));
2005:     PetscCheck(s1 == s2, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "left vector non-conforming local size");
2006:     PetscUseTypeMethod(b, diagonalscale, ll, NULL);
2007:   }
2008:   /* scale  the diagonal block */
2009:   PetscUseTypeMethod(a, diagonalscale, ll, rr);

2011:   if (rr) {
2012:     /* Do a scatter end and then right scale the off-diagonal block */
2013:     PetscCall(VecScatterEnd(aij->Mvctx, rr, aij->lvec, INSERT_VALUES, SCATTER_FORWARD));
2014:     PetscUseTypeMethod(b, diagonalscale, NULL, aij->lvec);
2015:   }
2016:   PetscFunctionReturn(PETSC_SUCCESS);
2017: }

2019: static PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2020: {
2021:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2023:   PetscFunctionBegin;
2024:   PetscCall(MatSetUnfactored(a->A));
2025:   PetscFunctionReturn(PETSC_SUCCESS);
2026: }

2028: static PetscErrorCode MatEqual_MPIAIJ(Mat A, Mat B, PetscBool *flag)
2029: {
2030:   Mat_MPIAIJ *matB = (Mat_MPIAIJ *)B->data, *matA = (Mat_MPIAIJ *)A->data;
2031:   Mat         a, b, c, d;
2032:   PetscBool   flg;

2034:   PetscFunctionBegin;
2035:   a = matA->A;
2036:   b = matA->B;
2037:   c = matB->A;
2038:   d = matB->B;

2040:   PetscCall(MatEqual(a, c, &flg));
2041:   if (flg) PetscCall(MatEqual(b, d, &flg));
2042:   PetscCallMPI(MPIU_Allreduce(&flg, flag, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)A)));
2043:   PetscFunctionReturn(PETSC_SUCCESS);
2044: }

2046: static PetscErrorCode MatCopy_MPIAIJ(Mat A, Mat B, MatStructure str)
2047: {
2048:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2049:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2051:   PetscFunctionBegin;
2052:   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2053:   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2054:     /* because of the column compression in the off-processor part of the matrix a->B,
2055:        the number of columns in a->B and b->B may be different, hence we cannot call
2056:        the MatCopy() directly on the two parts. If need be, we can provide a more
2057:        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2058:        then copying the submatrices */
2059:     PetscCall(MatCopy_Basic(A, B, str));
2060:   } else {
2061:     PetscCall(MatCopy(a->A, b->A, str));
2062:     PetscCall(MatCopy(a->B, b->B, str));
2063:   }
2064:   PetscCall(PetscObjectStateIncrease((PetscObject)B));
2065:   PetscFunctionReturn(PETSC_SUCCESS);
2066: }

2068: /*
2069:    Computes the number of nonzeros per row needed for preallocation when X and Y
2070:    have different nonzero structure.
2071: */
2072: 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)
2073: {
2074:   PetscInt i, j, k, nzx, nzy;

2076:   PetscFunctionBegin;
2077:   /* Set the number of nonzeros in the new matrix */
2078:   for (i = 0; i < m; i++) {
2079:     const PetscInt *xjj = PetscSafePointerPlusOffset(xj, xi[i]), *yjj = PetscSafePointerPlusOffset(yj, yi[i]);
2080:     nzx    = xi[i + 1] - xi[i];
2081:     nzy    = yi[i + 1] - yi[i];
2082:     nnz[i] = 0;
2083:     for (j = 0, k = 0; j < nzx; j++) {                                /* Point in X */
2084:       for (; k < nzy && yltog[yjj[k]] < xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2085:       if (k < nzy && yltog[yjj[k]] == xltog[xjj[j]]) k++;             /* Skip duplicate */
2086:       nnz[i]++;
2087:     }
2088:     for (; k < nzy; k++) nnz[i]++;
2089:   }
2090:   PetscFunctionReturn(PETSC_SUCCESS);
2091: }

2093: /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2094: static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y, const PetscInt *yltog, Mat X, const PetscInt *xltog, PetscInt *nnz)
2095: {
2096:   PetscInt    m = Y->rmap->N;
2097:   Mat_SeqAIJ *x = (Mat_SeqAIJ *)X->data;
2098:   Mat_SeqAIJ *y = (Mat_SeqAIJ *)Y->data;

2100:   PetscFunctionBegin;
2101:   PetscCall(MatAXPYGetPreallocation_MPIX_private(m, x->i, x->j, xltog, y->i, y->j, yltog, nnz));
2102:   PetscFunctionReturn(PETSC_SUCCESS);
2103: }

2105: static PetscErrorCode MatAXPY_MPIAIJ(Mat Y, PetscScalar a, Mat X, MatStructure str)
2106: {
2107:   Mat_MPIAIJ *xx = (Mat_MPIAIJ *)X->data, *yy = (Mat_MPIAIJ *)Y->data;

2109:   PetscFunctionBegin;
2110:   if (str == SAME_NONZERO_PATTERN) {
2111:     PetscCall(MatAXPY(yy->A, a, xx->A, str));
2112:     PetscCall(MatAXPY(yy->B, a, xx->B, str));
2113:   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2114:     PetscCall(MatAXPY_Basic(Y, a, X, str));
2115:   } else {
2116:     Mat       B;
2117:     PetscInt *nnz_d, *nnz_o;

2119:     PetscCall(PetscMalloc1(yy->A->rmap->N, &nnz_d));
2120:     PetscCall(PetscMalloc1(yy->B->rmap->N, &nnz_o));
2121:     PetscCall(MatCreate(PetscObjectComm((PetscObject)Y), &B));
2122:     PetscCall(PetscObjectSetName((PetscObject)B, ((PetscObject)Y)->name));
2123:     PetscCall(MatSetLayouts(B, Y->rmap, Y->cmap));
2124:     PetscCall(MatSetType(B, ((PetscObject)Y)->type_name));
2125:     PetscCall(MatAXPYGetPreallocation_SeqAIJ(yy->A, xx->A, nnz_d));
2126:     PetscCall(MatAXPYGetPreallocation_MPIAIJ(yy->B, yy->garray, xx->B, xx->garray, nnz_o));
2127:     PetscCall(MatMPIAIJSetPreallocation(B, 0, nnz_d, 0, nnz_o));
2128:     PetscCall(MatAXPY_BasicWithPreallocation(B, Y, a, X, str));
2129:     PetscCall(MatHeaderMerge(Y, &B));
2130:     PetscCall(PetscFree(nnz_d));
2131:     PetscCall(PetscFree(nnz_o));
2132:   }
2133:   PetscFunctionReturn(PETSC_SUCCESS);
2134: }

2136: PETSC_INTERN PetscErrorCode MatConjugate_SeqAIJ(Mat);

2138: static PetscErrorCode MatConjugate_MPIAIJ(Mat mat)
2139: {
2140:   PetscFunctionBegin;
2141:   if (PetscDefined(USE_COMPLEX)) {
2142:     Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2144:     PetscCall(MatConjugate_SeqAIJ(aij->A));
2145:     PetscCall(MatConjugate_SeqAIJ(aij->B));
2146:   }
2147:   PetscFunctionReturn(PETSC_SUCCESS);
2148: }

2150: static PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2151: {
2152:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2154:   PetscFunctionBegin;
2155:   PetscCall(MatRealPart(a->A));
2156:   PetscCall(MatRealPart(a->B));
2157:   PetscFunctionReturn(PETSC_SUCCESS);
2158: }

2160: static PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2161: {
2162:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2164:   PetscFunctionBegin;
2165:   PetscCall(MatImaginaryPart(a->A));
2166:   PetscCall(MatImaginaryPart(a->B));
2167:   PetscFunctionReturn(PETSC_SUCCESS);
2168: }

2170: static PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2171: {
2172:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
2173:   PetscInt           i, *idxb = NULL, m = A->rmap->n;
2174:   PetscScalar       *va, *vv;
2175:   Vec                vB, vA;
2176:   const PetscScalar *vb;

2178:   PetscFunctionBegin;
2179:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2180:   PetscCall(MatGetRowMaxAbs(a->A, vA, idx));

2182:   PetscCall(VecGetArrayWrite(vA, &va));
2183:   if (idx) {
2184:     for (i = 0; i < m; i++) {
2185:       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2186:     }
2187:   }

2189:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2190:   PetscCall(PetscMalloc1(m, &idxb));
2191:   PetscCall(MatGetRowMaxAbs(a->B, vB, idxb));

2193:   PetscCall(VecGetArrayWrite(v, &vv));
2194:   PetscCall(VecGetArrayRead(vB, &vb));
2195:   for (i = 0; i < m; i++) {
2196:     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2197:       vv[i] = vb[i];
2198:       if (idx) idx[i] = a->garray[idxb[i]];
2199:     } else {
2200:       vv[i] = va[i];
2201:       if (idx && PetscAbsScalar(va[i]) == PetscAbsScalar(vb[i]) && idxb[i] != -1 && idx[i] > a->garray[idxb[i]]) idx[i] = a->garray[idxb[i]];
2202:     }
2203:   }
2204:   PetscCall(VecRestoreArrayWrite(vA, &vv));
2205:   PetscCall(VecRestoreArrayWrite(vA, &va));
2206:   PetscCall(VecRestoreArrayRead(vB, &vb));
2207:   PetscCall(PetscFree(idxb));
2208:   PetscCall(VecDestroy(&vA));
2209:   PetscCall(VecDestroy(&vB));
2210:   PetscFunctionReturn(PETSC_SUCCESS);
2211: }

2213: static PetscErrorCode MatGetRowSumAbs_MPIAIJ(Mat A, Vec v)
2214: {
2215:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
2216:   Vec         vB, vA;

2218:   PetscFunctionBegin;
2219:   PetscCall(MatCreateVecs(a->A, NULL, &vA));
2220:   PetscCall(MatGetRowSumAbs(a->A, vA));
2221:   PetscCall(MatCreateVecs(a->B, NULL, &vB));
2222:   PetscCall(MatGetRowSumAbs(a->B, vB));
2223:   PetscCall(VecAXPY(vA, 1.0, vB));
2224:   PetscCall(VecDestroy(&vB));
2225:   PetscCall(VecCopy(vA, v));
2226:   PetscCall(VecDestroy(&vA));
2227:   PetscFunctionReturn(PETSC_SUCCESS);
2228: }

2230: static PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2231: {
2232:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2233:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2234:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2235:   PetscInt          *cmap = mat->garray;
2236:   PetscInt          *diagIdx, *offdiagIdx;
2237:   Vec                diagV, offdiagV;
2238:   PetscScalar       *a, *diagA, *offdiagA;
2239:   const PetscScalar *ba, *bav;
2240:   PetscInt           r, j, col, ncols, *bi, *bj;
2241:   Mat                B = mat->B;
2242:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2244:   PetscFunctionBegin;
2245:   /* When a process holds entire A and other processes have no entry */
2246:   if (A->cmap->N == n) {
2247:     PetscCall(VecGetArrayWrite(v, &diagA));
2248:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2249:     PetscCall(MatGetRowMinAbs(mat->A, diagV, idx));
2250:     PetscCall(VecDestroy(&diagV));
2251:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2252:     PetscFunctionReturn(PETSC_SUCCESS);
2253:   } else if (n == 0) {
2254:     if (m) {
2255:       PetscCall(VecGetArrayWrite(v, &a));
2256:       for (r = 0; r < m; r++) {
2257:         a[r] = 0.0;
2258:         if (idx) idx[r] = -1;
2259:       }
2260:       PetscCall(VecRestoreArrayWrite(v, &a));
2261:     }
2262:     PetscFunctionReturn(PETSC_SUCCESS);
2263:   }

2265:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2266:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2267:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2268:   PetscCall(MatGetRowMinAbs(mat->A, diagV, diagIdx));

2270:   /* Get offdiagIdx[] for implicit 0.0 */
2271:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2272:   ba = bav;
2273:   bi = b->i;
2274:   bj = b->j;
2275:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2276:   for (r = 0; r < m; r++) {
2277:     ncols = bi[r + 1] - bi[r];
2278:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2279:       offdiagA[r]   = *ba;
2280:       offdiagIdx[r] = cmap[0];
2281:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2282:       offdiagA[r] = 0.0;

2284:       /* Find first hole in the cmap */
2285:       for (j = 0; j < ncols; j++) {
2286:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2287:         if (col > j && j < cstart) {
2288:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2289:           break;
2290:         } else if (col > j + n && j >= cstart) {
2291:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2292:           break;
2293:         }
2294:       }
2295:       if (j == ncols && ncols < A->cmap->N - n) {
2296:         /* a hole is outside compressed Bcols */
2297:         if (ncols == 0) {
2298:           if (cstart) {
2299:             offdiagIdx[r] = 0;
2300:           } else offdiagIdx[r] = cend;
2301:         } else { /* ncols > 0 */
2302:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2303:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2304:         }
2305:       }
2306:     }

2308:     for (j = 0; j < ncols; j++) {
2309:       if (PetscAbsScalar(offdiagA[r]) > PetscAbsScalar(*ba)) {
2310:         offdiagA[r]   = *ba;
2311:         offdiagIdx[r] = cmap[*bj];
2312:       }
2313:       ba++;
2314:       bj++;
2315:     }
2316:   }

2318:   PetscCall(VecGetArrayWrite(v, &a));
2319:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2320:   for (r = 0; r < m; ++r) {
2321:     if (PetscAbsScalar(diagA[r]) < PetscAbsScalar(offdiagA[r])) {
2322:       a[r] = diagA[r];
2323:       if (idx) idx[r] = cstart + diagIdx[r];
2324:     } else if (PetscAbsScalar(diagA[r]) == PetscAbsScalar(offdiagA[r])) {
2325:       a[r] = diagA[r];
2326:       if (idx) {
2327:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2328:           idx[r] = cstart + diagIdx[r];
2329:         } else idx[r] = offdiagIdx[r];
2330:       }
2331:     } else {
2332:       a[r] = offdiagA[r];
2333:       if (idx) idx[r] = offdiagIdx[r];
2334:     }
2335:   }
2336:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2337:   PetscCall(VecRestoreArrayWrite(v, &a));
2338:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2339:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2340:   PetscCall(VecDestroy(&diagV));
2341:   PetscCall(VecDestroy(&offdiagV));
2342:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2343:   PetscFunctionReturn(PETSC_SUCCESS);
2344: }

2346: static PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2347: {
2348:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2349:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2350:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2351:   PetscInt          *cmap = mat->garray;
2352:   PetscInt          *diagIdx, *offdiagIdx;
2353:   Vec                diagV, offdiagV;
2354:   PetscScalar       *a, *diagA, *offdiagA;
2355:   const PetscScalar *ba, *bav;
2356:   PetscInt           r, j, col, ncols, *bi, *bj;
2357:   Mat                B = mat->B;
2358:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2360:   PetscFunctionBegin;
2361:   /* When a process holds entire A and other processes have no entry */
2362:   if (A->cmap->N == n) {
2363:     PetscCall(VecGetArrayWrite(v, &diagA));
2364:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2365:     PetscCall(MatGetRowMin(mat->A, diagV, idx));
2366:     PetscCall(VecDestroy(&diagV));
2367:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2368:     PetscFunctionReturn(PETSC_SUCCESS);
2369:   } else if (n == 0) {
2370:     if (m) {
2371:       PetscCall(VecGetArrayWrite(v, &a));
2372:       for (r = 0; r < m; r++) {
2373:         a[r] = PETSC_MAX_REAL;
2374:         if (idx) idx[r] = -1;
2375:       }
2376:       PetscCall(VecRestoreArrayWrite(v, &a));
2377:     }
2378:     PetscFunctionReturn(PETSC_SUCCESS);
2379:   }

2381:   PetscCall(PetscCalloc2(m, &diagIdx, m, &offdiagIdx));
2382:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2383:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2384:   PetscCall(MatGetRowMin(mat->A, diagV, diagIdx));

2386:   /* Get offdiagIdx[] for implicit 0.0 */
2387:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2388:   ba = bav;
2389:   bi = b->i;
2390:   bj = b->j;
2391:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2392:   for (r = 0; r < m; r++) {
2393:     ncols = bi[r + 1] - bi[r];
2394:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2395:       offdiagA[r]   = *ba;
2396:       offdiagIdx[r] = cmap[0];
2397:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2398:       offdiagA[r] = 0.0;

2400:       /* Find first hole in the cmap */
2401:       for (j = 0; j < ncols; j++) {
2402:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2403:         if (col > j && j < cstart) {
2404:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2405:           break;
2406:         } else if (col > j + n && j >= cstart) {
2407:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2408:           break;
2409:         }
2410:       }
2411:       if (j == ncols && ncols < A->cmap->N - n) {
2412:         /* a hole is outside compressed Bcols */
2413:         if (ncols == 0) {
2414:           if (cstart) {
2415:             offdiagIdx[r] = 0;
2416:           } else offdiagIdx[r] = cend;
2417:         } else { /* ncols > 0 */
2418:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2419:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2420:         }
2421:       }
2422:     }

2424:     for (j = 0; j < ncols; j++) {
2425:       if (PetscRealPart(offdiagA[r]) > PetscRealPart(*ba)) {
2426:         offdiagA[r]   = *ba;
2427:         offdiagIdx[r] = cmap[*bj];
2428:       }
2429:       ba++;
2430:       bj++;
2431:     }
2432:   }

2434:   PetscCall(VecGetArrayWrite(v, &a));
2435:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2436:   for (r = 0; r < m; ++r) {
2437:     if (PetscRealPart(diagA[r]) < PetscRealPart(offdiagA[r])) {
2438:       a[r] = diagA[r];
2439:       if (idx) idx[r] = cstart + diagIdx[r];
2440:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2441:       a[r] = diagA[r];
2442:       if (idx) {
2443:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2444:           idx[r] = cstart + diagIdx[r];
2445:         } else idx[r] = offdiagIdx[r];
2446:       }
2447:     } else {
2448:       a[r] = offdiagA[r];
2449:       if (idx) idx[r] = offdiagIdx[r];
2450:     }
2451:   }
2452:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2453:   PetscCall(VecRestoreArrayWrite(v, &a));
2454:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2455:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2456:   PetscCall(VecDestroy(&diagV));
2457:   PetscCall(VecDestroy(&offdiagV));
2458:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2459:   PetscFunctionReturn(PETSC_SUCCESS);
2460: }

2462: static PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2463: {
2464:   Mat_MPIAIJ        *mat = (Mat_MPIAIJ *)A->data;
2465:   PetscInt           m = A->rmap->n, n = A->cmap->n;
2466:   PetscInt           cstart = A->cmap->rstart, cend = A->cmap->rend;
2467:   PetscInt          *cmap = mat->garray;
2468:   PetscInt          *diagIdx, *offdiagIdx;
2469:   Vec                diagV, offdiagV;
2470:   PetscScalar       *a, *diagA, *offdiagA;
2471:   const PetscScalar *ba, *bav;
2472:   PetscInt           r, j, col, ncols, *bi, *bj;
2473:   Mat                B = mat->B;
2474:   Mat_SeqAIJ        *b = (Mat_SeqAIJ *)B->data;

2476:   PetscFunctionBegin;
2477:   /* When a process holds entire A and other processes have no entry */
2478:   if (A->cmap->N == n) {
2479:     PetscCall(VecGetArrayWrite(v, &diagA));
2480:     PetscCall(VecCreateSeqWithArray(PETSC_COMM_SELF, 1, m, diagA, &diagV));
2481:     PetscCall(MatGetRowMax(mat->A, diagV, idx));
2482:     PetscCall(VecDestroy(&diagV));
2483:     PetscCall(VecRestoreArrayWrite(v, &diagA));
2484:     PetscFunctionReturn(PETSC_SUCCESS);
2485:   } else if (n == 0) {
2486:     if (m) {
2487:       PetscCall(VecGetArrayWrite(v, &a));
2488:       for (r = 0; r < m; r++) {
2489:         a[r] = PETSC_MIN_REAL;
2490:         if (idx) idx[r] = -1;
2491:       }
2492:       PetscCall(VecRestoreArrayWrite(v, &a));
2493:     }
2494:     PetscFunctionReturn(PETSC_SUCCESS);
2495:   }

2497:   PetscCall(PetscMalloc2(m, &diagIdx, m, &offdiagIdx));
2498:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &diagV));
2499:   PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &offdiagV));
2500:   PetscCall(MatGetRowMax(mat->A, diagV, diagIdx));

2502:   /* Get offdiagIdx[] for implicit 0.0 */
2503:   PetscCall(MatSeqAIJGetArrayRead(B, &bav));
2504:   ba = bav;
2505:   bi = b->i;
2506:   bj = b->j;
2507:   PetscCall(VecGetArrayWrite(offdiagV, &offdiagA));
2508:   for (r = 0; r < m; r++) {
2509:     ncols = bi[r + 1] - bi[r];
2510:     if (ncols == A->cmap->N - n) { /* Brow is dense */
2511:       offdiagA[r]   = *ba;
2512:       offdiagIdx[r] = cmap[0];
2513:     } else { /* Brow is sparse so already KNOW maximum is 0.0 or higher */
2514:       offdiagA[r] = 0.0;

2516:       /* Find first hole in the cmap */
2517:       for (j = 0; j < ncols; j++) {
2518:         col = cmap[bj[j]]; /* global column number = cmap[B column number] */
2519:         if (col > j && j < cstart) {
2520:           offdiagIdx[r] = j; /* global column number of first implicit 0.0 */
2521:           break;
2522:         } else if (col > j + n && j >= cstart) {
2523:           offdiagIdx[r] = j + n; /* global column number of first implicit 0.0 */
2524:           break;
2525:         }
2526:       }
2527:       if (j == ncols && ncols < A->cmap->N - n) {
2528:         /* a hole is outside compressed Bcols */
2529:         if (ncols == 0) {
2530:           if (cstart) {
2531:             offdiagIdx[r] = 0;
2532:           } else offdiagIdx[r] = cend;
2533:         } else { /* ncols > 0 */
2534:           offdiagIdx[r] = cmap[ncols - 1] + 1;
2535:           if (offdiagIdx[r] == cstart) offdiagIdx[r] += n;
2536:         }
2537:       }
2538:     }

2540:     for (j = 0; j < ncols; j++) {
2541:       if (PetscRealPart(offdiagA[r]) < PetscRealPart(*ba)) {
2542:         offdiagA[r]   = *ba;
2543:         offdiagIdx[r] = cmap[*bj];
2544:       }
2545:       ba++;
2546:       bj++;
2547:     }
2548:   }

2550:   PetscCall(VecGetArrayWrite(v, &a));
2551:   PetscCall(VecGetArrayRead(diagV, (const PetscScalar **)&diagA));
2552:   for (r = 0; r < m; ++r) {
2553:     if (PetscRealPart(diagA[r]) > PetscRealPart(offdiagA[r])) {
2554:       a[r] = diagA[r];
2555:       if (idx) idx[r] = cstart + diagIdx[r];
2556:     } else if (PetscRealPart(diagA[r]) == PetscRealPart(offdiagA[r])) {
2557:       a[r] = diagA[r];
2558:       if (idx) {
2559:         if (cstart + diagIdx[r] <= offdiagIdx[r]) {
2560:           idx[r] = cstart + diagIdx[r];
2561:         } else idx[r] = offdiagIdx[r];
2562:       }
2563:     } else {
2564:       a[r] = offdiagA[r];
2565:       if (idx) idx[r] = offdiagIdx[r];
2566:     }
2567:   }
2568:   PetscCall(MatSeqAIJRestoreArrayRead(B, &bav));
2569:   PetscCall(VecRestoreArrayWrite(v, &a));
2570:   PetscCall(VecRestoreArrayRead(diagV, (const PetscScalar **)&diagA));
2571:   PetscCall(VecRestoreArrayWrite(offdiagV, &offdiagA));
2572:   PetscCall(VecDestroy(&diagV));
2573:   PetscCall(VecDestroy(&offdiagV));
2574:   PetscCall(PetscFree2(diagIdx, offdiagIdx));
2575:   PetscFunctionReturn(PETSC_SUCCESS);
2576: }

2578: PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat, Mat *newmat)
2579: {
2580:   Mat *dummy;

2582:   PetscFunctionBegin;
2583:   PetscCall(MatCreateSubMatrix_MPIAIJ_All(mat, MAT_DO_NOT_GET_VALUES, MAT_INITIAL_MATRIX, &dummy));
2584:   *newmat = *dummy;
2585:   PetscCall(PetscFree(dummy));
2586:   PetscFunctionReturn(PETSC_SUCCESS);
2587: }

2589: static PetscErrorCode MatInvertBlockDiagonal_MPIAIJ(Mat A, const PetscScalar **values)
2590: {
2591:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2593:   PetscFunctionBegin;
2594:   PetscCall(MatInvertBlockDiagonal(a->A, values));
2595:   A->factorerrortype = a->A->factorerrortype;
2596:   PetscFunctionReturn(PETSC_SUCCESS);
2597: }

2599: static PetscErrorCode MatSetRandom_MPIAIJ(Mat x, PetscRandom rctx)
2600: {
2601:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)x->data;

2603:   PetscFunctionBegin;
2604:   PetscCheck(x->assembled || x->preallocated, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "MatSetRandom on an unassembled and unpreallocated MATMPIAIJ is not allowed");
2605:   PetscCall(MatSetRandom(aij->A, rctx));
2606:   if (x->assembled) {
2607:     PetscCall(MatSetRandom(aij->B, rctx));
2608:   } else {
2609:     PetscCall(MatSetRandomSkipColumnRange_SeqAIJ_Private(aij->B, x->cmap->rstart, x->cmap->rend, rctx));
2610:   }
2611:   PetscCall(MatAssemblyBegin(x, MAT_FINAL_ASSEMBLY));
2612:   PetscCall(MatAssemblyEnd(x, MAT_FINAL_ASSEMBLY));
2613:   PetscFunctionReturn(PETSC_SUCCESS);
2614: }

2616: static PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A, PetscBool sc)
2617: {
2618:   PetscFunctionBegin;
2619:   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2620:   else A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ;
2621:   PetscFunctionReturn(PETSC_SUCCESS);
2622: }

2624: /*@
2625:   MatMPIAIJGetNumberNonzeros - gets the number of nonzeros in the matrix on this MPI rank

2627:   Not Collective

2629:   Input Parameter:
2630: . A - the matrix

2632:   Output Parameter:
2633: . nz - the number of nonzeros

2635:   Level: advanced

2637: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2638: @*/
2639: PetscErrorCode MatMPIAIJGetNumberNonzeros(Mat A, PetscCount *nz)
2640: {
2641:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)A->data;
2642:   Mat_SeqAIJ *aaij = (Mat_SeqAIJ *)maij->A->data, *baij = (Mat_SeqAIJ *)maij->B->data;
2643:   PetscBool   isaij;

2645:   PetscFunctionBegin;
2646:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)A, MATMPIAIJ, &isaij));
2647:   PetscCheck(isaij, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Not for type %s", ((PetscObject)A)->type_name);
2648:   *nz = aaij->i[A->rmap->n] + baij->i[A->rmap->n];
2649:   PetscFunctionReturn(PETSC_SUCCESS);
2650: }

2652: /*@
2653:   MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap

2655:   Collective

2657:   Input Parameters:
2658: + A  - the matrix
2659: - sc - `PETSC_TRUE` indicates use the scalable algorithm (default is not to use the scalable algorithm)

2661:   Level: advanced

2663: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`
2664: @*/
2665: PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A, PetscBool sc)
2666: {
2667:   PetscFunctionBegin;
2668:   PetscTryMethod(A, "MatMPIAIJSetUseScalableIncreaseOverlap_C", (Mat, PetscBool), (A, sc));
2669:   PetscFunctionReturn(PETSC_SUCCESS);
2670: }

2672: PetscErrorCode MatSetFromOptions_MPIAIJ(Mat A, PetscOptionItems *PetscOptionsObject)
2673: {
2674:   PetscBool sc = PETSC_FALSE, flg;

2676:   PetscFunctionBegin;
2677:   PetscOptionsHeadBegin(PetscOptionsObject, "MPIAIJ options");
2678:   if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2679:   PetscCall(PetscOptionsBool("-mat_increase_overlap_scalable", "Use a scalable algorithm to compute the overlap", "MatIncreaseOverlap", sc, &sc, &flg));
2680:   if (flg) PetscCall(MatMPIAIJSetUseScalableIncreaseOverlap(A, sc));
2681:   PetscOptionsHeadEnd();
2682:   PetscFunctionReturn(PETSC_SUCCESS);
2683: }

2685: static PetscErrorCode MatShift_MPIAIJ(Mat Y, PetscScalar a)
2686: {
2687:   Mat_MPIAIJ *maij = (Mat_MPIAIJ *)Y->data;
2688:   Mat_SeqAIJ *aij  = (Mat_SeqAIJ *)maij->A->data;

2690:   PetscFunctionBegin;
2691:   if (!Y->preallocated) {
2692:     PetscCall(MatMPIAIJSetPreallocation(Y, 1, NULL, 0, NULL));
2693:   } else if (!aij->nz) { /* It does not matter if diagonals of Y only partially lie in maij->A. We just need an estimated preallocation. */
2694:     PetscInt nonew = aij->nonew;
2695:     PetscCall(MatSeqAIJSetPreallocation(maij->A, 1, NULL));
2696:     aij->nonew = nonew;
2697:   }
2698:   PetscCall(MatShift_Basic(Y, a));
2699:   PetscFunctionReturn(PETSC_SUCCESS);
2700: }

2702: static PetscErrorCode MatMissingDiagonal_MPIAIJ(Mat A, PetscBool *missing, PetscInt *d)
2703: {
2704:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2706:   PetscFunctionBegin;
2707:   PetscCheck(A->rmap->n == A->cmap->n, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only works for square matrices");
2708:   PetscCall(MatMissingDiagonal(a->A, missing, d));
2709:   if (d) {
2710:     PetscInt rstart;
2711:     PetscCall(MatGetOwnershipRange(A, &rstart, NULL));
2712:     *d += rstart;
2713:   }
2714:   PetscFunctionReturn(PETSC_SUCCESS);
2715: }

2717: static PetscErrorCode MatInvertVariableBlockDiagonal_MPIAIJ(Mat A, PetscInt nblocks, const PetscInt *bsizes, PetscScalar *diag)
2718: {
2719:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2721:   PetscFunctionBegin;
2722:   PetscCall(MatInvertVariableBlockDiagonal(a->A, nblocks, bsizes, diag));
2723:   PetscFunctionReturn(PETSC_SUCCESS);
2724: }

2726: static PetscErrorCode MatEliminateZeros_MPIAIJ(Mat A, PetscBool keep)
2727: {
2728:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;

2730:   PetscFunctionBegin;
2731:   PetscCall(MatEliminateZeros_SeqAIJ(a->A, keep));        // possibly keep zero diagonal coefficients
2732:   PetscCall(MatEliminateZeros_SeqAIJ(a->B, PETSC_FALSE)); // never keep zero diagonal coefficients
2733:   PetscFunctionReturn(PETSC_SUCCESS);
2734: }

2736: static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2737:                                        MatGetRow_MPIAIJ,
2738:                                        MatRestoreRow_MPIAIJ,
2739:                                        MatMult_MPIAIJ,
2740:                                        /* 4*/ MatMultAdd_MPIAIJ,
2741:                                        MatMultTranspose_MPIAIJ,
2742:                                        MatMultTransposeAdd_MPIAIJ,
2743:                                        NULL,
2744:                                        NULL,
2745:                                        NULL,
2746:                                        /*10*/ NULL,
2747:                                        NULL,
2748:                                        NULL,
2749:                                        MatSOR_MPIAIJ,
2750:                                        MatTranspose_MPIAIJ,
2751:                                        /*15*/ MatGetInfo_MPIAIJ,
2752:                                        MatEqual_MPIAIJ,
2753:                                        MatGetDiagonal_MPIAIJ,
2754:                                        MatDiagonalScale_MPIAIJ,
2755:                                        MatNorm_MPIAIJ,
2756:                                        /*20*/ MatAssemblyBegin_MPIAIJ,
2757:                                        MatAssemblyEnd_MPIAIJ,
2758:                                        MatSetOption_MPIAIJ,
2759:                                        MatZeroEntries_MPIAIJ,
2760:                                        /*24*/ MatZeroRows_MPIAIJ,
2761:                                        NULL,
2762:                                        NULL,
2763:                                        NULL,
2764:                                        NULL,
2765:                                        /*29*/ MatSetUp_MPI_Hash,
2766:                                        NULL,
2767:                                        NULL,
2768:                                        MatGetDiagonalBlock_MPIAIJ,
2769:                                        NULL,
2770:                                        /*34*/ MatDuplicate_MPIAIJ,
2771:                                        NULL,
2772:                                        NULL,
2773:                                        NULL,
2774:                                        NULL,
2775:                                        /*39*/ MatAXPY_MPIAIJ,
2776:                                        MatCreateSubMatrices_MPIAIJ,
2777:                                        MatIncreaseOverlap_MPIAIJ,
2778:                                        MatGetValues_MPIAIJ,
2779:                                        MatCopy_MPIAIJ,
2780:                                        /*44*/ MatGetRowMax_MPIAIJ,
2781:                                        MatScale_MPIAIJ,
2782:                                        MatShift_MPIAIJ,
2783:                                        MatDiagonalSet_MPIAIJ,
2784:                                        MatZeroRowsColumns_MPIAIJ,
2785:                                        /*49*/ MatSetRandom_MPIAIJ,
2786:                                        MatGetRowIJ_MPIAIJ,
2787:                                        MatRestoreRowIJ_MPIAIJ,
2788:                                        NULL,
2789:                                        NULL,
2790:                                        /*54*/ MatFDColoringCreate_MPIXAIJ,
2791:                                        NULL,
2792:                                        MatSetUnfactored_MPIAIJ,
2793:                                        MatPermute_MPIAIJ,
2794:                                        NULL,
2795:                                        /*59*/ MatCreateSubMatrix_MPIAIJ,
2796:                                        MatDestroy_MPIAIJ,
2797:                                        MatView_MPIAIJ,
2798:                                        NULL,
2799:                                        NULL,
2800:                                        /*64*/ NULL,
2801:                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2802:                                        NULL,
2803:                                        NULL,
2804:                                        NULL,
2805:                                        /*69*/ MatGetRowMaxAbs_MPIAIJ,
2806:                                        MatGetRowMinAbs_MPIAIJ,
2807:                                        NULL,
2808:                                        NULL,
2809:                                        NULL,
2810:                                        NULL,
2811:                                        /*75*/ MatFDColoringApply_AIJ,
2812:                                        MatSetFromOptions_MPIAIJ,
2813:                                        NULL,
2814:                                        NULL,
2815:                                        MatFindZeroDiagonals_MPIAIJ,
2816:                                        /*80*/ NULL,
2817:                                        NULL,
2818:                                        NULL,
2819:                                        /*83*/ MatLoad_MPIAIJ,
2820:                                        NULL,
2821:                                        NULL,
2822:                                        NULL,
2823:                                        NULL,
2824:                                        NULL,
2825:                                        /*89*/ NULL,
2826:                                        NULL,
2827:                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2828:                                        NULL,
2829:                                        NULL,
2830:                                        /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
2831:                                        NULL,
2832:                                        NULL,
2833:                                        NULL,
2834:                                        MatBindToCPU_MPIAIJ,
2835:                                        /*99*/ MatProductSetFromOptions_MPIAIJ,
2836:                                        NULL,
2837:                                        NULL,
2838:                                        MatConjugate_MPIAIJ,
2839:                                        NULL,
2840:                                        /*104*/ MatSetValuesRow_MPIAIJ,
2841:                                        MatRealPart_MPIAIJ,
2842:                                        MatImaginaryPart_MPIAIJ,
2843:                                        NULL,
2844:                                        NULL,
2845:                                        /*109*/ NULL,
2846:                                        NULL,
2847:                                        MatGetRowMin_MPIAIJ,
2848:                                        NULL,
2849:                                        MatMissingDiagonal_MPIAIJ,
2850:                                        /*114*/ MatGetSeqNonzeroStructure_MPIAIJ,
2851:                                        NULL,
2852:                                        MatGetGhosts_MPIAIJ,
2853:                                        NULL,
2854:                                        NULL,
2855:                                        /*119*/ MatMultDiagonalBlock_MPIAIJ,
2856:                                        NULL,
2857:                                        NULL,
2858:                                        NULL,
2859:                                        MatGetMultiProcBlock_MPIAIJ,
2860:                                        /*124*/ MatFindNonzeroRows_MPIAIJ,
2861:                                        MatGetColumnReductions_MPIAIJ,
2862:                                        MatInvertBlockDiagonal_MPIAIJ,
2863:                                        MatInvertVariableBlockDiagonal_MPIAIJ,
2864:                                        MatCreateSubMatricesMPI_MPIAIJ,
2865:                                        /*129*/ NULL,
2866:                                        NULL,
2867:                                        NULL,
2868:                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2869:                                        NULL,
2870:                                        /*134*/ NULL,
2871:                                        NULL,
2872:                                        NULL,
2873:                                        NULL,
2874:                                        NULL,
2875:                                        /*139*/ MatSetBlockSizes_MPIAIJ,
2876:                                        NULL,
2877:                                        NULL,
2878:                                        MatFDColoringSetUp_MPIXAIJ,
2879:                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2880:                                        MatCreateMPIMatConcatenateSeqMat_MPIAIJ,
2881:                                        /*145*/ NULL,
2882:                                        NULL,
2883:                                        NULL,
2884:                                        MatCreateGraph_Simple_AIJ,
2885:                                        NULL,
2886:                                        /*150*/ NULL,
2887:                                        MatEliminateZeros_MPIAIJ,
2888:                                        MatGetRowSumAbs_MPIAIJ,
2889:                                        NULL,
2890:                                        NULL,
2891:                                        /*155*/ NULL,
2892:                                        MatCopyHashToXAIJ_MPI_Hash};

2894: static PetscErrorCode MatStoreValues_MPIAIJ(Mat mat)
2895: {
2896:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2898:   PetscFunctionBegin;
2899:   PetscCall(MatStoreValues(aij->A));
2900:   PetscCall(MatStoreValues(aij->B));
2901:   PetscFunctionReturn(PETSC_SUCCESS);
2902: }

2904: static PetscErrorCode MatRetrieveValues_MPIAIJ(Mat mat)
2905: {
2906:   Mat_MPIAIJ *aij = (Mat_MPIAIJ *)mat->data;

2908:   PetscFunctionBegin;
2909:   PetscCall(MatRetrieveValues(aij->A));
2910:   PetscCall(MatRetrieveValues(aij->B));
2911:   PetscFunctionReturn(PETSC_SUCCESS);
2912: }

2914: PetscErrorCode MatMPIAIJSetPreallocation_MPIAIJ(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
2915: {
2916:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;
2917:   PetscMPIInt size;

2919:   PetscFunctionBegin;
2920:   if (B->hash_active) {
2921:     B->ops[0]      = b->cops;
2922:     B->hash_active = PETSC_FALSE;
2923:   }
2924:   PetscCall(PetscLayoutSetUp(B->rmap));
2925:   PetscCall(PetscLayoutSetUp(B->cmap));

2927: #if defined(PETSC_USE_CTABLE)
2928:   PetscCall(PetscHMapIDestroy(&b->colmap));
2929: #else
2930:   PetscCall(PetscFree(b->colmap));
2931: #endif
2932:   PetscCall(PetscFree(b->garray));
2933:   PetscCall(VecDestroy(&b->lvec));
2934:   PetscCall(VecScatterDestroy(&b->Mvctx));

2936:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

2938:   MatSeqXAIJGetOptions_Private(b->B);
2939:   PetscCall(MatDestroy(&b->B));
2940:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->B));
2941:   PetscCall(MatSetSizes(b->B, B->rmap->n, size > 1 ? B->cmap->N : 0, B->rmap->n, size > 1 ? B->cmap->N : 0));
2942:   PetscCall(MatSetBlockSizesFromMats(b->B, B, B));
2943:   PetscCall(MatSetType(b->B, MATSEQAIJ));
2944:   MatSeqXAIJRestoreOptions_Private(b->B);

2946:   MatSeqXAIJGetOptions_Private(b->A);
2947:   PetscCall(MatDestroy(&b->A));
2948:   PetscCall(MatCreate(PETSC_COMM_SELF, &b->A));
2949:   PetscCall(MatSetSizes(b->A, B->rmap->n, B->cmap->n, B->rmap->n, B->cmap->n));
2950:   PetscCall(MatSetBlockSizesFromMats(b->A, B, B));
2951:   PetscCall(MatSetType(b->A, MATSEQAIJ));
2952:   MatSeqXAIJRestoreOptions_Private(b->A);

2954:   PetscCall(MatSeqAIJSetPreallocation(b->A, d_nz, d_nnz));
2955:   PetscCall(MatSeqAIJSetPreallocation(b->B, o_nz, o_nnz));
2956:   B->preallocated  = PETSC_TRUE;
2957:   B->was_assembled = PETSC_FALSE;
2958:   B->assembled     = PETSC_FALSE;
2959:   PetscFunctionReturn(PETSC_SUCCESS);
2960: }

2962: static PetscErrorCode MatResetPreallocation_MPIAIJ(Mat B)
2963: {
2964:   Mat_MPIAIJ *b = (Mat_MPIAIJ *)B->data;

2966:   PetscFunctionBegin;
2968:   PetscCall(PetscLayoutSetUp(B->rmap));
2969:   PetscCall(PetscLayoutSetUp(B->cmap));

2971: #if defined(PETSC_USE_CTABLE)
2972:   PetscCall(PetscHMapIDestroy(&b->colmap));
2973: #else
2974:   PetscCall(PetscFree(b->colmap));
2975: #endif
2976:   PetscCall(PetscFree(b->garray));
2977:   PetscCall(VecDestroy(&b->lvec));
2978:   PetscCall(VecScatterDestroy(&b->Mvctx));

2980:   PetscCall(MatResetPreallocation(b->A));
2981:   PetscCall(MatResetPreallocation(b->B));
2982:   B->preallocated  = PETSC_TRUE;
2983:   B->was_assembled = PETSC_FALSE;
2984:   B->assembled     = PETSC_FALSE;
2985:   PetscFunctionReturn(PETSC_SUCCESS);
2986: }

2988: PetscErrorCode MatDuplicate_MPIAIJ(Mat matin, MatDuplicateOption cpvalues, Mat *newmat)
2989: {
2990:   Mat         mat;
2991:   Mat_MPIAIJ *a, *oldmat = (Mat_MPIAIJ *)matin->data;

2993:   PetscFunctionBegin;
2994:   *newmat = NULL;
2995:   PetscCall(MatCreate(PetscObjectComm((PetscObject)matin), &mat));
2996:   PetscCall(MatSetSizes(mat, matin->rmap->n, matin->cmap->n, matin->rmap->N, matin->cmap->N));
2997:   PetscCall(MatSetBlockSizesFromMats(mat, matin, matin));
2998:   PetscCall(MatSetType(mat, ((PetscObject)matin)->type_name));
2999:   a = (Mat_MPIAIJ *)mat->data;

3001:   mat->factortype = matin->factortype;
3002:   mat->assembled  = matin->assembled;
3003:   mat->insertmode = NOT_SET_VALUES;

3005:   a->size         = oldmat->size;
3006:   a->rank         = oldmat->rank;
3007:   a->donotstash   = oldmat->donotstash;
3008:   a->roworiented  = oldmat->roworiented;
3009:   a->rowindices   = NULL;
3010:   a->rowvalues    = NULL;
3011:   a->getrowactive = PETSC_FALSE;

3013:   PetscCall(PetscLayoutReference(matin->rmap, &mat->rmap));
3014:   PetscCall(PetscLayoutReference(matin->cmap, &mat->cmap));
3015:   if (matin->hash_active) {
3016:     PetscCall(MatSetUp(mat));
3017:   } else {
3018:     mat->preallocated = matin->preallocated;
3019:     if (oldmat->colmap) {
3020: #if defined(PETSC_USE_CTABLE)
3021:       PetscCall(PetscHMapIDuplicate(oldmat->colmap, &a->colmap));
3022: #else
3023:       PetscCall(PetscMalloc1(mat->cmap->N, &a->colmap));
3024:       PetscCall(PetscArraycpy(a->colmap, oldmat->colmap, mat->cmap->N));
3025: #endif
3026:     } else a->colmap = NULL;
3027:     if (oldmat->garray) {
3028:       PetscInt len;
3029:       len = oldmat->B->cmap->n;
3030:       PetscCall(PetscMalloc1(len + 1, &a->garray));
3031:       if (len) PetscCall(PetscArraycpy(a->garray, oldmat->garray, len));
3032:     } else a->garray = NULL;

3034:     /* It may happen MatDuplicate is called with a non-assembled matrix
3035:       In fact, MatDuplicate only requires the matrix to be preallocated
3036:       This may happen inside a DMCreateMatrix_Shell */
3037:     if (oldmat->lvec) PetscCall(VecDuplicate(oldmat->lvec, &a->lvec));
3038:     if (oldmat->Mvctx) {
3039:       a->Mvctx = oldmat->Mvctx;
3040:       PetscCall(PetscObjectReference((PetscObject)oldmat->Mvctx));
3041:     }
3042:     PetscCall(MatDuplicate(oldmat->A, cpvalues, &a->A));
3043:     PetscCall(MatDuplicate(oldmat->B, cpvalues, &a->B));
3044:   }
3045:   PetscCall(PetscFunctionListDuplicate(((PetscObject)matin)->qlist, &((PetscObject)mat)->qlist));
3046:   *newmat = mat;
3047:   PetscFunctionReturn(PETSC_SUCCESS);
3048: }

3050: PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3051: {
3052:   PetscBool isbinary, ishdf5;

3054:   PetscFunctionBegin;
3057:   /* force binary viewer to load .info file if it has not yet done so */
3058:   PetscCall(PetscViewerSetUp(viewer));
3059:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERBINARY, &isbinary));
3060:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
3061:   if (isbinary) {
3062:     PetscCall(MatLoad_MPIAIJ_Binary(newMat, viewer));
3063:   } else if (ishdf5) {
3064: #if defined(PETSC_HAVE_HDF5)
3065:     PetscCall(MatLoad_AIJ_HDF5(newMat, viewer));
3066: #else
3067:     SETERRQ(PetscObjectComm((PetscObject)newMat), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
3068: #endif
3069:   } else {
3070:     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);
3071:   }
3072:   PetscFunctionReturn(PETSC_SUCCESS);
3073: }

3075: PetscErrorCode MatLoad_MPIAIJ_Binary(Mat mat, PetscViewer viewer)
3076: {
3077:   PetscInt     header[4], M, N, m, nz, rows, cols, sum, i;
3078:   PetscInt    *rowidxs, *colidxs;
3079:   PetscScalar *matvals;

3081:   PetscFunctionBegin;
3082:   PetscCall(PetscViewerSetUp(viewer));

3084:   /* read in matrix header */
3085:   PetscCall(PetscViewerBinaryRead(viewer, header, 4, NULL, PETSC_INT));
3086:   PetscCheck(header[0] == MAT_FILE_CLASSID, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Not a matrix object in file");
3087:   M  = header[1];
3088:   N  = header[2];
3089:   nz = header[3];
3090:   PetscCheck(M >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix row size (%" PetscInt_FMT ") in file is negative", M);
3091:   PetscCheck(N >= 0, PetscObjectComm((PetscObject)viewer), PETSC_ERR_FILE_UNEXPECTED, "Matrix column size (%" PetscInt_FMT ") in file is negative", N);
3092:   PetscCheck(nz >= 0, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Matrix stored in special format on disk, cannot load as MPIAIJ");

3094:   /* set block sizes from the viewer's .info file */
3095:   PetscCall(MatLoad_Binary_BlockSizes(mat, viewer));
3096:   /* set global sizes if not set already */
3097:   if (mat->rmap->N < 0) mat->rmap->N = M;
3098:   if (mat->cmap->N < 0) mat->cmap->N = N;
3099:   PetscCall(PetscLayoutSetUp(mat->rmap));
3100:   PetscCall(PetscLayoutSetUp(mat->cmap));

3102:   /* check if the matrix sizes are correct */
3103:   PetscCall(MatGetSize(mat, &rows, &cols));
3104:   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);

3106:   /* read in row lengths and build row indices */
3107:   PetscCall(MatGetLocalSize(mat, &m, NULL));
3108:   PetscCall(PetscMalloc1(m + 1, &rowidxs));
3109:   PetscCall(PetscViewerBinaryReadAll(viewer, rowidxs + 1, m, PETSC_DECIDE, M, PETSC_INT));
3110:   rowidxs[0] = 0;
3111:   for (i = 0; i < m; i++) rowidxs[i + 1] += rowidxs[i];
3112:   if (nz != PETSC_INT_MAX) {
3113:     PetscCallMPI(MPIU_Allreduce(&rowidxs[m], &sum, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)viewer)));
3114:     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);
3115:   }

3117:   /* read in column indices and matrix values */
3118:   PetscCall(PetscMalloc2(rowidxs[m], &colidxs, rowidxs[m], &matvals));
3119:   PetscCall(PetscViewerBinaryReadAll(viewer, colidxs, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_INT));
3120:   PetscCall(PetscViewerBinaryReadAll(viewer, matvals, rowidxs[m], PETSC_DETERMINE, PETSC_DETERMINE, PETSC_SCALAR));
3121:   /* store matrix indices and values */
3122:   PetscCall(MatMPIAIJSetPreallocationCSR(mat, rowidxs, colidxs, matvals));
3123:   PetscCall(PetscFree(rowidxs));
3124:   PetscCall(PetscFree2(colidxs, matvals));
3125:   PetscFunctionReturn(PETSC_SUCCESS);
3126: }

3128: /* Not scalable because of ISAllGather() unless getting all columns. */
3129: static PetscErrorCode ISGetSeqIS_Private(Mat mat, IS iscol, IS *isseq)
3130: {
3131:   IS          iscol_local;
3132:   PetscBool   isstride;
3133:   PetscMPIInt lisstride = 0, gisstride;

3135:   PetscFunctionBegin;
3136:   /* check if we are grabbing all columns*/
3137:   PetscCall(PetscObjectTypeCompare((PetscObject)iscol, ISSTRIDE, &isstride));

3139:   if (isstride) {
3140:     PetscInt start, len, mstart, mlen;
3141:     PetscCall(ISStrideGetInfo(iscol, &start, NULL));
3142:     PetscCall(ISGetLocalSize(iscol, &len));
3143:     PetscCall(MatGetOwnershipRangeColumn(mat, &mstart, &mlen));
3144:     if (mstart == start && mlen - mstart == len) lisstride = 1;
3145:   }

3147:   PetscCallMPI(MPIU_Allreduce(&lisstride, &gisstride, 1, MPI_INT, MPI_MIN, PetscObjectComm((PetscObject)mat)));
3148:   if (gisstride) {
3149:     PetscInt N;
3150:     PetscCall(MatGetSize(mat, NULL, &N));
3151:     PetscCall(ISCreateStride(PETSC_COMM_SELF, N, 0, 1, &iscol_local));
3152:     PetscCall(ISSetIdentity(iscol_local));
3153:     PetscCall(PetscInfo(mat, "Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n"));
3154:   } else {
3155:     PetscInt cbs;
3156:     PetscCall(ISGetBlockSize(iscol, &cbs));
3157:     PetscCall(ISAllGather(iscol, &iscol_local));
3158:     PetscCall(ISSetBlockSize(iscol_local, cbs));
3159:   }

3161:   *isseq = iscol_local;
3162:   PetscFunctionReturn(PETSC_SUCCESS);
3163: }

3165: /*
3166:  Used by MatCreateSubMatrix_MPIAIJ_SameRowColDist() to avoid ISAllGather() and global size of iscol_local
3167:  (see MatCreateSubMatrix_MPIAIJ_nonscalable)

3169:  Input Parameters:
3170: +   mat - matrix
3171: .   isrow - parallel row index set; its local indices are a subset of local columns of `mat`,
3172:            i.e., mat->rstart <= isrow[i] < mat->rend
3173: -   iscol - parallel column index set; its local indices are a subset of local columns of `mat`,
3174:            i.e., mat->cstart <= iscol[i] < mat->cend

3176:  Output Parameters:
3177: +   isrow_d - sequential row index set for retrieving mat->A
3178: .   iscol_d - sequential  column index set for retrieving mat->A
3179: .   iscol_o - sequential column index set for retrieving mat->B
3180: -   garray - column map; garray[i] indicates global location of iscol_o[i] in `iscol`
3181:  */
3182: static PetscErrorCode ISGetSeqIS_SameColDist_Private(Mat mat, IS isrow, IS iscol, IS *isrow_d, IS *iscol_d, IS *iscol_o, PetscInt *garray[])
3183: {
3184:   Vec             x, cmap;
3185:   const PetscInt *is_idx;
3186:   PetscScalar    *xarray, *cmaparray;
3187:   PetscInt        ncols, isstart, *idx, m, rstart, *cmap1, count;
3188:   Mat_MPIAIJ     *a    = (Mat_MPIAIJ *)mat->data;
3189:   Mat             B    = a->B;
3190:   Vec             lvec = a->lvec, lcmap;
3191:   PetscInt        i, cstart, cend, Bn = B->cmap->N;
3192:   MPI_Comm        comm;
3193:   VecScatter      Mvctx = a->Mvctx;

3195:   PetscFunctionBegin;
3196:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3197:   PetscCall(ISGetLocalSize(iscol, &ncols));

3199:   /* (1) iscol is a sub-column vector of mat, pad it with '-1.' to form a full vector x */
3200:   PetscCall(MatCreateVecs(mat, &x, NULL));
3201:   PetscCall(VecSet(x, -1.0));
3202:   PetscCall(VecDuplicate(x, &cmap));
3203:   PetscCall(VecSet(cmap, -1.0));

3205:   /* Get start indices */
3206:   PetscCallMPI(MPI_Scan(&ncols, &isstart, 1, MPIU_INT, MPI_SUM, comm));
3207:   isstart -= ncols;
3208:   PetscCall(MatGetOwnershipRangeColumn(mat, &cstart, &cend));

3210:   PetscCall(ISGetIndices(iscol, &is_idx));
3211:   PetscCall(VecGetArray(x, &xarray));
3212:   PetscCall(VecGetArray(cmap, &cmaparray));
3213:   PetscCall(PetscMalloc1(ncols, &idx));
3214:   for (i = 0; i < ncols; i++) {
3215:     xarray[is_idx[i] - cstart]    = (PetscScalar)is_idx[i];
3216:     cmaparray[is_idx[i] - cstart] = i + isstart;        /* global index of iscol[i] */
3217:     idx[i]                        = is_idx[i] - cstart; /* local index of iscol[i]  */
3218:   }
3219:   PetscCall(VecRestoreArray(x, &xarray));
3220:   PetscCall(VecRestoreArray(cmap, &cmaparray));
3221:   PetscCall(ISRestoreIndices(iscol, &is_idx));

3223:   /* Get iscol_d */
3224:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, iscol_d));
3225:   PetscCall(ISGetBlockSize(iscol, &i));
3226:   PetscCall(ISSetBlockSize(*iscol_d, i));

3228:   /* Get isrow_d */
3229:   PetscCall(ISGetLocalSize(isrow, &m));
3230:   rstart = mat->rmap->rstart;
3231:   PetscCall(PetscMalloc1(m, &idx));
3232:   PetscCall(ISGetIndices(isrow, &is_idx));
3233:   for (i = 0; i < m; i++) idx[i] = is_idx[i] - rstart;
3234:   PetscCall(ISRestoreIndices(isrow, &is_idx));

3236:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx, PETSC_OWN_POINTER, isrow_d));
3237:   PetscCall(ISGetBlockSize(isrow, &i));
3238:   PetscCall(ISSetBlockSize(*isrow_d, i));

3240:   /* (2) Scatter x and cmap using aij->Mvctx to get their off-process portions (see MatMult_MPIAIJ) */
3241:   PetscCall(VecScatterBegin(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));
3242:   PetscCall(VecScatterEnd(Mvctx, x, lvec, INSERT_VALUES, SCATTER_FORWARD));

3244:   PetscCall(VecDuplicate(lvec, &lcmap));

3246:   PetscCall(VecScatterBegin(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));
3247:   PetscCall(VecScatterEnd(Mvctx, cmap, lcmap, INSERT_VALUES, SCATTER_FORWARD));

3249:   /* (3) create sequential iscol_o (a subset of iscol) and isgarray */
3250:   /* off-process column indices */
3251:   count = 0;
3252:   PetscCall(PetscMalloc1(Bn, &idx));
3253:   PetscCall(PetscMalloc1(Bn, &cmap1));

3255:   PetscCall(VecGetArray(lvec, &xarray));
3256:   PetscCall(VecGetArray(lcmap, &cmaparray));
3257:   for (i = 0; i < Bn; i++) {
3258:     if (PetscRealPart(xarray[i]) > -1.0) {
3259:       idx[count]   = i;                                     /* local column index in off-diagonal part B */
3260:       cmap1[count] = (PetscInt)PetscRealPart(cmaparray[i]); /* column index in submat */
3261:       count++;
3262:     }
3263:   }
3264:   PetscCall(VecRestoreArray(lvec, &xarray));
3265:   PetscCall(VecRestoreArray(lcmap, &cmaparray));

3267:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_COPY_VALUES, iscol_o));
3268:   /* cannot ensure iscol_o has same blocksize as iscol! */

3270:   PetscCall(PetscFree(idx));
3271:   *garray = cmap1;

3273:   PetscCall(VecDestroy(&x));
3274:   PetscCall(VecDestroy(&cmap));
3275:   PetscCall(VecDestroy(&lcmap));
3276:   PetscFunctionReturn(PETSC_SUCCESS);
3277: }

3279: /* isrow and iscol have same processor distribution as mat, output *submat is a submatrix of local mat */
3280: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowColDist(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *submat)
3281: {
3282:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)mat->data, *asub;
3283:   Mat         M = NULL;
3284:   MPI_Comm    comm;
3285:   IS          iscol_d, isrow_d, iscol_o;
3286:   Mat         Asub = NULL, Bsub = NULL;
3287:   PetscInt    n;

3289:   PetscFunctionBegin;
3290:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));

3292:   if (call == MAT_REUSE_MATRIX) {
3293:     /* Retrieve isrow_d, iscol_d and iscol_o from submat */
3294:     PetscCall(PetscObjectQuery((PetscObject)*submat, "isrow_d", (PetscObject *)&isrow_d));
3295:     PetscCheck(isrow_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "isrow_d passed in was not used before, cannot reuse");

3297:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_d", (PetscObject *)&iscol_d));
3298:     PetscCheck(iscol_d, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_d passed in was not used before, cannot reuse");

3300:     PetscCall(PetscObjectQuery((PetscObject)*submat, "iscol_o", (PetscObject *)&iscol_o));
3301:     PetscCheck(iscol_o, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "iscol_o passed in was not used before, cannot reuse");

3303:     /* Update diagonal and off-diagonal portions of submat */
3304:     asub = (Mat_MPIAIJ *)(*submat)->data;
3305:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->A));
3306:     PetscCall(ISGetLocalSize(iscol_o, &n));
3307:     if (n) PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_REUSE_MATRIX, &asub->B));
3308:     PetscCall(MatAssemblyBegin(*submat, MAT_FINAL_ASSEMBLY));
3309:     PetscCall(MatAssemblyEnd(*submat, MAT_FINAL_ASSEMBLY));

3311:   } else { /* call == MAT_INITIAL_MATRIX) */
3312:     PetscInt *garray;
3313:     PetscInt  BsubN;

3315:     /* Create isrow_d, iscol_d, iscol_o and isgarray (replace isgarray with array?) */
3316:     PetscCall(ISGetSeqIS_SameColDist_Private(mat, isrow, iscol, &isrow_d, &iscol_d, &iscol_o, &garray));

3318:     /* Create local submatrices Asub and Bsub */
3319:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->A, isrow_d, iscol_d, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Asub));
3320:     PetscCall(MatCreateSubMatrix_SeqAIJ(a->B, isrow_d, iscol_o, PETSC_DECIDE, MAT_INITIAL_MATRIX, &Bsub));

3322:     /* Create submatrix M */
3323:     PetscCall(MatCreateMPIAIJWithSeqAIJ(comm, Asub, Bsub, garray, &M));

3325:     /* If Bsub has empty columns, compress iscol_o such that it will retrieve condensed Bsub from a->B during reuse */
3326:     asub = (Mat_MPIAIJ *)M->data;

3328:     PetscCall(ISGetLocalSize(iscol_o, &BsubN));
3329:     n = asub->B->cmap->N;
3330:     if (BsubN > n) {
3331:       /* This case can be tested using ~petsc/src/tao/bound/tutorials/runplate2_3 */
3332:       const PetscInt *idx;
3333:       PetscInt        i, j, *idx_new, *subgarray = asub->garray;
3334:       PetscCall(PetscInfo(M, "submatrix Bn %" PetscInt_FMT " != BsubN %" PetscInt_FMT ", update iscol_o\n", n, BsubN));

3336:       PetscCall(PetscMalloc1(n, &idx_new));
3337:       j = 0;
3338:       PetscCall(ISGetIndices(iscol_o, &idx));
3339:       for (i = 0; i < n; i++) {
3340:         if (j >= BsubN) break;
3341:         while (subgarray[i] > garray[j]) j++;

3343:         if (subgarray[i] == garray[j]) {
3344:           idx_new[i] = idx[j++];
3345:         } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "subgarray[%" PetscInt_FMT "]=%" PetscInt_FMT " cannot < garray[%" PetscInt_FMT "]=%" PetscInt_FMT, i, subgarray[i], j, garray[j]);
3346:       }
3347:       PetscCall(ISRestoreIndices(iscol_o, &idx));

3349:       PetscCall(ISDestroy(&iscol_o));
3350:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, idx_new, PETSC_OWN_POINTER, &iscol_o));

3352:     } else if (BsubN < n) {
3353:       SETERRQ(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);
3354:     }

3356:     PetscCall(PetscFree(garray));
3357:     *submat = M;

3359:     /* Save isrow_d, iscol_d and iscol_o used in processor for next request */
3360:     PetscCall(PetscObjectCompose((PetscObject)M, "isrow_d", (PetscObject)isrow_d));
3361:     PetscCall(ISDestroy(&isrow_d));

3363:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_d", (PetscObject)iscol_d));
3364:     PetscCall(ISDestroy(&iscol_d));

3366:     PetscCall(PetscObjectCompose((PetscObject)M, "iscol_o", (PetscObject)iscol_o));
3367:     PetscCall(ISDestroy(&iscol_o));
3368:   }
3369:   PetscFunctionReturn(PETSC_SUCCESS);
3370: }

3372: PetscErrorCode MatCreateSubMatrix_MPIAIJ(Mat mat, IS isrow, IS iscol, MatReuse call, Mat *newmat)
3373: {
3374:   IS        iscol_local = NULL, isrow_d;
3375:   PetscInt  csize;
3376:   PetscInt  n, i, j, start, end;
3377:   PetscBool sameRowDist = PETSC_FALSE, sameDist[2], tsameDist[2];
3378:   MPI_Comm  comm;

3380:   PetscFunctionBegin;
3381:   /* If isrow has same processor distribution as mat,
3382:      call MatCreateSubMatrix_MPIAIJ_SameRowDist() to avoid using a hash table with global size of iscol */
3383:   if (call == MAT_REUSE_MATRIX) {
3384:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "isrow_d", (PetscObject *)&isrow_d));
3385:     if (isrow_d) {
3386:       sameRowDist  = PETSC_TRUE;
3387:       tsameDist[1] = PETSC_TRUE; /* sameColDist */
3388:     } else {
3389:       PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_local));
3390:       if (iscol_local) {
3391:         sameRowDist  = PETSC_TRUE;
3392:         tsameDist[1] = PETSC_FALSE; /* !sameColDist */
3393:       }
3394:     }
3395:   } else {
3396:     /* Check if isrow has same processor distribution as mat */
3397:     sameDist[0] = PETSC_FALSE;
3398:     PetscCall(ISGetLocalSize(isrow, &n));
3399:     if (!n) {
3400:       sameDist[0] = PETSC_TRUE;
3401:     } else {
3402:       PetscCall(ISGetMinMax(isrow, &i, &j));
3403:       PetscCall(MatGetOwnershipRange(mat, &start, &end));
3404:       if (i >= start && j < end) sameDist[0] = PETSC_TRUE;
3405:     }

3407:     /* Check if iscol has same processor distribution as mat */
3408:     sameDist[1] = PETSC_FALSE;
3409:     PetscCall(ISGetLocalSize(iscol, &n));
3410:     if (!n) {
3411:       sameDist[1] = PETSC_TRUE;
3412:     } else {
3413:       PetscCall(ISGetMinMax(iscol, &i, &j));
3414:       PetscCall(MatGetOwnershipRangeColumn(mat, &start, &end));
3415:       if (i >= start && j < end) sameDist[1] = PETSC_TRUE;
3416:     }

3418:     PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3419:     PetscCallMPI(MPIU_Allreduce(&sameDist, &tsameDist, 2, MPIU_BOOL, MPI_LAND, comm));
3420:     sameRowDist = tsameDist[0];
3421:   }

3423:   if (sameRowDist) {
3424:     if (tsameDist[1]) { /* sameRowDist & sameColDist */
3425:       /* isrow and iscol have same processor distribution as mat */
3426:       PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowColDist(mat, isrow, iscol, call, newmat));
3427:       PetscFunctionReturn(PETSC_SUCCESS);
3428:     } else { /* sameRowDist */
3429:       /* isrow has same processor distribution as mat */
3430:       if (call == MAT_INITIAL_MATRIX) {
3431:         PetscBool sorted;
3432:         PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3433:         PetscCall(ISGetLocalSize(iscol_local, &n)); /* local size of iscol_local = global columns of newmat */
3434:         PetscCall(ISGetSize(iscol, &i));
3435:         PetscCheck(n == i, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "n %" PetscInt_FMT " != size of iscol %" PetscInt_FMT, n, i);

3437:         PetscCall(ISSorted(iscol_local, &sorted));
3438:         if (sorted) {
3439:           /* MatCreateSubMatrix_MPIAIJ_SameRowDist() requires iscol_local be sorted; it can have duplicate indices */
3440:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, iscol_local, MAT_INITIAL_MATRIX, newmat));
3441:           PetscFunctionReturn(PETSC_SUCCESS);
3442:         }
3443:       } else { /* call == MAT_REUSE_MATRIX */
3444:         IS iscol_sub;
3445:         PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3446:         if (iscol_sub) {
3447:           PetscCall(MatCreateSubMatrix_MPIAIJ_SameRowDist(mat, isrow, iscol, NULL, call, newmat));
3448:           PetscFunctionReturn(PETSC_SUCCESS);
3449:         }
3450:       }
3451:     }
3452:   }

3454:   /* General case: iscol -> iscol_local which has global size of iscol */
3455:   if (call == MAT_REUSE_MATRIX) {
3456:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "ISAllGather", (PetscObject *)&iscol_local));
3457:     PetscCheck(iscol_local, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3458:   } else {
3459:     if (!iscol_local) PetscCall(ISGetSeqIS_Private(mat, iscol, &iscol_local));
3460:   }

3462:   PetscCall(ISGetLocalSize(iscol, &csize));
3463:   PetscCall(MatCreateSubMatrix_MPIAIJ_nonscalable(mat, isrow, iscol_local, csize, call, newmat));

3465:   if (call == MAT_INITIAL_MATRIX) {
3466:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3467:     PetscCall(ISDestroy(&iscol_local));
3468:   }
3469:   PetscFunctionReturn(PETSC_SUCCESS);
3470: }

3472: /*@C
3473:   MatCreateMPIAIJWithSeqAIJ - creates a `MATMPIAIJ` matrix using `MATSEQAIJ` matrices that contain the "diagonal"
3474:   and "off-diagonal" part of the matrix in CSR format.

3476:   Collective

3478:   Input Parameters:
3479: + comm   - MPI communicator
3480: . A      - "diagonal" portion of matrix
3481: . B      - "off-diagonal" portion of matrix, may have empty columns, will be destroyed by this routine
3482: - garray - global index of `B` columns

3484:   Output Parameter:
3485: . mat - the matrix, with input `A` as its local diagonal matrix

3487:   Level: advanced

3489:   Notes:
3490:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix.

3492:   `A` becomes part of output mat, `B` is destroyed by this routine. The user cannot use `A` and `B` anymore.

3494: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MATSEQAIJ`, `MatCreateMPIAIJWithSplitArrays()`
3495: @*/
3496: PetscErrorCode MatCreateMPIAIJWithSeqAIJ(MPI_Comm comm, Mat A, Mat B, const PetscInt garray[], Mat *mat)
3497: {
3498:   Mat_MPIAIJ        *maij;
3499:   Mat_SeqAIJ        *b  = (Mat_SeqAIJ *)B->data, *bnew;
3500:   PetscInt          *oi = b->i, *oj = b->j, i, nz, col;
3501:   const PetscScalar *oa;
3502:   Mat                Bnew;
3503:   PetscInt           m, n, N;
3504:   MatType            mpi_mat_type;

3506:   PetscFunctionBegin;
3507:   PetscCall(MatCreate(comm, mat));
3508:   PetscCall(MatGetSize(A, &m, &n));
3509:   PetscCheck(m == B->rmap->N, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Am %" PetscInt_FMT " != Bm %" PetscInt_FMT, m, B->rmap->N);
3510:   PetscCheck(PetscAbs(A->rmap->bs) == PetscAbs(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);
3511:   /* remove check below; When B is created using iscol_o from ISGetSeqIS_SameColDist_Private(), its bs may not be same as A */
3512:   /* PetscCheck(A->cmap->bs == B->cmap->bs,PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"A column bs %" PetscInt_FMT " != B column bs %" PetscInt_FMT,A->cmap->bs,B->cmap->bs); */

3514:   /* Get global columns of mat */
3515:   PetscCallMPI(MPIU_Allreduce(&n, &N, 1, MPIU_INT, MPI_SUM, comm));

3517:   PetscCall(MatSetSizes(*mat, m, n, PETSC_DECIDE, N));
3518:   /* Determine the type of MPI matrix that should be created from the type of matrix A, which holds the "diagonal" portion. */
3519:   PetscCall(MatGetMPIMatType_Private(A, &mpi_mat_type));
3520:   PetscCall(MatSetType(*mat, mpi_mat_type));

3522:   if (A->rmap->bs > 1 || A->cmap->bs > 1) PetscCall(MatSetBlockSizes(*mat, A->rmap->bs, A->cmap->bs));
3523:   maij = (Mat_MPIAIJ *)(*mat)->data;

3525:   (*mat)->preallocated = PETSC_TRUE;

3527:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
3528:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

3530:   /* Set A as diagonal portion of *mat */
3531:   maij->A = A;

3533:   nz = oi[m];
3534:   for (i = 0; i < nz; i++) {
3535:     col   = oj[i];
3536:     oj[i] = garray[col];
3537:   }

3539:   /* Set Bnew as off-diagonal portion of *mat */
3540:   PetscCall(MatSeqAIJGetArrayRead(B, &oa));
3541:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, N, oi, oj, (PetscScalar *)oa, &Bnew));
3542:   PetscCall(MatSeqAIJRestoreArrayRead(B, &oa));
3543:   bnew        = (Mat_SeqAIJ *)Bnew->data;
3544:   bnew->maxnz = b->maxnz; /* allocated nonzeros of B */
3545:   maij->B     = Bnew;

3547:   PetscCheck(B->rmap->N == Bnew->rmap->N, PETSC_COMM_SELF, PETSC_ERR_PLIB, "BN %" PetscInt_FMT " != BnewN %" PetscInt_FMT, B->rmap->N, Bnew->rmap->N);

3549:   b->free_a  = PETSC_FALSE;
3550:   b->free_ij = PETSC_FALSE;
3551:   PetscCall(MatDestroy(&B));

3553:   bnew->free_a  = PETSC_TRUE;
3554:   bnew->free_ij = PETSC_TRUE;

3556:   /* condense columns of maij->B */
3557:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
3558:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
3559:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
3560:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
3561:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3562:   PetscFunctionReturn(PETSC_SUCCESS);
3563: }

3565: extern PetscErrorCode MatCreateSubMatrices_MPIAIJ_SingleIS_Local(Mat, PetscInt, const IS[], const IS[], MatReuse, PetscBool, Mat *);

3567: PetscErrorCode MatCreateSubMatrix_MPIAIJ_SameRowDist(Mat mat, IS isrow, IS iscol, IS iscol_local, MatReuse call, Mat *newmat)
3568: {
3569:   PetscInt        i, m, n, rstart, row, rend, nz, j, bs, cbs;
3570:   PetscInt       *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3571:   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)mat->data;
3572:   Mat             M, Msub, B = a->B;
3573:   MatScalar      *aa;
3574:   Mat_SeqAIJ     *aij;
3575:   PetscInt       *garray = a->garray, *colsub, Ncols;
3576:   PetscInt        count, Bn = B->cmap->N, cstart = mat->cmap->rstart, cend = mat->cmap->rend;
3577:   IS              iscol_sub, iscmap;
3578:   const PetscInt *is_idx, *cmap;
3579:   PetscBool       allcolumns = PETSC_FALSE;
3580:   MPI_Comm        comm;

3582:   PetscFunctionBegin;
3583:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3584:   if (call == MAT_REUSE_MATRIX) {
3585:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubIScol", (PetscObject *)&iscol_sub));
3586:     PetscCheck(iscol_sub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "SubIScol passed in was not used before, cannot reuse");
3587:     PetscCall(ISGetLocalSize(iscol_sub, &count));

3589:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "Subcmap", (PetscObject *)&iscmap));
3590:     PetscCheck(iscmap, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Subcmap passed in was not used before, cannot reuse");

3592:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Msub));
3593:     PetscCheck(Msub, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");

3595:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_REUSE_MATRIX, PETSC_FALSE, &Msub));

3597:   } else { /* call == MAT_INITIAL_MATRIX) */
3598:     PetscBool flg;

3600:     PetscCall(ISGetLocalSize(iscol, &n));
3601:     PetscCall(ISGetSize(iscol, &Ncols));

3603:     /* (1) iscol -> nonscalable iscol_local */
3604:     /* Check for special case: each processor gets entire matrix columns */
3605:     PetscCall(ISIdentity(iscol_local, &flg));
3606:     if (flg && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3607:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));
3608:     if (allcolumns) {
3609:       iscol_sub = iscol_local;
3610:       PetscCall(PetscObjectReference((PetscObject)iscol_local));
3611:       PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &iscmap));

3613:     } else {
3614:       /* (2) iscol_local -> iscol_sub and iscmap. Implementation below requires iscol_local be sorted, it can have duplicate indices */
3615:       PetscInt *idx, *cmap1, k;
3616:       PetscCall(PetscMalloc1(Ncols, &idx));
3617:       PetscCall(PetscMalloc1(Ncols, &cmap1));
3618:       PetscCall(ISGetIndices(iscol_local, &is_idx));
3619:       count = 0;
3620:       k     = 0;
3621:       for (i = 0; i < Ncols; i++) {
3622:         j = is_idx[i];
3623:         if (j >= cstart && j < cend) {
3624:           /* diagonal part of mat */
3625:           idx[count]     = j;
3626:           cmap1[count++] = i; /* column index in submat */
3627:         } else if (Bn) {
3628:           /* off-diagonal part of mat */
3629:           if (j == garray[k]) {
3630:             idx[count]     = j;
3631:             cmap1[count++] = i; /* column index in submat */
3632:           } else if (j > garray[k]) {
3633:             while (j > garray[k] && k < Bn - 1) k++;
3634:             if (j == garray[k]) {
3635:               idx[count]     = j;
3636:               cmap1[count++] = i; /* column index in submat */
3637:             }
3638:           }
3639:         }
3640:       }
3641:       PetscCall(ISRestoreIndices(iscol_local, &is_idx));

3643:       PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count, idx, PETSC_OWN_POINTER, &iscol_sub));
3644:       PetscCall(ISGetBlockSize(iscol, &cbs));
3645:       PetscCall(ISSetBlockSize(iscol_sub, cbs));

3647:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)iscol_local), count, cmap1, PETSC_OWN_POINTER, &iscmap));
3648:     }

3650:     /* (3) Create sequential Msub */
3651:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol_sub, MAT_INITIAL_MATRIX, allcolumns, &Msub));
3652:   }

3654:   PetscCall(ISGetLocalSize(iscol_sub, &count));
3655:   aij = (Mat_SeqAIJ *)Msub->data;
3656:   ii  = aij->i;
3657:   PetscCall(ISGetIndices(iscmap, &cmap));

3659:   /*
3660:       m - number of local rows
3661:       Ncols - number of columns (same on all processors)
3662:       rstart - first row in new global matrix generated
3663:   */
3664:   PetscCall(MatGetSize(Msub, &m, NULL));

3666:   if (call == MAT_INITIAL_MATRIX) {
3667:     /* (4) Create parallel newmat */
3668:     PetscMPIInt rank, size;
3669:     PetscInt    csize;

3671:     PetscCallMPI(MPI_Comm_size(comm, &size));
3672:     PetscCallMPI(MPI_Comm_rank(comm, &rank));

3674:     /*
3675:         Determine the number of non-zeros in the diagonal and off-diagonal
3676:         portions of the matrix in order to do correct preallocation
3677:     */

3679:     /* first get start and end of "diagonal" columns */
3680:     PetscCall(ISGetLocalSize(iscol, &csize));
3681:     if (csize == PETSC_DECIDE) {
3682:       PetscCall(ISGetSize(isrow, &mglobal));
3683:       if (mglobal == Ncols) { /* square matrix */
3684:         nlocal = m;
3685:       } else {
3686:         nlocal = Ncols / size + ((Ncols % size) > rank);
3687:       }
3688:     } else {
3689:       nlocal = csize;
3690:     }
3691:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3692:     rstart = rend - nlocal;
3693:     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);

3695:     /* next, compute all the lengths */
3696:     jj = aij->j;
3697:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3698:     olens = dlens + m;
3699:     for (i = 0; i < m; i++) {
3700:       jend = ii[i + 1] - ii[i];
3701:       olen = 0;
3702:       dlen = 0;
3703:       for (j = 0; j < jend; j++) {
3704:         if (cmap[*jj] < rstart || cmap[*jj] >= rend) olen++;
3705:         else dlen++;
3706:         jj++;
3707:       }
3708:       olens[i] = olen;
3709:       dlens[i] = dlen;
3710:     }

3712:     PetscCall(ISGetBlockSize(isrow, &bs));
3713:     PetscCall(ISGetBlockSize(iscol, &cbs));

3715:     PetscCall(MatCreate(comm, &M));
3716:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, Ncols));
3717:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3718:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3719:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3720:     PetscCall(PetscFree(dlens));

3722:   } else { /* call == MAT_REUSE_MATRIX */
3723:     M = *newmat;
3724:     PetscCall(MatGetLocalSize(M, &i, NULL));
3725:     PetscCheck(i == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3726:     PetscCall(MatZeroEntries(M));
3727:     /*
3728:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3729:        rather than the slower MatSetValues().
3730:     */
3731:     M->was_assembled = PETSC_TRUE;
3732:     M->assembled     = PETSC_FALSE;
3733:   }

3735:   /* (5) Set values of Msub to *newmat */
3736:   PetscCall(PetscMalloc1(count, &colsub));
3737:   PetscCall(MatGetOwnershipRange(M, &rstart, NULL));

3739:   jj = aij->j;
3740:   PetscCall(MatSeqAIJGetArrayRead(Msub, (const PetscScalar **)&aa));
3741:   for (i = 0; i < m; i++) {
3742:     row = rstart + i;
3743:     nz  = ii[i + 1] - ii[i];
3744:     for (j = 0; j < nz; j++) colsub[j] = cmap[jj[j]];
3745:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, colsub, aa, INSERT_VALUES));
3746:     jj += nz;
3747:     aa += nz;
3748:   }
3749:   PetscCall(MatSeqAIJRestoreArrayRead(Msub, (const PetscScalar **)&aa));
3750:   PetscCall(ISRestoreIndices(iscmap, &cmap));

3752:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3753:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));

3755:   PetscCall(PetscFree(colsub));

3757:   /* save Msub, iscol_sub and iscmap used in processor for next request */
3758:   if (call == MAT_INITIAL_MATRIX) {
3759:     *newmat = M;
3760:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubMatrix", (PetscObject)Msub));
3761:     PetscCall(MatDestroy(&Msub));

3763:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "SubIScol", (PetscObject)iscol_sub));
3764:     PetscCall(ISDestroy(&iscol_sub));

3766:     PetscCall(PetscObjectCompose((PetscObject)*newmat, "Subcmap", (PetscObject)iscmap));
3767:     PetscCall(ISDestroy(&iscmap));

3769:     if (iscol_local) {
3770:       PetscCall(PetscObjectCompose((PetscObject)*newmat, "ISAllGather", (PetscObject)iscol_local));
3771:       PetscCall(ISDestroy(&iscol_local));
3772:     }
3773:   }
3774:   PetscFunctionReturn(PETSC_SUCCESS);
3775: }

3777: /*
3778:     Not great since it makes two copies of the submatrix, first an SeqAIJ
3779:   in local and then by concatenating the local matrices the end result.
3780:   Writing it directly would be much like MatCreateSubMatrices_MPIAIJ()

3782:   This requires a sequential iscol with all indices.
3783: */
3784: PetscErrorCode MatCreateSubMatrix_MPIAIJ_nonscalable(Mat mat, IS isrow, IS iscol, PetscInt csize, MatReuse call, Mat *newmat)
3785: {
3786:   PetscMPIInt rank, size;
3787:   PetscInt    i, m, n, rstart, row, rend, nz, *cwork, j, bs, cbs;
3788:   PetscInt   *ii, *jj, nlocal, *dlens, *olens, dlen, olen, jend, mglobal;
3789:   Mat         M, Mreuse;
3790:   MatScalar  *aa, *vwork;
3791:   MPI_Comm    comm;
3792:   Mat_SeqAIJ *aij;
3793:   PetscBool   colflag, allcolumns = PETSC_FALSE;

3795:   PetscFunctionBegin;
3796:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
3797:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
3798:   PetscCallMPI(MPI_Comm_size(comm, &size));

3800:   /* Check for special case: each processor gets entire matrix columns */
3801:   PetscCall(ISIdentity(iscol, &colflag));
3802:   PetscCall(ISGetLocalSize(iscol, &n));
3803:   if (colflag && n == mat->cmap->N) allcolumns = PETSC_TRUE;
3804:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &allcolumns, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)mat)));

3806:   if (call == MAT_REUSE_MATRIX) {
3807:     PetscCall(PetscObjectQuery((PetscObject)*newmat, "SubMatrix", (PetscObject *)&Mreuse));
3808:     PetscCheck(Mreuse, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Submatrix passed in was not used before, cannot reuse");
3809:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_REUSE_MATRIX, allcolumns, &Mreuse));
3810:   } else {
3811:     PetscCall(MatCreateSubMatrices_MPIAIJ_SingleIS_Local(mat, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, allcolumns, &Mreuse));
3812:   }

3814:   /*
3815:       m - number of local rows
3816:       n - number of columns (same on all processors)
3817:       rstart - first row in new global matrix generated
3818:   */
3819:   PetscCall(MatGetSize(Mreuse, &m, &n));
3820:   PetscCall(MatGetBlockSizes(Mreuse, &bs, &cbs));
3821:   if (call == MAT_INITIAL_MATRIX) {
3822:     aij = (Mat_SeqAIJ *)Mreuse->data;
3823:     ii  = aij->i;
3824:     jj  = aij->j;

3826:     /*
3827:         Determine the number of non-zeros in the diagonal and off-diagonal
3828:         portions of the matrix in order to do correct preallocation
3829:     */

3831:     /* first get start and end of "diagonal" columns */
3832:     if (csize == PETSC_DECIDE) {
3833:       PetscCall(ISGetSize(isrow, &mglobal));
3834:       if (mglobal == n) { /* square matrix */
3835:         nlocal = m;
3836:       } else {
3837:         nlocal = n / size + ((n % size) > rank);
3838:       }
3839:     } else {
3840:       nlocal = csize;
3841:     }
3842:     PetscCallMPI(MPI_Scan(&nlocal, &rend, 1, MPIU_INT, MPI_SUM, comm));
3843:     rstart = rend - nlocal;
3844:     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);

3846:     /* next, compute all the lengths */
3847:     PetscCall(PetscMalloc1(2 * m + 1, &dlens));
3848:     olens = dlens + m;
3849:     for (i = 0; i < m; i++) {
3850:       jend = ii[i + 1] - ii[i];
3851:       olen = 0;
3852:       dlen = 0;
3853:       for (j = 0; j < jend; j++) {
3854:         if (*jj < rstart || *jj >= rend) olen++;
3855:         else dlen++;
3856:         jj++;
3857:       }
3858:       olens[i] = olen;
3859:       dlens[i] = dlen;
3860:     }
3861:     PetscCall(MatCreate(comm, &M));
3862:     PetscCall(MatSetSizes(M, m, nlocal, PETSC_DECIDE, n));
3863:     PetscCall(MatSetBlockSizes(M, bs, cbs));
3864:     PetscCall(MatSetType(M, ((PetscObject)mat)->type_name));
3865:     PetscCall(MatMPIAIJSetPreallocation(M, 0, dlens, 0, olens));
3866:     PetscCall(PetscFree(dlens));
3867:   } else {
3868:     PetscInt ml, nl;

3870:     M = *newmat;
3871:     PetscCall(MatGetLocalSize(M, &ml, &nl));
3872:     PetscCheck(ml == m, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Previous matrix must be same size/layout as request");
3873:     PetscCall(MatZeroEntries(M));
3874:     /*
3875:          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3876:        rather than the slower MatSetValues().
3877:     */
3878:     M->was_assembled = PETSC_TRUE;
3879:     M->assembled     = PETSC_FALSE;
3880:   }
3881:   PetscCall(MatGetOwnershipRange(M, &rstart, &rend));
3882:   aij = (Mat_SeqAIJ *)Mreuse->data;
3883:   ii  = aij->i;
3884:   jj  = aij->j;

3886:   /* trigger copy to CPU if needed */
3887:   PetscCall(MatSeqAIJGetArrayRead(Mreuse, (const PetscScalar **)&aa));
3888:   for (i = 0; i < m; i++) {
3889:     row   = rstart + i;
3890:     nz    = ii[i + 1] - ii[i];
3891:     cwork = jj;
3892:     jj    = PetscSafePointerPlusOffset(jj, nz);
3893:     vwork = aa;
3894:     aa    = PetscSafePointerPlusOffset(aa, nz);
3895:     PetscCall(MatSetValues_MPIAIJ(M, 1, &row, nz, cwork, vwork, INSERT_VALUES));
3896:   }
3897:   PetscCall(MatSeqAIJRestoreArrayRead(Mreuse, (const PetscScalar **)&aa));

3899:   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
3900:   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
3901:   *newmat = M;

3903:   /* save submatrix used in processor for next request */
3904:   if (call == MAT_INITIAL_MATRIX) {
3905:     PetscCall(PetscObjectCompose((PetscObject)M, "SubMatrix", (PetscObject)Mreuse));
3906:     PetscCall(MatDestroy(&Mreuse));
3907:   }
3908:   PetscFunctionReturn(PETSC_SUCCESS);
3909: }

3911: static PetscErrorCode MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
3912: {
3913:   PetscInt        m, cstart, cend, j, nnz, i, d, *ld;
3914:   PetscInt       *d_nnz, *o_nnz, nnz_max = 0, rstart, ii, irstart;
3915:   const PetscInt *JJ;
3916:   PetscBool       nooffprocentries;
3917:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)B->data;

3919:   PetscFunctionBegin;
3920:   PetscCall(PetscLayoutSetUp(B->rmap));
3921:   PetscCall(PetscLayoutSetUp(B->cmap));
3922:   m       = B->rmap->n;
3923:   cstart  = B->cmap->rstart;
3924:   cend    = B->cmap->rend;
3925:   rstart  = B->rmap->rstart;
3926:   irstart = Ii[0];

3928:   PetscCall(PetscCalloc2(m, &d_nnz, m, &o_nnz));

3930:   if (PetscDefined(USE_DEBUG)) {
3931:     for (i = 0; i < m; i++) {
3932:       nnz = Ii[i + 1] - Ii[i];
3933:       JJ  = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3934:       PetscCheck(nnz >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local row %" PetscInt_FMT " has a negative %" PetscInt_FMT " number of columns", i, nnz);
3935:       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]);
3936:       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);
3937:     }
3938:   }

3940:   for (i = 0; i < m; i++) {
3941:     nnz     = Ii[i + 1] - Ii[i];
3942:     JJ      = PetscSafePointerPlusOffset(J, Ii[i] - irstart);
3943:     nnz_max = PetscMax(nnz_max, nnz);
3944:     d       = 0;
3945:     for (j = 0; j < nnz; j++) {
3946:       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3947:     }
3948:     d_nnz[i] = d;
3949:     o_nnz[i] = nnz - d;
3950:   }
3951:   PetscCall(MatMPIAIJSetPreallocation(B, 0, d_nnz, 0, o_nnz));
3952:   PetscCall(PetscFree2(d_nnz, o_nnz));

3954:   for (i = 0; i < m; i++) {
3955:     ii = i + rstart;
3956:     PetscCall(MatSetValues_MPIAIJ(B, 1, &ii, Ii[i + 1] - Ii[i], PetscSafePointerPlusOffset(J, Ii[i] - irstart), PetscSafePointerPlusOffset(v, Ii[i] - irstart), INSERT_VALUES));
3957:   }
3958:   nooffprocentries    = B->nooffprocentries;
3959:   B->nooffprocentries = PETSC_TRUE;
3960:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
3961:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
3962:   B->nooffprocentries = nooffprocentries;

3964:   /* count number of entries below block diagonal */
3965:   PetscCall(PetscFree(Aij->ld));
3966:   PetscCall(PetscCalloc1(m, &ld));
3967:   Aij->ld = ld;
3968:   for (i = 0; i < m; i++) {
3969:     nnz = Ii[i + 1] - Ii[i];
3970:     j   = 0;
3971:     while (j < nnz && J[j] < cstart) j++;
3972:     ld[i] = j;
3973:     if (J) J += nnz;
3974:   }

3976:   PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
3977:   PetscFunctionReturn(PETSC_SUCCESS);
3978: }

3980: /*@
3981:   MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in `MATAIJ` format
3982:   (the default parallel PETSc format).

3984:   Collective

3986:   Input Parameters:
3987: + B - the matrix
3988: . i - the indices into `j` for the start of each local row (indices start with zero)
3989: . j - the column indices for each local row (indices start with zero)
3990: - v - optional values in the matrix

3992:   Level: developer

3994:   Notes:
3995:   The `i`, `j`, and `v` arrays ARE copied by this routine into the internal format used by PETSc;
3996:   thus you CANNOT change the matrix entries by changing the values of `v` after you have
3997:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

3999:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4001:   A convenience routine for this functionality is `MatCreateMPIAIJWithArrays()`.

4003:   You can update the matrix with new numerical values using `MatUpdateMPIAIJWithArrays()` after this call if the column indices in `j` are sorted.

4005:   If you do **not** use `MatUpdateMPIAIJWithArrays()`, the column indices in `j` do not need to be sorted. If you will use
4006:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4008:   The format which is used for the sparse matrix input, is equivalent to a
4009:   row-major ordering.. i.e for the following matrix, the input data expected is
4010:   as shown
4011: .vb
4012:         1 0 0
4013:         2 0 3     P0
4014:        -------
4015:         4 5 6     P1

4017:      Process0 [P0] rows_owned=[0,1]
4018:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4019:         j =  {0,0,2}  [size = 3]
4020:         v =  {1,2,3}  [size = 3]

4022:      Process1 [P1] rows_owned=[2]
4023:         i =  {0,3}    [size = nrow+1  = 1+1]
4024:         j =  {0,1,2}  [size = 3]
4025:         v =  {4,5,6}  [size = 3]
4026: .ve

4028: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatCreateAIJ()`,
4029:           `MatCreateSeqAIJWithArrays()`, `MatCreateMPIAIJWithSplitArrays()`, `MatCreateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4030: @*/
4031: PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
4032: {
4033:   PetscFunctionBegin;
4034:   PetscTryMethod(B, "MatMPIAIJSetPreallocationCSR_C", (Mat, const PetscInt[], const PetscInt[], const PetscScalar[]), (B, i, j, v));
4035:   PetscFunctionReturn(PETSC_SUCCESS);
4036: }

4038: /*@
4039:   MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in `MATMPIAIJ` format
4040:   (the default parallel PETSc format).  For good matrix assembly performance
4041:   the user should preallocate the matrix storage by setting the parameters
4042:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4044:   Collective

4046:   Input Parameters:
4047: + B     - the matrix
4048: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4049:            (same value is used for all local rows)
4050: . d_nnz - array containing the number of nonzeros in the various rows of the
4051:            DIAGONAL portion of the local submatrix (possibly different for each row)
4052:            or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `d_nz` is used to specify the nonzero structure.
4053:            The size of this array is equal to the number of local rows, i.e 'm'.
4054:            For matrices that will be factored, you must leave room for (and set)
4055:            the diagonal entry even if it is zero.
4056: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4057:            submatrix (same value is used for all local rows).
4058: - o_nnz - array containing the number of nonzeros in the various rows of the
4059:            OFF-DIAGONAL portion of the local submatrix (possibly different for
4060:            each row) or `NULL` (`PETSC_NULL_INTEGER` in Fortran), if `o_nz` is used to specify the nonzero
4061:            structure. The size of this array is equal to the number
4062:            of local rows, i.e 'm'.

4064:   Example Usage:
4065:   Consider the following 8x8 matrix with 34 non-zero values, that is
4066:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4067:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4068:   as follows

4070: .vb
4071:             1  2  0  |  0  3  0  |  0  4
4072:     Proc0   0  5  6  |  7  0  0  |  8  0
4073:             9  0 10  | 11  0  0  | 12  0
4074:     -------------------------------------
4075:            13  0 14  | 15 16 17  |  0  0
4076:     Proc1   0 18  0  | 19 20 21  |  0  0
4077:             0  0  0  | 22 23  0  | 24  0
4078:     -------------------------------------
4079:     Proc2  25 26 27  |  0  0 28  | 29  0
4080:            30  0  0  | 31 32 33  |  0 34
4081: .ve

4083:   This can be represented as a collection of submatrices as
4084: .vb
4085:       A B C
4086:       D E F
4087:       G H I
4088: .ve

4090:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4091:   owned by proc1, G,H,I are owned by proc2.

4093:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4094:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4095:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4097:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4098:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4099:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4100:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4101:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4102:   matrix, ans [DF] as another `MATSEQAIJ` matrix.

4104:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4105:   allocated for every row of the local diagonal submatrix, and `o_nz`
4106:   storage locations are allocated for every row of the OFF-DIAGONAL submat.
4107:   One way to choose `d_nz` and `o_nz` is to use the max nonzerors per local
4108:   rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4109:   In this case, the values of `d_nz`, `o_nz` are
4110: .vb
4111:      proc0  dnz = 2, o_nz = 2
4112:      proc1  dnz = 3, o_nz = 2
4113:      proc2  dnz = 1, o_nz = 4
4114: .ve
4115:   We are allocating `m`*(`d_nz`+`o_nz`) storage locations for every proc. This
4116:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4117:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4118:   34 values.

4120:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4121:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4122:   In the above case the values for `d_nnz`, `o_nnz` are
4123: .vb
4124:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4125:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4126:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4127: .ve
4128:   Here the space allocated is sum of all the above values i.e 34, and
4129:   hence pre-allocation is perfect.

4131:   Level: intermediate

4133:   Notes:
4134:   If the *_nnz parameter is given then the *_nz parameter is ignored

4136:   The `MATAIJ` format, also called compressed row storage (CSR), is compatible with standard Fortran
4137:   storage.  The stored row and column indices begin with zero.
4138:   See [Sparse Matrices](sec_matsparse) for details.

4140:   The parallel matrix is partitioned such that the first m0 rows belong to
4141:   process 0, the next m1 rows belong to process 1, the next m2 rows belong
4142:   to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.

4144:   The DIAGONAL portion of the local submatrix of a processor can be defined
4145:   as the submatrix which is obtained by extraction the part corresponding to
4146:   the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4147:   first row that belongs to the processor, r2 is the last row belonging to
4148:   the this processor, and c1-c2 is range of indices of the local part of a
4149:   vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4150:   common case of a square matrix, the row and column ranges are the same and
4151:   the DIAGONAL part is also square. The remaining portion of the local
4152:   submatrix (mxN) constitute the OFF-DIAGONAL portion.

4154:   If `o_nnz` and `d_nnz` are specified, then `o_nz` and `d_nz` are ignored.

4156:   You can call `MatGetInfo()` to get information on how effective the preallocation was;
4157:   for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4158:   You can also run with the option `-info` and look for messages with the string
4159:   malloc in them to see if additional memory allocation was needed.

4161: .seealso: [](ch_matrices), `Mat`, [Sparse Matrices](sec_matsparse), `MATMPIAIJ`, `MATAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatCreateAIJ()`, `MatMPIAIJSetPreallocationCSR()`,
4162:           `MatGetInfo()`, `PetscSplitOwnership()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4163: @*/
4164: PetscErrorCode MatMPIAIJSetPreallocation(Mat B, PetscInt d_nz, const PetscInt d_nnz[], PetscInt o_nz, const PetscInt o_nnz[])
4165: {
4166:   PetscFunctionBegin;
4169:   PetscTryMethod(B, "MatMPIAIJSetPreallocation_C", (Mat, PetscInt, const PetscInt[], PetscInt, const PetscInt[]), (B, d_nz, d_nnz, o_nz, o_nnz));
4170:   PetscFunctionReturn(PETSC_SUCCESS);
4171: }

4173: /*@
4174:   MatCreateMPIAIJWithArrays - creates a `MATMPIAIJ` matrix using arrays that contain in standard
4175:   CSR format for the local rows.

4177:   Collective

4179:   Input Parameters:
4180: + comm - MPI communicator
4181: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
4182: . n    - This value should be the same as the local size used in creating the
4183:          x vector for the matrix-vector product $ y = Ax$. (or `PETSC_DECIDE` to have
4184:          calculated if `N` is given) For square matrices n is almost always `m`.
4185: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
4186: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
4187: . 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
4188: . j    - global column indices
4189: - a    - optional matrix values

4191:   Output Parameter:
4192: . mat - the matrix

4194:   Level: intermediate

4196:   Notes:
4197:   The `i`, `j`, and `a` arrays ARE copied by this routine into the internal format used by PETSc;
4198:   thus you CANNOT change the matrix entries by changing the values of `a[]` after you have
4199:   called this routine. Use `MatCreateMPIAIJWithSplitArrays()` to avoid needing to copy the arrays.

4201:   The `i` and `j` indices are 0 based, and `i` indices are indices corresponding to the local `j` array.

4203:   Once you have created the matrix you can update it with new numerical values using `MatUpdateMPIAIJWithArray()`

4205:   If you do **not** use `MatUpdateMPIAIJWithArray()`, the column indices in `j` do not need to be sorted. If you will use
4206:   `MatUpdateMPIAIJWithArrays()`, the column indices **must** be sorted.

4208:   The format which is used for the sparse matrix input, is equivalent to a
4209:   row-major ordering, i.e., for the following matrix, the input data expected is
4210:   as shown
4211: .vb
4212:         1 0 0
4213:         2 0 3     P0
4214:        -------
4215:         4 5 6     P1

4217:      Process0 [P0] rows_owned=[0,1]
4218:         i =  {0,1,3}  [size = nrow+1  = 2+1]
4219:         j =  {0,0,2}  [size = 3]
4220:         v =  {1,2,3}  [size = 3]

4222:      Process1 [P1] rows_owned=[2]
4223:         i =  {0,3}    [size = nrow+1  = 1+1]
4224:         j =  {0,1,2}  [size = 3]
4225:         v =  {4,5,6}  [size = 3]
4226: .ve

4228: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4229:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4230: @*/
4231: PetscErrorCode MatCreateMPIAIJWithArrays(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt i[], const PetscInt j[], const PetscScalar a[], Mat *mat)
4232: {
4233:   PetscFunctionBegin;
4234:   PetscCheck(!i || !i[0], PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4235:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4236:   PetscCall(MatCreate(comm, mat));
4237:   PetscCall(MatSetSizes(*mat, m, n, M, N));
4238:   /* PetscCall(MatSetBlockSizes(M,bs,cbs)); */
4239:   PetscCall(MatSetType(*mat, MATMPIAIJ));
4240:   PetscCall(MatMPIAIJSetPreallocationCSR(*mat, i, j, a));
4241:   PetscFunctionReturn(PETSC_SUCCESS);
4242: }

4244: /*@
4245:   MatUpdateMPIAIJWithArrays - updates a `MATMPIAIJ` matrix using arrays that contain in standard
4246:   CSR format for the local rows. Only the numerical values are updated the other arrays must be identical to what was passed
4247:   from `MatCreateMPIAIJWithArrays()`

4249:   Deprecated: Use `MatUpdateMPIAIJWithArray()`

4251:   Collective

4253:   Input Parameters:
4254: + mat - the matrix
4255: . m   - number of local rows (Cannot be `PETSC_DECIDE`)
4256: . n   - This value should be the same as the local size used in creating the
4257:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4258:        calculated if N is given) For square matrices n is almost always m.
4259: . M   - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4260: . N   - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4261: . Ii  - row indices; that is Ii[0] = 0, Ii[row] = Ii[row-1] + number of elements in that row of the matrix
4262: . J   - column indices
4263: - v   - matrix values

4265:   Level: deprecated

4267: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4268:           `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArray()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4269: @*/
4270: PetscErrorCode MatUpdateMPIAIJWithArrays(Mat mat, PetscInt m, PetscInt n, PetscInt M, PetscInt N, const PetscInt Ii[], const PetscInt J[], const PetscScalar v[])
4271: {
4272:   PetscInt        nnz, i;
4273:   PetscBool       nooffprocentries;
4274:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4275:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4276:   PetscScalar    *ad, *ao;
4277:   PetscInt        ldi, Iii, md;
4278:   const PetscInt *Adi = Ad->i;
4279:   PetscInt       *ld  = Aij->ld;

4281:   PetscFunctionBegin;
4282:   PetscCheck(Ii[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
4283:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
4284:   PetscCheck(m == mat->rmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of rows cannot change from call to MatUpdateMPIAIJWithArrays()");
4285:   PetscCheck(n == mat->cmap->n, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Local number of columns cannot change from call to MatUpdateMPIAIJWithArrays()");

4287:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4288:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));

4290:   for (i = 0; i < m; i++) {
4291:     if (PetscDefined(USE_DEBUG)) {
4292:       for (PetscInt j = Ii[i] + 1; j < Ii[i + 1]; ++j) {
4293:         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);
4294:         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);
4295:       }
4296:     }
4297:     nnz = Ii[i + 1] - Ii[i];
4298:     Iii = Ii[i];
4299:     ldi = ld[i];
4300:     md  = Adi[i + 1] - Adi[i];
4301:     PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4302:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4303:     PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4304:     ad += md;
4305:     ao += nnz - md;
4306:   }
4307:   nooffprocentries      = mat->nooffprocentries;
4308:   mat->nooffprocentries = PETSC_TRUE;
4309:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4310:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4311:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4312:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4313:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4314:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4315:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4316:   mat->nooffprocentries = nooffprocentries;
4317:   PetscFunctionReturn(PETSC_SUCCESS);
4318: }

4320: /*@
4321:   MatUpdateMPIAIJWithArray - updates an `MATMPIAIJ` matrix using an array that contains the nonzero values

4323:   Collective

4325:   Input Parameters:
4326: + mat - the matrix
4327: - v   - matrix values, stored by row

4329:   Level: intermediate

4331:   Notes:
4332:   The matrix must have been obtained with `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()`

4334:   The column indices in the call to `MatCreateMPIAIJWithArrays()` or `MatMPIAIJSetPreallocationCSR()` must have been sorted for this call to work correctly

4336: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4337:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithSplitArrays()`, `MatUpdateMPIAIJWithArrays()`, `MatSetPreallocationCOO()`, `MatSetValuesCOO()`
4338: @*/
4339: PetscErrorCode MatUpdateMPIAIJWithArray(Mat mat, const PetscScalar v[])
4340: {
4341:   PetscInt        nnz, i, m;
4342:   PetscBool       nooffprocentries;
4343:   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ *)mat->data;
4344:   Mat_SeqAIJ     *Ad  = (Mat_SeqAIJ *)Aij->A->data;
4345:   Mat_SeqAIJ     *Ao  = (Mat_SeqAIJ *)Aij->B->data;
4346:   PetscScalar    *ad, *ao;
4347:   const PetscInt *Adi = Ad->i, *Adj = Ao->i;
4348:   PetscInt        ldi, Iii, md;
4349:   PetscInt       *ld = Aij->ld;

4351:   PetscFunctionBegin;
4352:   m = mat->rmap->n;

4354:   PetscCall(MatSeqAIJGetArrayWrite(Aij->A, &ad));
4355:   PetscCall(MatSeqAIJGetArrayWrite(Aij->B, &ao));
4356:   Iii = 0;
4357:   for (i = 0; i < m; i++) {
4358:     nnz = Adi[i + 1] - Adi[i] + Adj[i + 1] - Adj[i];
4359:     ldi = ld[i];
4360:     md  = Adi[i + 1] - Adi[i];
4361:     PetscCall(PetscArraycpy(ad, v + Iii + ldi, md));
4362:     ad += md;
4363:     if (ao) {
4364:       PetscCall(PetscArraycpy(ao, v + Iii, ldi));
4365:       PetscCall(PetscArraycpy(ao + ldi, v + Iii + ldi + md, nnz - ldi - md));
4366:       ao += nnz - md;
4367:     }
4368:     Iii += nnz;
4369:   }
4370:   nooffprocentries      = mat->nooffprocentries;
4371:   mat->nooffprocentries = PETSC_TRUE;
4372:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->A, &ad));
4373:   PetscCall(MatSeqAIJRestoreArrayWrite(Aij->B, &ao));
4374:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->A));
4375:   PetscCall(PetscObjectStateIncrease((PetscObject)Aij->B));
4376:   PetscCall(PetscObjectStateIncrease((PetscObject)mat));
4377:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
4378:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
4379:   mat->nooffprocentries = nooffprocentries;
4380:   PetscFunctionReturn(PETSC_SUCCESS);
4381: }

4383: /*@
4384:   MatCreateAIJ - Creates a sparse parallel matrix in `MATAIJ` format
4385:   (the default parallel PETSc format).  For good matrix assembly performance
4386:   the user should preallocate the matrix storage by setting the parameters
4387:   `d_nz` (or `d_nnz`) and `o_nz` (or `o_nnz`).

4389:   Collective

4391:   Input Parameters:
4392: + comm  - MPI communicator
4393: . m     - number of local rows (or `PETSC_DECIDE` to have calculated if M is given)
4394:           This value should be the same as the local size used in creating the
4395:           y vector for the matrix-vector product y = Ax.
4396: . n     - This value should be the same as the local size used in creating the
4397:           x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
4398:           calculated if N is given) For square matrices n is almost always m.
4399: . M     - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
4400: . N     - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
4401: . d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4402:           (same value is used for all local rows)
4403: . d_nnz - array containing the number of nonzeros in the various rows of the
4404:           DIAGONAL portion of the local submatrix (possibly different for each row)
4405:           or `NULL`, if `d_nz` is used to specify the nonzero structure.
4406:           The size of this array is equal to the number of local rows, i.e 'm'.
4407: . o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4408:           submatrix (same value is used for all local rows).
4409: - o_nnz - array containing the number of nonzeros in the various rows of the
4410:           OFF-DIAGONAL portion of the local submatrix (possibly different for
4411:           each row) or `NULL`, if `o_nz` is used to specify the nonzero
4412:           structure. The size of this array is equal to the number
4413:           of local rows, i.e 'm'.

4415:   Output Parameter:
4416: . A - the matrix

4418:   Options Database Keys:
4419: + -mat_no_inode                     - Do not use inodes
4420: . -mat_inode_limit <limit>          - Sets inode limit (max limit=5)
4421: - -matmult_vecscatter_view <viewer> - View the vecscatter (i.e., communication pattern) used in `MatMult()` of sparse parallel matrices.
4422:                                       See viewer types in manual of `MatView()`. Of them, ascii_matlab, draw or binary cause the `VecScatter`
4423:                                       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.

4425:   Level: intermediate

4427:   Notes:
4428:   It is recommended that one use `MatCreateFromOptions()` or the `MatCreate()`, `MatSetType()` and/or `MatSetFromOptions()`,
4429:   MatXXXXSetPreallocation() paradigm instead of this routine directly.
4430:   [MatXXXXSetPreallocation() is, for example, `MatSeqAIJSetPreallocation()`]

4432:   If the *_nnz parameter is given then the *_nz parameter is ignored

4434:   The `m`,`n`,`M`,`N` parameters specify the size of the matrix, and its partitioning across
4435:   processors, while `d_nz`,`d_nnz`,`o_nz`,`o_nnz` parameters specify the approximate
4436:   storage requirements for this matrix.

4438:   If `PETSC_DECIDE` or  `PETSC_DETERMINE` is used for a particular argument on one
4439:   processor than it must be used on all processors that share the object for
4440:   that argument.

4442:   If `m` and `n` are not `PETSC_DECIDE`, then the values determine the `PetscLayout` of the matrix and the ranges returned by
4443:   `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`, and `MatGetOwnershipRangesColumn()`.

4445:   The user MUST specify either the local or global matrix dimensions
4446:   (possibly both).

4448:   The parallel matrix is partitioned across processors such that the
4449:   first `m0` rows belong to process 0, the next `m1` rows belong to
4450:   process 1, the next `m2` rows belong to process 2, etc., where
4451:   `m0`, `m1`, `m2`... are the input parameter `m` on each MPI process. I.e., each MPI process stores
4452:   values corresponding to [m x N] submatrix.

4454:   The columns are logically partitioned with the n0 columns belonging
4455:   to 0th partition, the next n1 columns belonging to the next
4456:   partition etc.. where n0,n1,n2... are the input parameter 'n'.

4458:   The DIAGONAL portion of the local submatrix on any given processor
4459:   is the submatrix corresponding to the rows and columns m,n
4460:   corresponding to the given processor. i.e diagonal matrix on
4461:   process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4462:   etc. The remaining portion of the local submatrix [m x (N-n)]
4463:   constitute the OFF-DIAGONAL portion. The example below better
4464:   illustrates this concept.

4466:   For a square global matrix we define each processor's diagonal portion
4467:   to be its local rows and the corresponding columns (a square submatrix);
4468:   each processor's off-diagonal portion encompasses the remainder of the
4469:   local matrix (a rectangular submatrix).

4471:   If `o_nnz`, `d_nnz` are specified, then `o_nz`, and `d_nz` are ignored.

4473:   When calling this routine with a single process communicator, a matrix of
4474:   type `MATSEQAIJ` is returned.  If a matrix of type `MATMPIAIJ` is desired for this
4475:   type of communicator, use the construction mechanism
4476: .vb
4477:   MatCreate(..., &A);
4478:   MatSetType(A, MATMPIAIJ);
4479:   MatSetSizes(A, m, n, M, N);
4480:   MatMPIAIJSetPreallocation(A, ...);
4481: .ve

4483:   By default, this format uses inodes (identical nodes) when possible.
4484:   We search for consecutive rows with the same nonzero structure, thereby
4485:   reusing matrix information to achieve increased efficiency.

4487:   Example Usage:
4488:   Consider the following 8x8 matrix with 34 non-zero values, that is
4489:   assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4490:   proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4491:   as follows

4493: .vb
4494:             1  2  0  |  0  3  0  |  0  4
4495:     Proc0   0  5  6  |  7  0  0  |  8  0
4496:             9  0 10  | 11  0  0  | 12  0
4497:     -------------------------------------
4498:            13  0 14  | 15 16 17  |  0  0
4499:     Proc1   0 18  0  | 19 20 21  |  0  0
4500:             0  0  0  | 22 23  0  | 24  0
4501:     -------------------------------------
4502:     Proc2  25 26 27  |  0  0 28  | 29  0
4503:            30  0  0  | 31 32 33  |  0 34
4504: .ve

4506:   This can be represented as a collection of submatrices as

4508: .vb
4509:       A B C
4510:       D E F
4511:       G H I
4512: .ve

4514:   Where the submatrices A,B,C are owned by proc0, D,E,F are
4515:   owned by proc1, G,H,I are owned by proc2.

4517:   The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4518:   The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4519:   The 'M','N' parameters are 8,8, and have the same values on all procs.

4521:   The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4522:   submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4523:   corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4524:   Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4525:   part as `MATSEQAIJ` matrices. For example, proc1 will store [E] as a `MATSEQAIJ`
4526:   matrix, ans [DF] as another SeqAIJ matrix.

4528:   When `d_nz`, `o_nz` parameters are specified, `d_nz` storage elements are
4529:   allocated for every row of the local diagonal submatrix, and `o_nz`
4530:   storage locations are allocated for every row of the OFF-DIAGONAL submat.
4531:   One way to choose `d_nz` and `o_nz` is to use the max nonzerors per local
4532:   rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4533:   In this case, the values of `d_nz`,`o_nz` are
4534: .vb
4535:      proc0  dnz = 2, o_nz = 2
4536:      proc1  dnz = 3, o_nz = 2
4537:      proc2  dnz = 1, o_nz = 4
4538: .ve
4539:   We are allocating m*(`d_nz`+`o_nz`) storage locations for every proc. This
4540:   translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4541:   for proc3. i.e we are using 12+15+10=37 storage locations to store
4542:   34 values.

4544:   When `d_nnz`, `o_nnz` parameters are specified, the storage is specified
4545:   for every row, corresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4546:   In the above case the values for d_nnz,o_nnz are
4547: .vb
4548:      proc0 d_nnz = [2,2,2] and o_nnz = [2,2,2]
4549:      proc1 d_nnz = [3,3,2] and o_nnz = [2,1,1]
4550:      proc2 d_nnz = [1,1]   and o_nnz = [4,4]
4551: .ve
4552:   Here the space allocated is sum of all the above values i.e 34, and
4553:   hence pre-allocation is perfect.

4555: .seealso: [](ch_matrices), `Mat`, [Sparse Matrix Creation](sec_matsparse), `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
4556:           `MATMPIAIJ`, `MatCreateMPIAIJWithArrays()`, `MatGetOwnershipRange()`, `MatGetOwnershipRanges()`, `MatGetOwnershipRangeColumn()`,
4557:           `MatGetOwnershipRangesColumn()`, `PetscLayout`
4558: @*/
4559: 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)
4560: {
4561:   PetscMPIInt size;

4563:   PetscFunctionBegin;
4564:   PetscCall(MatCreate(comm, A));
4565:   PetscCall(MatSetSizes(*A, m, n, M, N));
4566:   PetscCallMPI(MPI_Comm_size(comm, &size));
4567:   if (size > 1) {
4568:     PetscCall(MatSetType(*A, MATMPIAIJ));
4569:     PetscCall(MatMPIAIJSetPreallocation(*A, d_nz, d_nnz, o_nz, o_nnz));
4570:   } else {
4571:     PetscCall(MatSetType(*A, MATSEQAIJ));
4572:     PetscCall(MatSeqAIJSetPreallocation(*A, d_nz, d_nnz));
4573:   }
4574:   PetscFunctionReturn(PETSC_SUCCESS);
4575: }

4577: /*MC
4578:     MatMPIAIJGetSeqAIJF90 - Returns the local pieces of this distributed matrix

4580:     Synopsis:
4581:     MatMPIAIJGetSeqAIJF90(Mat A, Mat Ad, Mat Ao, {PetscInt, pointer :: colmap(:)},integer ierr)

4583:     Not Collective

4585:     Input Parameter:
4586: .   A - the `MATMPIAIJ` matrix

4588:     Output Parameters:
4589: +   Ad - the diagonal portion of the matrix
4590: .   Ao - the off-diagonal portion of the matrix
4591: .   colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix
4592: -   ierr - error code

4594:      Level: advanced

4596:     Note:
4597:     Use  `MatMPIAIJRestoreSeqAIJF90()` when you no longer need access to the matrices and `colmap`

4599: .seealso: [](ch_matrices), `Mat`, [](sec_fortranarrays), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJ()`, `MatMPIAIJRestoreSeqAIJF90()`
4600: M*/

4602: /*MC
4603:     MatMPIAIJRestoreSeqAIJF90 - call after `MatMPIAIJGetSeqAIJF90()` when you no longer need access to the matrices and `colmap`

4605:     Synopsis:
4606:     MatMPIAIJRestoreSeqAIJF90(Mat A, Mat Ad, Mat Ao, {PetscInt, pointer :: colmap(:)},integer ierr)

4608:     Not Collective

4610:     Input Parameters:
4611: +   A - the `MATMPIAIJ` matrix
4612: .   Ad - the diagonal portion of the matrix
4613: .   Ao - the off-diagonal portion of the matrix
4614: .   colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix
4615: -   ierr - error code

4617:      Level: advanced

4619: .seealso: [](ch_matrices), `Mat`, [](sec_fortranarrays), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJ()`, `MatMPIAIJGetSeqAIJF90()`
4620: M*/

4622: /*@C
4623:   MatMPIAIJGetSeqAIJ - Returns the local pieces of this distributed matrix

4625:   Not Collective

4627:   Input Parameter:
4628: . A - The `MATMPIAIJ` matrix

4630:   Output Parameters:
4631: + Ad     - The local diagonal block as a `MATSEQAIJ` matrix
4632: . Ao     - The local off-diagonal block as a `MATSEQAIJ` matrix
4633: - colmap - An array mapping local column numbers of `Ao` to global column numbers of the parallel matrix

4635:   Level: intermediate

4637:   Note:
4638:   The rows in `Ad` and `Ao` are in [0, Nr), where Nr is the number of local rows on this process. The columns
4639:   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
4640:   the number of nonzero columns in the local off-diagonal piece of the matrix `A`. The array colmap maps these
4641:   local column numbers to global column numbers in the original matrix.

4643:   Fortran Notes:
4644:   `MatMPIAIJGetSeqAIJ()` Fortran binding is deprecated (since PETSc 3.19), use `MatMPIAIJGetSeqAIJF90()`

4646: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatMPIAIJGetSeqAIJF90()`, `MatMPIAIJRestoreSeqAIJF90()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`, `MatCreateAIJ()`, `MATSEQAIJ`
4647: @*/
4648: PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A, Mat *Ad, Mat *Ao, const PetscInt *colmap[])
4649: {
4650:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
4651:   PetscBool   flg;

4653:   PetscFunctionBegin;
4654:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &flg));
4655:   PetscCheck(flg, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "This function requires a MATMPIAIJ matrix as input");
4656:   if (Ad) *Ad = a->A;
4657:   if (Ao) *Ao = a->B;
4658:   if (colmap) *colmap = a->garray;
4659:   PetscFunctionReturn(PETSC_SUCCESS);
4660: }

4662: PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm, Mat inmat, PetscInt n, MatReuse scall, Mat *outmat)
4663: {
4664:   PetscInt     m, N, i, rstart, nnz, Ii;
4665:   PetscInt    *indx;
4666:   PetscScalar *values;
4667:   MatType      rootType;

4669:   PetscFunctionBegin;
4670:   PetscCall(MatGetSize(inmat, &m, &N));
4671:   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
4672:     PetscInt *dnz, *onz, sum, bs, cbs;

4674:     if (n == PETSC_DECIDE) PetscCall(PetscSplitOwnership(comm, &n, &N));
4675:     /* Check sum(n) = N */
4676:     PetscCallMPI(MPIU_Allreduce(&n, &sum, 1, MPIU_INT, MPI_SUM, comm));
4677:     PetscCheck(sum == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Sum of local columns %" PetscInt_FMT " != global columns %" PetscInt_FMT, sum, N);

4679:     PetscCallMPI(MPI_Scan(&m, &rstart, 1, MPIU_INT, MPI_SUM, comm));
4680:     rstart -= m;

4682:     MatPreallocateBegin(comm, m, n, dnz, onz);
4683:     for (i = 0; i < m; i++) {
4684:       PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4685:       PetscCall(MatPreallocateSet(i + rstart, nnz, indx, dnz, onz));
4686:       PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, NULL));
4687:     }

4689:     PetscCall(MatCreate(comm, outmat));
4690:     PetscCall(MatSetSizes(*outmat, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
4691:     PetscCall(MatGetBlockSizes(inmat, &bs, &cbs));
4692:     PetscCall(MatSetBlockSizes(*outmat, bs, cbs));
4693:     PetscCall(MatGetRootType_Private(inmat, &rootType));
4694:     PetscCall(MatSetType(*outmat, rootType));
4695:     PetscCall(MatSeqAIJSetPreallocation(*outmat, 0, dnz));
4696:     PetscCall(MatMPIAIJSetPreallocation(*outmat, 0, dnz, 0, onz));
4697:     MatPreallocateEnd(dnz, onz);
4698:     PetscCall(MatSetOption(*outmat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
4699:   }

4701:   /* numeric phase */
4702:   PetscCall(MatGetOwnershipRange(*outmat, &rstart, NULL));
4703:   for (i = 0; i < m; i++) {
4704:     PetscCall(MatGetRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4705:     Ii = i + rstart;
4706:     PetscCall(MatSetValues(*outmat, 1, &Ii, nnz, indx, values, INSERT_VALUES));
4707:     PetscCall(MatRestoreRow_SeqAIJ(inmat, i, &nnz, &indx, &values));
4708:   }
4709:   PetscCall(MatAssemblyBegin(*outmat, MAT_FINAL_ASSEMBLY));
4710:   PetscCall(MatAssemblyEnd(*outmat, MAT_FINAL_ASSEMBLY));
4711:   PetscFunctionReturn(PETSC_SUCCESS);
4712: }

4714: static PetscErrorCode MatDestroy_MPIAIJ_SeqsToMPI(void **data)
4715: {
4716:   Mat_Merge_SeqsToMPI *merge = (Mat_Merge_SeqsToMPI *)*data;

4718:   PetscFunctionBegin;
4719:   if (!merge) PetscFunctionReturn(PETSC_SUCCESS);
4720:   PetscCall(PetscFree(merge->id_r));
4721:   PetscCall(PetscFree(merge->len_s));
4722:   PetscCall(PetscFree(merge->len_r));
4723:   PetscCall(PetscFree(merge->bi));
4724:   PetscCall(PetscFree(merge->bj));
4725:   PetscCall(PetscFree(merge->buf_ri[0]));
4726:   PetscCall(PetscFree(merge->buf_ri));
4727:   PetscCall(PetscFree(merge->buf_rj[0]));
4728:   PetscCall(PetscFree(merge->buf_rj));
4729:   PetscCall(PetscFree(merge->coi));
4730:   PetscCall(PetscFree(merge->coj));
4731:   PetscCall(PetscFree(merge->owners_co));
4732:   PetscCall(PetscLayoutDestroy(&merge->rowmap));
4733:   PetscCall(PetscFree(merge));
4734:   PetscFunctionReturn(PETSC_SUCCESS);
4735: }

4737: #include <../src/mat/utils/freespace.h>
4738: #include <petscbt.h>

4740: PetscErrorCode MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat, Mat mpimat)
4741: {
4742:   MPI_Comm             comm;
4743:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4744:   PetscMPIInt          size, rank, taga, *len_s;
4745:   PetscInt             N = mpimat->cmap->N, i, j, *owners, *ai = a->i, *aj, m;
4746:   PetscMPIInt          proc, k;
4747:   PetscInt           **buf_ri, **buf_rj;
4748:   PetscInt             anzi, *bj_i, *bi, *bj, arow, bnzi, nextaj;
4749:   PetscInt             nrows, **buf_ri_k, **nextrow, **nextai;
4750:   MPI_Request         *s_waits, *r_waits;
4751:   MPI_Status          *status;
4752:   const MatScalar     *aa, *a_a;
4753:   MatScalar          **abuf_r, *ba_i;
4754:   Mat_Merge_SeqsToMPI *merge;
4755:   PetscContainer       container;

4757:   PetscFunctionBegin;
4758:   PetscCall(PetscObjectGetComm((PetscObject)mpimat, &comm));
4759:   PetscCall(PetscLogEventBegin(MAT_Seqstompinum, seqmat, 0, 0, 0));

4761:   PetscCallMPI(MPI_Comm_size(comm, &size));
4762:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4764:   PetscCall(PetscObjectQuery((PetscObject)mpimat, "MatMergeSeqsToMPI", (PetscObject *)&container));
4765:   PetscCheck(container, PetscObjectComm((PetscObject)mpimat), PETSC_ERR_PLIB, "Mat not created from MatCreateMPIAIJSumSeqAIJSymbolic");
4766:   PetscCall(PetscContainerGetPointer(container, (void **)&merge));
4767:   PetscCall(MatSeqAIJGetArrayRead(seqmat, &a_a));
4768:   aa = a_a;

4770:   bi     = merge->bi;
4771:   bj     = merge->bj;
4772:   buf_ri = merge->buf_ri;
4773:   buf_rj = merge->buf_rj;

4775:   PetscCall(PetscMalloc1(size, &status));
4776:   owners = merge->rowmap->range;
4777:   len_s  = merge->len_s;

4779:   /* send and recv matrix values */
4780:   PetscCall(PetscObjectGetNewTag((PetscObject)mpimat, &taga));
4781:   PetscCall(PetscPostIrecvScalar(comm, taga, merge->nrecv, merge->id_r, merge->len_r, &abuf_r, &r_waits));

4783:   PetscCall(PetscMalloc1(merge->nsend + 1, &s_waits));
4784:   for (proc = 0, k = 0; proc < size; proc++) {
4785:     if (!len_s[proc]) continue;
4786:     i = owners[proc];
4787:     PetscCallMPI(MPIU_Isend(aa + ai[i], len_s[proc], MPIU_MATSCALAR, proc, taga, comm, s_waits + k));
4788:     k++;
4789:   }

4791:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, r_waits, status));
4792:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, s_waits, status));
4793:   PetscCall(PetscFree(status));

4795:   PetscCall(PetscFree(s_waits));
4796:   PetscCall(PetscFree(r_waits));

4798:   /* insert mat values of mpimat */
4799:   PetscCall(PetscMalloc1(N, &ba_i));
4800:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

4802:   for (k = 0; k < merge->nrecv; k++) {
4803:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4804:     nrows       = *buf_ri_k[k];
4805:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
4806:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
4807:   }

4809:   /* set values of ba */
4810:   m = merge->rowmap->n;
4811:   for (i = 0; i < m; i++) {
4812:     arow = owners[rank] + i;
4813:     bj_i = bj + bi[i]; /* col indices of the i-th row of mpimat */
4814:     bnzi = bi[i + 1] - bi[i];
4815:     PetscCall(PetscArrayzero(ba_i, bnzi));

4817:     /* add local non-zero vals of this proc's seqmat into ba */
4818:     anzi   = ai[arow + 1] - ai[arow];
4819:     aj     = a->j + ai[arow];
4820:     aa     = a_a + ai[arow];
4821:     nextaj = 0;
4822:     for (j = 0; nextaj < anzi; j++) {
4823:       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4824:         ba_i[j] += aa[nextaj++];
4825:       }
4826:     }

4828:     /* add received vals into ba */
4829:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
4830:       /* i-th row */
4831:       if (i == *nextrow[k]) {
4832:         anzi   = *(nextai[k] + 1) - *nextai[k];
4833:         aj     = buf_rj[k] + *nextai[k];
4834:         aa     = abuf_r[k] + *nextai[k];
4835:         nextaj = 0;
4836:         for (j = 0; nextaj < anzi; j++) {
4837:           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4838:             ba_i[j] += aa[nextaj++];
4839:           }
4840:         }
4841:         nextrow[k]++;
4842:         nextai[k]++;
4843:       }
4844:     }
4845:     PetscCall(MatSetValues(mpimat, 1, &arow, bnzi, bj_i, ba_i, INSERT_VALUES));
4846:   }
4847:   PetscCall(MatSeqAIJRestoreArrayRead(seqmat, &a_a));
4848:   PetscCall(MatAssemblyBegin(mpimat, MAT_FINAL_ASSEMBLY));
4849:   PetscCall(MatAssemblyEnd(mpimat, MAT_FINAL_ASSEMBLY));

4851:   PetscCall(PetscFree(abuf_r[0]));
4852:   PetscCall(PetscFree(abuf_r));
4853:   PetscCall(PetscFree(ba_i));
4854:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));
4855:   PetscCall(PetscLogEventEnd(MAT_Seqstompinum, seqmat, 0, 0, 0));
4856:   PetscFunctionReturn(PETSC_SUCCESS);
4857: }

4859: PetscErrorCode MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, Mat *mpimat)
4860: {
4861:   Mat                  B_mpi;
4862:   Mat_SeqAIJ          *a = (Mat_SeqAIJ *)seqmat->data;
4863:   PetscMPIInt          size, rank, tagi, tagj, *len_s, *len_si, *len_ri;
4864:   PetscInt           **buf_rj, **buf_ri, **buf_ri_k;
4865:   PetscInt             M = seqmat->rmap->n, N = seqmat->cmap->n, i, *owners, *ai = a->i, *aj = a->j;
4866:   PetscInt             len, *dnz, *onz, bs, cbs;
4867:   PetscInt             k, anzi, *bi, *bj, *lnk, nlnk, arow, bnzi;
4868:   PetscInt             nrows, *buf_s, *buf_si, *buf_si_i, **nextrow, **nextai;
4869:   MPI_Request         *si_waits, *sj_waits, *ri_waits, *rj_waits;
4870:   MPI_Status          *status;
4871:   PetscFreeSpaceList   free_space = NULL, current_space = NULL;
4872:   PetscBT              lnkbt;
4873:   Mat_Merge_SeqsToMPI *merge;
4874:   PetscContainer       container;

4876:   PetscFunctionBegin;
4877:   PetscCall(PetscLogEventBegin(MAT_Seqstompisym, seqmat, 0, 0, 0));

4879:   /* make sure it is a PETSc comm */
4880:   PetscCall(PetscCommDuplicate(comm, &comm, NULL));
4881:   PetscCallMPI(MPI_Comm_size(comm, &size));
4882:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

4884:   PetscCall(PetscNew(&merge));
4885:   PetscCall(PetscMalloc1(size, &status));

4887:   /* determine row ownership */
4888:   PetscCall(PetscLayoutCreate(comm, &merge->rowmap));
4889:   PetscCall(PetscLayoutSetLocalSize(merge->rowmap, m));
4890:   PetscCall(PetscLayoutSetSize(merge->rowmap, M));
4891:   PetscCall(PetscLayoutSetBlockSize(merge->rowmap, 1));
4892:   PetscCall(PetscLayoutSetUp(merge->rowmap));
4893:   PetscCall(PetscMalloc1(size, &len_si));
4894:   PetscCall(PetscMalloc1(size, &merge->len_s));

4896:   m      = merge->rowmap->n;
4897:   owners = merge->rowmap->range;

4899:   /* determine the number of messages to send, their lengths */
4900:   len_s = merge->len_s;

4902:   len          = 0; /* length of buf_si[] */
4903:   merge->nsend = 0;
4904:   for (PetscMPIInt proc = 0; proc < size; proc++) {
4905:     len_si[proc] = 0;
4906:     if (proc == rank) {
4907:       len_s[proc] = 0;
4908:     } else {
4909:       PetscCall(PetscMPIIntCast(owners[proc + 1] - owners[proc] + 1, &len_si[proc]));
4910:       PetscCall(PetscMPIIntCast(ai[owners[proc + 1]] - ai[owners[proc]], &len_s[proc])); /* num of rows to be sent to [proc] */
4911:     }
4912:     if (len_s[proc]) {
4913:       merge->nsend++;
4914:       nrows = 0;
4915:       for (i = owners[proc]; i < owners[proc + 1]; i++) {
4916:         if (ai[i + 1] > ai[i]) nrows++;
4917:       }
4918:       PetscCall(PetscMPIIntCast(2 * (nrows + 1), &len_si[proc]));
4919:       len += len_si[proc];
4920:     }
4921:   }

4923:   /* determine the number and length of messages to receive for ij-structure */
4924:   PetscCall(PetscGatherNumberOfMessages(comm, NULL, len_s, &merge->nrecv));
4925:   PetscCall(PetscGatherMessageLengths2(comm, merge->nsend, merge->nrecv, len_s, len_si, &merge->id_r, &merge->len_r, &len_ri));

4927:   /* post the Irecv of j-structure */
4928:   PetscCall(PetscCommGetNewTag(comm, &tagj));
4929:   PetscCall(PetscPostIrecvInt(comm, tagj, merge->nrecv, merge->id_r, merge->len_r, &buf_rj, &rj_waits));

4931:   /* post the Isend of j-structure */
4932:   PetscCall(PetscMalloc2(merge->nsend, &si_waits, merge->nsend, &sj_waits));

4934:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4935:     if (!len_s[proc]) continue;
4936:     i = owners[proc];
4937:     PetscCallMPI(MPIU_Isend(aj + ai[i], len_s[proc], MPIU_INT, proc, tagj, comm, sj_waits + k));
4938:     k++;
4939:   }

4941:   /* receives and sends of j-structure are complete */
4942:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, rj_waits, status));
4943:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, sj_waits, status));

4945:   /* send and recv i-structure */
4946:   PetscCall(PetscCommGetNewTag(comm, &tagi));
4947:   PetscCall(PetscPostIrecvInt(comm, tagi, merge->nrecv, merge->id_r, len_ri, &buf_ri, &ri_waits));

4949:   PetscCall(PetscMalloc1(len + 1, &buf_s));
4950:   buf_si = buf_s; /* points to the beginning of k-th msg to be sent */
4951:   for (PetscMPIInt proc = 0, k = 0; proc < size; proc++) {
4952:     if (!len_s[proc]) continue;
4953:     /* form outgoing message for i-structure:
4954:          buf_si[0]:                 nrows to be sent
4955:                [1:nrows]:           row index (global)
4956:                [nrows+1:2*nrows+1]: i-structure index
4957:     */
4958:     nrows       = len_si[proc] / 2 - 1;
4959:     buf_si_i    = buf_si + nrows + 1;
4960:     buf_si[0]   = nrows;
4961:     buf_si_i[0] = 0;
4962:     nrows       = 0;
4963:     for (i = owners[proc]; i < owners[proc + 1]; i++) {
4964:       anzi = ai[i + 1] - ai[i];
4965:       if (anzi) {
4966:         buf_si_i[nrows + 1] = buf_si_i[nrows] + anzi; /* i-structure */
4967:         buf_si[nrows + 1]   = i - owners[proc];       /* local row index */
4968:         nrows++;
4969:       }
4970:     }
4971:     PetscCallMPI(MPIU_Isend(buf_si, len_si[proc], MPIU_INT, proc, tagi, comm, si_waits + k));
4972:     k++;
4973:     buf_si += len_si[proc];
4974:   }

4976:   if (merge->nrecv) PetscCallMPI(MPI_Waitall(merge->nrecv, ri_waits, status));
4977:   if (merge->nsend) PetscCallMPI(MPI_Waitall(merge->nsend, si_waits, status));

4979:   PetscCall(PetscInfo(seqmat, "nsend: %d, nrecv: %d\n", merge->nsend, merge->nrecv));
4980:   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]));

4982:   PetscCall(PetscFree(len_si));
4983:   PetscCall(PetscFree(len_ri));
4984:   PetscCall(PetscFree(rj_waits));
4985:   PetscCall(PetscFree2(si_waits, sj_waits));
4986:   PetscCall(PetscFree(ri_waits));
4987:   PetscCall(PetscFree(buf_s));
4988:   PetscCall(PetscFree(status));

4990:   /* compute a local seq matrix in each processor */
4991:   /* allocate bi array and free space for accumulating nonzero column info */
4992:   PetscCall(PetscMalloc1(m + 1, &bi));
4993:   bi[0] = 0;

4995:   /* create and initialize a linked list */
4996:   nlnk = N + 1;
4997:   PetscCall(PetscLLCreate(N, N, nlnk, lnk, lnkbt));

4999:   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
5000:   len = ai[owners[rank + 1]] - ai[owners[rank]];
5001:   PetscCall(PetscFreeSpaceGet(PetscIntMultTruncate(2, len) + 1, &free_space));

5003:   current_space = free_space;

5005:   /* determine symbolic info for each local row */
5006:   PetscCall(PetscMalloc3(merge->nrecv, &buf_ri_k, merge->nrecv, &nextrow, merge->nrecv, &nextai));

5008:   for (k = 0; k < merge->nrecv; k++) {
5009:     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
5010:     nrows       = *buf_ri_k[k];
5011:     nextrow[k]  = buf_ri_k[k] + 1;           /* next row number of k-th recved i-structure */
5012:     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* points to the next i-structure of k-th recved i-structure  */
5013:   }

5015:   MatPreallocateBegin(comm, m, n, dnz, onz);
5016:   len = 0;
5017:   for (i = 0; i < m; i++) {
5018:     bnzi = 0;
5019:     /* add local non-zero cols of this proc's seqmat into lnk */
5020:     arow = owners[rank] + i;
5021:     anzi = ai[arow + 1] - ai[arow];
5022:     aj   = a->j + ai[arow];
5023:     PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
5024:     bnzi += nlnk;
5025:     /* add received col data into lnk */
5026:     for (k = 0; k < merge->nrecv; k++) { /* k-th received message */
5027:       if (i == *nextrow[k]) {            /* i-th row */
5028:         anzi = *(nextai[k] + 1) - *nextai[k];
5029:         aj   = buf_rj[k] + *nextai[k];
5030:         PetscCall(PetscLLAddSorted(anzi, aj, N, &nlnk, lnk, lnkbt));
5031:         bnzi += nlnk;
5032:         nextrow[k]++;
5033:         nextai[k]++;
5034:       }
5035:     }
5036:     if (len < bnzi) len = bnzi; /* =max(bnzi) */

5038:     /* if free space is not available, make more free space */
5039:     if (current_space->local_remaining < bnzi) PetscCall(PetscFreeSpaceGet(PetscIntSumTruncate(bnzi, current_space->total_array_size), &current_space));
5040:     /* copy data into free space, then initialize lnk */
5041:     PetscCall(PetscLLClean(N, N, bnzi, lnk, current_space->array, lnkbt));
5042:     PetscCall(MatPreallocateSet(i + owners[rank], bnzi, current_space->array, dnz, onz));

5044:     current_space->array += bnzi;
5045:     current_space->local_used += bnzi;
5046:     current_space->local_remaining -= bnzi;

5048:     bi[i + 1] = bi[i] + bnzi;
5049:   }

5051:   PetscCall(PetscFree3(buf_ri_k, nextrow, nextai));

5053:   PetscCall(PetscMalloc1(bi[m] + 1, &bj));
5054:   PetscCall(PetscFreeSpaceContiguous(&free_space, bj));
5055:   PetscCall(PetscLLDestroy(lnk, lnkbt));

5057:   /* create symbolic parallel matrix B_mpi */
5058:   PetscCall(MatGetBlockSizes(seqmat, &bs, &cbs));
5059:   PetscCall(MatCreate(comm, &B_mpi));
5060:   if (n == PETSC_DECIDE) {
5061:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, N));
5062:   } else {
5063:     PetscCall(MatSetSizes(B_mpi, m, n, PETSC_DETERMINE, PETSC_DETERMINE));
5064:   }
5065:   PetscCall(MatSetBlockSizes(B_mpi, bs, cbs));
5066:   PetscCall(MatSetType(B_mpi, MATMPIAIJ));
5067:   PetscCall(MatMPIAIJSetPreallocation(B_mpi, 0, dnz, 0, onz));
5068:   MatPreallocateEnd(dnz, onz);
5069:   PetscCall(MatSetOption(B_mpi, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));

5071:   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5072:   B_mpi->assembled = PETSC_FALSE;
5073:   merge->bi        = bi;
5074:   merge->bj        = bj;
5075:   merge->buf_ri    = buf_ri;
5076:   merge->buf_rj    = buf_rj;
5077:   merge->coi       = NULL;
5078:   merge->coj       = NULL;
5079:   merge->owners_co = NULL;

5081:   PetscCall(PetscCommDestroy(&comm));

5083:   /* attach the supporting struct to B_mpi for reuse */
5084:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
5085:   PetscCall(PetscContainerSetPointer(container, merge));
5086:   PetscCall(PetscContainerSetCtxDestroy(container, MatDestroy_MPIAIJ_SeqsToMPI));
5087:   PetscCall(PetscObjectCompose((PetscObject)B_mpi, "MatMergeSeqsToMPI", (PetscObject)container));
5088:   PetscCall(PetscContainerDestroy(&container));
5089:   *mpimat = B_mpi;

5091:   PetscCall(PetscLogEventEnd(MAT_Seqstompisym, seqmat, 0, 0, 0));
5092:   PetscFunctionReturn(PETSC_SUCCESS);
5093: }

5095: /*@
5096:   MatCreateMPIAIJSumSeqAIJ - Creates a `MATMPIAIJ` matrix by adding sequential
5097:   matrices from each processor

5099:   Collective

5101:   Input Parameters:
5102: + comm   - the communicators the parallel matrix will live on
5103: . seqmat - the input sequential matrices
5104: . m      - number of local rows (or `PETSC_DECIDE`)
5105: . n      - number of local columns (or `PETSC_DECIDE`)
5106: - scall  - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5108:   Output Parameter:
5109: . mpimat - the parallel matrix generated

5111:   Level: advanced

5113:   Note:
5114:   The dimensions of the sequential matrix in each processor MUST be the same.
5115:   The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
5116:   destroyed when `mpimat` is destroyed. Call `PetscObjectQuery()` to access `seqmat`.

5118: .seealso: [](ch_matrices), `Mat`, `MatCreateAIJ()`
5119: @*/
5120: PetscErrorCode MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm, Mat seqmat, PetscInt m, PetscInt n, MatReuse scall, Mat *mpimat)
5121: {
5122:   PetscMPIInt size;

5124:   PetscFunctionBegin;
5125:   PetscCallMPI(MPI_Comm_size(comm, &size));
5126:   if (size == 1) {
5127:     PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5128:     if (scall == MAT_INITIAL_MATRIX) {
5129:       PetscCall(MatDuplicate(seqmat, MAT_COPY_VALUES, mpimat));
5130:     } else {
5131:       PetscCall(MatCopy(seqmat, *mpimat, SAME_NONZERO_PATTERN));
5132:     }
5133:     PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5134:     PetscFunctionReturn(PETSC_SUCCESS);
5135:   }
5136:   PetscCall(PetscLogEventBegin(MAT_Seqstompi, seqmat, 0, 0, 0));
5137:   if (scall == MAT_INITIAL_MATRIX) PetscCall(MatCreateMPIAIJSumSeqAIJSymbolic(comm, seqmat, m, n, mpimat));
5138:   PetscCall(MatCreateMPIAIJSumSeqAIJNumeric(seqmat, *mpimat));
5139:   PetscCall(PetscLogEventEnd(MAT_Seqstompi, seqmat, 0, 0, 0));
5140:   PetscFunctionReturn(PETSC_SUCCESS);
5141: }

5143: /*@
5144:   MatAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATAIJ` matrix.

5146:   Not Collective

5148:   Input Parameter:
5149: . A - the matrix

5151:   Output Parameter:
5152: . A_loc - the local sequential matrix generated

5154:   Level: developer

5156:   Notes:
5157:   The matrix is created by taking `A`'s local rows and putting them into a sequential matrix
5158:   with `mlocal` rows and `n` columns. Where `mlocal` is obtained with `MatGetLocalSize()` and
5159:   `n` is the global column count obtained with `MatGetSize()`

5161:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5163:   For parallel matrices this creates an entirely new matrix. If the matrix is sequential it merely increases the reference count.

5165:   Destroy the matrix with `MatDestroy()`

5167: .seealso: [](ch_matrices), `Mat`, `MatMPIAIJGetLocalMat()`
5168: @*/
5169: PetscErrorCode MatAIJGetLocalMat(Mat A, Mat *A_loc)
5170: {
5171:   PetscBool mpi;

5173:   PetscFunctionBegin;
5174:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &mpi));
5175:   if (mpi) {
5176:     PetscCall(MatMPIAIJGetLocalMat(A, MAT_INITIAL_MATRIX, A_loc));
5177:   } else {
5178:     *A_loc = A;
5179:     PetscCall(PetscObjectReference((PetscObject)*A_loc));
5180:   }
5181:   PetscFunctionReturn(PETSC_SUCCESS);
5182: }

5184: /*@
5185:   MatMPIAIJGetLocalMat - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix.

5187:   Not Collective

5189:   Input Parameters:
5190: + A     - the matrix
5191: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5193:   Output Parameter:
5194: . A_loc - the local sequential matrix generated

5196:   Level: developer

5198:   Notes:
5199:   The matrix is created by taking all `A`'s local rows and putting them into a sequential
5200:   matrix with `mlocal` rows and `n` columns.`mlocal` is the row count obtained with
5201:   `MatGetLocalSize()` and `n` is the global column count obtained with `MatGetSize()`.

5203:   In other words combines the two parts of a parallel `MATMPIAIJ` matrix on each process to a single matrix.

5205:   When `A` is sequential and `MAT_INITIAL_MATRIX` is requested, the matrix returned is the diagonal part of `A` (which contains the entire matrix),
5206:   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
5207:   then `MatCopy`(Adiag,*`A_loc`,`SAME_NONZERO_PATTERN`) is called to fill `A_loc`. Thus one can preallocate the appropriate sequential matrix `A_loc`
5208:   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.

5210: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMatCondensed()`, `MatMPIAIJGetLocalMatMerge()`
5211: @*/
5212: PetscErrorCode MatMPIAIJGetLocalMat(Mat A, MatReuse scall, Mat *A_loc)
5213: {
5214:   Mat_MPIAIJ        *mpimat = (Mat_MPIAIJ *)A->data;
5215:   Mat_SeqAIJ        *mat, *a, *b;
5216:   PetscInt          *ai, *aj, *bi, *bj, *cmap = mpimat->garray;
5217:   const PetscScalar *aa, *ba, *aav, *bav;
5218:   PetscScalar       *ca, *cam;
5219:   PetscMPIInt        size;
5220:   PetscInt           am = A->rmap->n, i, j, k, cstart = A->cmap->rstart;
5221:   PetscInt          *ci, *cj, col, ncols_d, ncols_o, jo;
5222:   PetscBool          match;

5224:   PetscFunctionBegin;
5225:   PetscCall(PetscStrbeginswith(((PetscObject)A)->type_name, MATMPIAIJ, &match));
5226:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5227:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5228:   if (size == 1) {
5229:     if (scall == MAT_INITIAL_MATRIX) {
5230:       PetscCall(PetscObjectReference((PetscObject)mpimat->A));
5231:       *A_loc = mpimat->A;
5232:     } else if (scall == MAT_REUSE_MATRIX) {
5233:       PetscCall(MatCopy(mpimat->A, *A_loc, SAME_NONZERO_PATTERN));
5234:     }
5235:     PetscFunctionReturn(PETSC_SUCCESS);
5236:   }

5238:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5239:   a  = (Mat_SeqAIJ *)mpimat->A->data;
5240:   b  = (Mat_SeqAIJ *)mpimat->B->data;
5241:   ai = a->i;
5242:   aj = a->j;
5243:   bi = b->i;
5244:   bj = b->j;
5245:   PetscCall(MatSeqAIJGetArrayRead(mpimat->A, &aav));
5246:   PetscCall(MatSeqAIJGetArrayRead(mpimat->B, &bav));
5247:   aa = aav;
5248:   ba = bav;
5249:   if (scall == MAT_INITIAL_MATRIX) {
5250:     PetscCall(PetscMalloc1(1 + am, &ci));
5251:     ci[0] = 0;
5252:     for (i = 0; i < am; i++) ci[i + 1] = ci[i] + (ai[i + 1] - ai[i]) + (bi[i + 1] - bi[i]);
5253:     PetscCall(PetscMalloc1(1 + ci[am], &cj));
5254:     PetscCall(PetscMalloc1(1 + ci[am], &ca));
5255:     k = 0;
5256:     for (i = 0; i < am; i++) {
5257:       ncols_o = bi[i + 1] - bi[i];
5258:       ncols_d = ai[i + 1] - ai[i];
5259:       /* off-diagonal portion of A */
5260:       for (jo = 0; jo < ncols_o; jo++) {
5261:         col = cmap[*bj];
5262:         if (col >= cstart) break;
5263:         cj[k] = col;
5264:         bj++;
5265:         ca[k++] = *ba++;
5266:       }
5267:       /* diagonal portion of A */
5268:       for (j = 0; j < ncols_d; j++) {
5269:         cj[k]   = cstart + *aj++;
5270:         ca[k++] = *aa++;
5271:       }
5272:       /* off-diagonal portion of A */
5273:       for (j = jo; j < ncols_o; j++) {
5274:         cj[k]   = cmap[*bj++];
5275:         ca[k++] = *ba++;
5276:       }
5277:     }
5278:     /* put together the new matrix */
5279:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, A->cmap->N, ci, cj, ca, A_loc));
5280:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5281:     /* Since these are PETSc arrays, change flags to free them as necessary. */
5282:     mat          = (Mat_SeqAIJ *)(*A_loc)->data;
5283:     mat->free_a  = PETSC_TRUE;
5284:     mat->free_ij = PETSC_TRUE;
5285:     mat->nonew   = 0;
5286:   } else if (scall == MAT_REUSE_MATRIX) {
5287:     mat = (Mat_SeqAIJ *)(*A_loc)->data;
5288:     ci  = mat->i;
5289:     cj  = mat->j;
5290:     PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &cam));
5291:     for (i = 0; i < am; i++) {
5292:       /* off-diagonal portion of A */
5293:       ncols_o = bi[i + 1] - bi[i];
5294:       for (jo = 0; jo < ncols_o; jo++) {
5295:         col = cmap[*bj];
5296:         if (col >= cstart) break;
5297:         *cam++ = *ba++;
5298:         bj++;
5299:       }
5300:       /* diagonal portion of A */
5301:       ncols_d = ai[i + 1] - ai[i];
5302:       for (j = 0; j < ncols_d; j++) *cam++ = *aa++;
5303:       /* off-diagonal portion of A */
5304:       for (j = jo; j < ncols_o; j++) {
5305:         *cam++ = *ba++;
5306:         bj++;
5307:       }
5308:     }
5309:     PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &cam));
5310:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5311:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->A, &aav));
5312:   PetscCall(MatSeqAIJRestoreArrayRead(mpimat->B, &bav));
5313:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5314:   PetscFunctionReturn(PETSC_SUCCESS);
5315: }

5317: /*@
5318:   MatMPIAIJGetLocalMatMerge - Creates a `MATSEQAIJ` from a `MATMPIAIJ` matrix by taking all its local rows and putting them into a sequential matrix with
5319:   mlocal rows and n columns. Where n is the sum of the number of columns of the diagonal and off-diagonal part

5321:   Not Collective

5323:   Input Parameters:
5324: + A     - the matrix
5325: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5327:   Output Parameters:
5328: + glob  - sequential `IS` with global indices associated with the columns of the local sequential matrix generated (can be `NULL`)
5329: - A_loc - the local sequential matrix generated

5331:   Level: developer

5333:   Note:
5334:   This is different from `MatMPIAIJGetLocalMat()` since the first columns in the returning matrix are those associated with the diagonal
5335:   part, then those associated with the off-diagonal part (in its local ordering)

5337: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`, `MatMPIAIJGetLocalMatCondensed()`
5338: @*/
5339: PetscErrorCode MatMPIAIJGetLocalMatMerge(Mat A, MatReuse scall, IS *glob, Mat *A_loc)
5340: {
5341:   Mat             Ao, Ad;
5342:   const PetscInt *cmap;
5343:   PetscMPIInt     size;
5344:   PetscErrorCode (*f)(Mat, MatReuse, IS *, Mat *);

5346:   PetscFunctionBegin;
5347:   PetscCall(MatMPIAIJGetSeqAIJ(A, &Ad, &Ao, &cmap));
5348:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)A), &size));
5349:   if (size == 1) {
5350:     if (scall == MAT_INITIAL_MATRIX) {
5351:       PetscCall(PetscObjectReference((PetscObject)Ad));
5352:       *A_loc = Ad;
5353:     } else if (scall == MAT_REUSE_MATRIX) {
5354:       PetscCall(MatCopy(Ad, *A_loc, SAME_NONZERO_PATTERN));
5355:     }
5356:     if (glob) PetscCall(ISCreateStride(PetscObjectComm((PetscObject)Ad), Ad->cmap->n, Ad->cmap->rstart, 1, glob));
5357:     PetscFunctionReturn(PETSC_SUCCESS);
5358:   }
5359:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatMPIAIJGetLocalMatMerge_C", &f));
5360:   PetscCall(PetscLogEventBegin(MAT_Getlocalmat, A, 0, 0, 0));
5361:   if (f) {
5362:     PetscCall((*f)(A, scall, glob, A_loc));
5363:   } else {
5364:     Mat_SeqAIJ        *a = (Mat_SeqAIJ *)Ad->data;
5365:     Mat_SeqAIJ        *b = (Mat_SeqAIJ *)Ao->data;
5366:     Mat_SeqAIJ        *c;
5367:     PetscInt          *ai = a->i, *aj = a->j;
5368:     PetscInt          *bi = b->i, *bj = b->j;
5369:     PetscInt          *ci, *cj;
5370:     const PetscScalar *aa, *ba;
5371:     PetscScalar       *ca;
5372:     PetscInt           i, j, am, dn, on;

5374:     PetscCall(MatGetLocalSize(Ad, &am, &dn));
5375:     PetscCall(MatGetLocalSize(Ao, NULL, &on));
5376:     PetscCall(MatSeqAIJGetArrayRead(Ad, &aa));
5377:     PetscCall(MatSeqAIJGetArrayRead(Ao, &ba));
5378:     if (scall == MAT_INITIAL_MATRIX) {
5379:       PetscInt k;
5380:       PetscCall(PetscMalloc1(1 + am, &ci));
5381:       PetscCall(PetscMalloc1(ai[am] + bi[am], &cj));
5382:       PetscCall(PetscMalloc1(ai[am] + bi[am], &ca));
5383:       ci[0] = 0;
5384:       for (i = 0, k = 0; i < am; i++) {
5385:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5386:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5387:         ci[i + 1]              = ci[i] + ncols_o + ncols_d;
5388:         /* diagonal portion of A */
5389:         for (j = 0; j < ncols_d; j++, k++) {
5390:           cj[k] = *aj++;
5391:           ca[k] = *aa++;
5392:         }
5393:         /* off-diagonal portion of A */
5394:         for (j = 0; j < ncols_o; j++, k++) {
5395:           cj[k] = dn + *bj++;
5396:           ca[k] = *ba++;
5397:         }
5398:       }
5399:       /* put together the new matrix */
5400:       PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, am, dn + on, ci, cj, ca, A_loc));
5401:       /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5402:       /* Since these are PETSc arrays, change flags to free them as necessary. */
5403:       c          = (Mat_SeqAIJ *)(*A_loc)->data;
5404:       c->free_a  = PETSC_TRUE;
5405:       c->free_ij = PETSC_TRUE;
5406:       c->nonew   = 0;
5407:       PetscCall(MatSetType(*A_loc, ((PetscObject)Ad)->type_name));
5408:     } else if (scall == MAT_REUSE_MATRIX) {
5409:       PetscCall(MatSeqAIJGetArrayWrite(*A_loc, &ca));
5410:       for (i = 0; i < am; i++) {
5411:         const PetscInt ncols_d = ai[i + 1] - ai[i];
5412:         const PetscInt ncols_o = bi[i + 1] - bi[i];
5413:         /* diagonal portion of A */
5414:         for (j = 0; j < ncols_d; j++) *ca++ = *aa++;
5415:         /* off-diagonal portion of A */
5416:         for (j = 0; j < ncols_o; j++) *ca++ = *ba++;
5417:       }
5418:       PetscCall(MatSeqAIJRestoreArrayWrite(*A_loc, &ca));
5419:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid MatReuse %d", (int)scall);
5420:     PetscCall(MatSeqAIJRestoreArrayRead(Ad, &aa));
5421:     PetscCall(MatSeqAIJRestoreArrayRead(Ao, &aa));
5422:     if (glob) {
5423:       PetscInt cst, *gidx;

5425:       PetscCall(MatGetOwnershipRangeColumn(A, &cst, NULL));
5426:       PetscCall(PetscMalloc1(dn + on, &gidx));
5427:       for (i = 0; i < dn; i++) gidx[i] = cst + i;
5428:       for (i = 0; i < on; i++) gidx[i + dn] = cmap[i];
5429:       PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)Ad), dn + on, gidx, PETSC_OWN_POINTER, glob));
5430:     }
5431:   }
5432:   PetscCall(PetscLogEventEnd(MAT_Getlocalmat, A, 0, 0, 0));
5433:   PetscFunctionReturn(PETSC_SUCCESS);
5434: }

5436: /*@C
5437:   MatMPIAIJGetLocalMatCondensed - Creates a `MATSEQAIJ` matrix from an `MATMPIAIJ` matrix by taking all its local rows and NON-ZERO columns

5439:   Not Collective

5441:   Input Parameters:
5442: + A     - the matrix
5443: . scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`
5444: . row   - index set of rows to extract (or `NULL`)
5445: - col   - index set of columns to extract (or `NULL`)

5447:   Output Parameter:
5448: . A_loc - the local sequential matrix generated

5450:   Level: developer

5452: .seealso: [](ch_matrices), `Mat`, `MATMPIAIJ`, `MatGetOwnershipRange()`, `MatMPIAIJGetLocalMat()`
5453: @*/
5454: PetscErrorCode MatMPIAIJGetLocalMatCondensed(Mat A, MatReuse scall, IS *row, IS *col, Mat *A_loc)
5455: {
5456:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5457:   PetscInt    i, start, end, ncols, nzA, nzB, *cmap, imark, *idx;
5458:   IS          isrowa, iscola;
5459:   Mat        *aloc;
5460:   PetscBool   match;

5462:   PetscFunctionBegin;
5463:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATMPIAIJ, &match));
5464:   PetscCheck(match, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Requires MATMPIAIJ matrix as input");
5465:   PetscCall(PetscLogEventBegin(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5466:   if (!row) {
5467:     start = A->rmap->rstart;
5468:     end   = A->rmap->rend;
5469:     PetscCall(ISCreateStride(PETSC_COMM_SELF, end - start, start, 1, &isrowa));
5470:   } else {
5471:     isrowa = *row;
5472:   }
5473:   if (!col) {
5474:     start = A->cmap->rstart;
5475:     cmap  = a->garray;
5476:     nzA   = a->A->cmap->n;
5477:     nzB   = a->B->cmap->n;
5478:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5479:     ncols = 0;
5480:     for (i = 0; i < nzB; i++) {
5481:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5482:       else break;
5483:     }
5484:     imark = i;
5485:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;
5486:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i];
5487:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &iscola));
5488:   } else {
5489:     iscola = *col;
5490:   }
5491:   if (scall != MAT_INITIAL_MATRIX) {
5492:     PetscCall(PetscMalloc1(1, &aloc));
5493:     aloc[0] = *A_loc;
5494:   }
5495:   PetscCall(MatCreateSubMatrices(A, 1, &isrowa, &iscola, scall, &aloc));
5496:   if (!col) { /* attach global id of condensed columns */
5497:     PetscCall(PetscObjectCompose((PetscObject)aloc[0], "_petsc_GetLocalMatCondensed_iscol", (PetscObject)iscola));
5498:   }
5499:   *A_loc = aloc[0];
5500:   PetscCall(PetscFree(aloc));
5501:   if (!row) PetscCall(ISDestroy(&isrowa));
5502:   if (!col) PetscCall(ISDestroy(&iscola));
5503:   PetscCall(PetscLogEventEnd(MAT_Getlocalmatcondensed, A, 0, 0, 0));
5504:   PetscFunctionReturn(PETSC_SUCCESS);
5505: }

5507: /*
5508:  * Create a sequential AIJ matrix based on row indices. a whole column is extracted once a row is matched.
5509:  * Row could be local or remote.The routine is designed to be scalable in memory so that nothing is based
5510:  * on a global size.
5511:  * */
5512: static PetscErrorCode MatCreateSeqSubMatrixWithRows_Private(Mat P, IS rows, Mat *P_oth)
5513: {
5514:   Mat_MPIAIJ            *p  = (Mat_MPIAIJ *)P->data;
5515:   Mat_SeqAIJ            *pd = (Mat_SeqAIJ *)p->A->data, *po = (Mat_SeqAIJ *)p->B->data, *p_oth;
5516:   PetscInt               plocalsize, nrows, *ilocal, *oilocal, i, lidx, *nrcols, *nlcols, ncol;
5517:   PetscMPIInt            owner;
5518:   PetscSFNode           *iremote, *oiremote;
5519:   const PetscInt        *lrowindices;
5520:   PetscSF                sf, osf;
5521:   PetscInt               pcstart, *roffsets, *loffsets, *pnnz, j;
5522:   PetscInt               ontotalcols, dntotalcols, ntotalcols, nout;
5523:   MPI_Comm               comm;
5524:   ISLocalToGlobalMapping mapping;
5525:   const PetscScalar     *pd_a, *po_a;

5527:   PetscFunctionBegin;
5528:   PetscCall(PetscObjectGetComm((PetscObject)P, &comm));
5529:   /* plocalsize is the number of roots
5530:    * nrows is the number of leaves
5531:    * */
5532:   PetscCall(MatGetLocalSize(P, &plocalsize, NULL));
5533:   PetscCall(ISGetLocalSize(rows, &nrows));
5534:   PetscCall(PetscCalloc1(nrows, &iremote));
5535:   PetscCall(ISGetIndices(rows, &lrowindices));
5536:   for (i = 0; i < nrows; i++) {
5537:     /* Find a remote index and an owner for a row
5538:      * The row could be local or remote
5539:      * */
5540:     owner = 0;
5541:     lidx  = 0;
5542:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, &lidx));
5543:     iremote[i].index = lidx;
5544:     iremote[i].rank  = owner;
5545:   }
5546:   /* Create SF to communicate how many nonzero columns for each row */
5547:   PetscCall(PetscSFCreate(comm, &sf));
5548:   /* SF will figure out the number of nonzero columns for each row, and their
5549:    * offsets
5550:    * */
5551:   PetscCall(PetscSFSetGraph(sf, plocalsize, nrows, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5552:   PetscCall(PetscSFSetFromOptions(sf));
5553:   PetscCall(PetscSFSetUp(sf));

5555:   PetscCall(PetscCalloc1(2 * (plocalsize + 1), &roffsets));
5556:   PetscCall(PetscCalloc1(2 * plocalsize, &nrcols));
5557:   PetscCall(PetscCalloc1(nrows, &pnnz));
5558:   roffsets[0] = 0;
5559:   roffsets[1] = 0;
5560:   for (i = 0; i < plocalsize; i++) {
5561:     /* diagonal */
5562:     nrcols[i * 2 + 0] = pd->i[i + 1] - pd->i[i];
5563:     /* off-diagonal */
5564:     nrcols[i * 2 + 1] = po->i[i + 1] - po->i[i];
5565:     /* compute offsets so that we relative location for each row */
5566:     roffsets[(i + 1) * 2 + 0] = roffsets[i * 2 + 0] + nrcols[i * 2 + 0];
5567:     roffsets[(i + 1) * 2 + 1] = roffsets[i * 2 + 1] + nrcols[i * 2 + 1];
5568:   }
5569:   PetscCall(PetscCalloc1(2 * nrows, &nlcols));
5570:   PetscCall(PetscCalloc1(2 * nrows, &loffsets));
5571:   /* 'r' means root, and 'l' means leaf */
5572:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5573:   PetscCall(PetscSFBcastBegin(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5574:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, nrcols, nlcols, MPI_REPLACE));
5575:   PetscCall(PetscSFBcastEnd(sf, MPIU_2INT, roffsets, loffsets, MPI_REPLACE));
5576:   PetscCall(PetscSFDestroy(&sf));
5577:   PetscCall(PetscFree(roffsets));
5578:   PetscCall(PetscFree(nrcols));
5579:   dntotalcols = 0;
5580:   ontotalcols = 0;
5581:   ncol        = 0;
5582:   for (i = 0; i < nrows; i++) {
5583:     pnnz[i] = nlcols[i * 2 + 0] + nlcols[i * 2 + 1];
5584:     ncol    = PetscMax(pnnz[i], ncol);
5585:     /* diagonal */
5586:     dntotalcols += nlcols[i * 2 + 0];
5587:     /* off-diagonal */
5588:     ontotalcols += nlcols[i * 2 + 1];
5589:   }
5590:   /* We do not need to figure the right number of columns
5591:    * since all the calculations will be done by going through the raw data
5592:    * */
5593:   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nrows, ncol, 0, pnnz, P_oth));
5594:   PetscCall(MatSetUp(*P_oth));
5595:   PetscCall(PetscFree(pnnz));
5596:   p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5597:   /* diagonal */
5598:   PetscCall(PetscCalloc1(dntotalcols, &iremote));
5599:   /* off-diagonal */
5600:   PetscCall(PetscCalloc1(ontotalcols, &oiremote));
5601:   /* diagonal */
5602:   PetscCall(PetscCalloc1(dntotalcols, &ilocal));
5603:   /* off-diagonal */
5604:   PetscCall(PetscCalloc1(ontotalcols, &oilocal));
5605:   dntotalcols = 0;
5606:   ontotalcols = 0;
5607:   ntotalcols  = 0;
5608:   for (i = 0; i < nrows; i++) {
5609:     owner = 0;
5610:     PetscCall(PetscLayoutFindOwnerIndex(P->rmap, lrowindices[i], &owner, NULL));
5611:     /* Set iremote for diag matrix */
5612:     for (j = 0; j < nlcols[i * 2 + 0]; j++) {
5613:       iremote[dntotalcols].index = loffsets[i * 2 + 0] + j;
5614:       iremote[dntotalcols].rank  = owner;
5615:       /* P_oth is seqAIJ so that ilocal need to point to the first part of memory */
5616:       ilocal[dntotalcols++] = ntotalcols++;
5617:     }
5618:     /* off-diagonal */
5619:     for (j = 0; j < nlcols[i * 2 + 1]; j++) {
5620:       oiremote[ontotalcols].index = loffsets[i * 2 + 1] + j;
5621:       oiremote[ontotalcols].rank  = owner;
5622:       oilocal[ontotalcols++]      = ntotalcols++;
5623:     }
5624:   }
5625:   PetscCall(ISRestoreIndices(rows, &lrowindices));
5626:   PetscCall(PetscFree(loffsets));
5627:   PetscCall(PetscFree(nlcols));
5628:   PetscCall(PetscSFCreate(comm, &sf));
5629:   /* P serves as roots and P_oth is leaves
5630:    * Diag matrix
5631:    * */
5632:   PetscCall(PetscSFSetGraph(sf, pd->i[plocalsize], dntotalcols, ilocal, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
5633:   PetscCall(PetscSFSetFromOptions(sf));
5634:   PetscCall(PetscSFSetUp(sf));

5636:   PetscCall(PetscSFCreate(comm, &osf));
5637:   /* off-diagonal */
5638:   PetscCall(PetscSFSetGraph(osf, po->i[plocalsize], ontotalcols, oilocal, PETSC_OWN_POINTER, oiremote, PETSC_OWN_POINTER));
5639:   PetscCall(PetscSFSetFromOptions(osf));
5640:   PetscCall(PetscSFSetUp(osf));
5641:   PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5642:   PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5643:   /* operate on the matrix internal data to save memory */
5644:   PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5645:   PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5646:   PetscCall(MatGetOwnershipRangeColumn(P, &pcstart, NULL));
5647:   /* Convert to global indices for diag matrix */
5648:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] += pcstart;
5649:   PetscCall(PetscSFBcastBegin(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5650:   /* We want P_oth store global indices */
5651:   PetscCall(ISLocalToGlobalMappingCreate(comm, 1, p->B->cmap->n, p->garray, PETSC_COPY_VALUES, &mapping));
5652:   /* Use memory scalable approach */
5653:   PetscCall(ISLocalToGlobalMappingSetType(mapping, ISLOCALTOGLOBALMAPPINGHASH));
5654:   PetscCall(ISLocalToGlobalMappingApply(mapping, po->i[plocalsize], po->j, po->j));
5655:   PetscCall(PetscSFBcastBegin(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5656:   PetscCall(PetscSFBcastEnd(sf, MPIU_INT, pd->j, p_oth->j, MPI_REPLACE));
5657:   /* Convert back to local indices */
5658:   for (i = 0; i < pd->i[plocalsize]; i++) pd->j[i] -= pcstart;
5659:   PetscCall(PetscSFBcastEnd(osf, MPIU_INT, po->j, p_oth->j, MPI_REPLACE));
5660:   nout = 0;
5661:   PetscCall(ISGlobalToLocalMappingApply(mapping, IS_GTOLM_DROP, po->i[plocalsize], po->j, &nout, po->j));
5662:   PetscCheck(nout == po->i[plocalsize], comm, PETSC_ERR_ARG_INCOMP, "n %" PetscInt_FMT " does not equal to nout %" PetscInt_FMT " ", po->i[plocalsize], nout);
5663:   PetscCall(ISLocalToGlobalMappingDestroy(&mapping));
5664:   /* Exchange values */
5665:   PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5666:   PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5667:   PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5668:   PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5669:   /* Stop PETSc from shrinking memory */
5670:   for (i = 0; i < nrows; i++) p_oth->ilen[i] = p_oth->imax[i];
5671:   PetscCall(MatAssemblyBegin(*P_oth, MAT_FINAL_ASSEMBLY));
5672:   PetscCall(MatAssemblyEnd(*P_oth, MAT_FINAL_ASSEMBLY));
5673:   /* Attach PetscSF objects to P_oth so that we can reuse it later */
5674:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "diagsf", (PetscObject)sf));
5675:   PetscCall(PetscObjectCompose((PetscObject)*P_oth, "offdiagsf", (PetscObject)osf));
5676:   PetscCall(PetscSFDestroy(&sf));
5677:   PetscCall(PetscSFDestroy(&osf));
5678:   PetscFunctionReturn(PETSC_SUCCESS);
5679: }

5681: /*
5682:  * Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5683:  * This supports MPIAIJ and MAIJ
5684:  * */
5685: PetscErrorCode MatGetBrowsOfAcols_MPIXAIJ(Mat A, Mat P, PetscInt dof, MatReuse reuse, Mat *P_oth)
5686: {
5687:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data, *p = (Mat_MPIAIJ *)P->data;
5688:   Mat_SeqAIJ *p_oth;
5689:   IS          rows, map;
5690:   PetscHMapI  hamp;
5691:   PetscInt    i, htsize, *rowindices, off, *mapping, key, count;
5692:   MPI_Comm    comm;
5693:   PetscSF     sf, osf;
5694:   PetscBool   has;

5696:   PetscFunctionBegin;
5697:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5698:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, P, 0, 0));
5699:   /* If it is the first time, create an index set of off-diag nonzero columns of A,
5700:    *  and then create a submatrix (that often is an overlapping matrix)
5701:    * */
5702:   if (reuse == MAT_INITIAL_MATRIX) {
5703:     /* Use a hash table to figure out unique keys */
5704:     PetscCall(PetscHMapICreateWithSize(a->B->cmap->n, &hamp));
5705:     PetscCall(PetscCalloc1(a->B->cmap->n, &mapping));
5706:     count = 0;
5707:     /* Assume that  a->g is sorted, otherwise the following does not make sense */
5708:     for (i = 0; i < a->B->cmap->n; i++) {
5709:       key = a->garray[i] / dof;
5710:       PetscCall(PetscHMapIHas(hamp, key, &has));
5711:       if (!has) {
5712:         mapping[i] = count;
5713:         PetscCall(PetscHMapISet(hamp, key, count++));
5714:       } else {
5715:         /* Current 'i' has the same value the previous step */
5716:         mapping[i] = count - 1;
5717:       }
5718:     }
5719:     PetscCall(ISCreateGeneral(comm, a->B->cmap->n, mapping, PETSC_OWN_POINTER, &map));
5720:     PetscCall(PetscHMapIGetSize(hamp, &htsize));
5721:     PetscCheck(htsize == count, comm, PETSC_ERR_ARG_INCOMP, " Size of hash map %" PetscInt_FMT " is inconsistent with count %" PetscInt_FMT, htsize, count);
5722:     PetscCall(PetscCalloc1(htsize, &rowindices));
5723:     off = 0;
5724:     PetscCall(PetscHMapIGetKeys(hamp, &off, rowindices));
5725:     PetscCall(PetscHMapIDestroy(&hamp));
5726:     PetscCall(PetscSortInt(htsize, rowindices));
5727:     PetscCall(ISCreateGeneral(comm, htsize, rowindices, PETSC_OWN_POINTER, &rows));
5728:     /* In case, the matrix was already created but users want to recreate the matrix */
5729:     PetscCall(MatDestroy(P_oth));
5730:     PetscCall(MatCreateSeqSubMatrixWithRows_Private(P, rows, P_oth));
5731:     PetscCall(PetscObjectCompose((PetscObject)*P_oth, "aoffdiagtopothmapping", (PetscObject)map));
5732:     PetscCall(ISDestroy(&map));
5733:     PetscCall(ISDestroy(&rows));
5734:   } else if (reuse == MAT_REUSE_MATRIX) {
5735:     /* If matrix was already created, we simply update values using SF objects
5736:      * that as attached to the matrix earlier.
5737:      */
5738:     const PetscScalar *pd_a, *po_a;

5740:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "diagsf", (PetscObject *)&sf));
5741:     PetscCall(PetscObjectQuery((PetscObject)*P_oth, "offdiagsf", (PetscObject *)&osf));
5742:     PetscCheck(sf && osf, comm, PETSC_ERR_ARG_NULL, "Matrix is not initialized yet");
5743:     p_oth = (Mat_SeqAIJ *)(*P_oth)->data;
5744:     /* Update values in place */
5745:     PetscCall(MatSeqAIJGetArrayRead(p->A, &pd_a));
5746:     PetscCall(MatSeqAIJGetArrayRead(p->B, &po_a));
5747:     PetscCall(PetscSFBcastBegin(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5748:     PetscCall(PetscSFBcastBegin(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5749:     PetscCall(PetscSFBcastEnd(sf, MPIU_SCALAR, pd_a, p_oth->a, MPI_REPLACE));
5750:     PetscCall(PetscSFBcastEnd(osf, MPIU_SCALAR, po_a, p_oth->a, MPI_REPLACE));
5751:     PetscCall(MatSeqAIJRestoreArrayRead(p->A, &pd_a));
5752:     PetscCall(MatSeqAIJRestoreArrayRead(p->B, &po_a));
5753:   } else SETERRQ(comm, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown reuse type");
5754:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, P, 0, 0));
5755:   PetscFunctionReturn(PETSC_SUCCESS);
5756: }

5758: /*@C
5759:   MatGetBrowsOfAcols - Returns `IS` that contain rows of `B` that equal to nonzero columns of local `A`

5761:   Collective

5763:   Input Parameters:
5764: + A     - the first matrix in `MATMPIAIJ` format
5765: . B     - the second matrix in `MATMPIAIJ` format
5766: - scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5768:   Output Parameters:
5769: + rowb  - On input index sets of rows of B to extract (or `NULL`), modified on output
5770: . colb  - On input index sets of columns of B to extract (or `NULL`), modified on output
5771: - B_seq - the sequential matrix generated

5773:   Level: developer

5775: .seealso: `Mat`, `MATMPIAIJ`, `IS`, `MatReuse`
5776: @*/
5777: PetscErrorCode MatGetBrowsOfAcols(Mat A, Mat B, MatReuse scall, IS *rowb, IS *colb, Mat *B_seq)
5778: {
5779:   Mat_MPIAIJ *a = (Mat_MPIAIJ *)A->data;
5780:   PetscInt   *idx, i, start, ncols, nzA, nzB, *cmap, imark;
5781:   IS          isrowb, iscolb;
5782:   Mat        *bseq = NULL;

5784:   PetscFunctionBegin;
5785:   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 ")",
5786:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5787:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAcols, A, B, 0, 0));

5789:   if (scall == MAT_INITIAL_MATRIX) {
5790:     start = A->cmap->rstart;
5791:     cmap  = a->garray;
5792:     nzA   = a->A->cmap->n;
5793:     nzB   = a->B->cmap->n;
5794:     PetscCall(PetscMalloc1(nzA + nzB, &idx));
5795:     ncols = 0;
5796:     for (i = 0; i < nzB; i++) { /* row < local row index */
5797:       if (cmap[i] < start) idx[ncols++] = cmap[i];
5798:       else break;
5799:     }
5800:     imark = i;
5801:     for (i = 0; i < nzA; i++) idx[ncols++] = start + i;   /* local rows */
5802:     for (i = imark; i < nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5803:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, ncols, idx, PETSC_OWN_POINTER, &isrowb));
5804:     PetscCall(ISCreateStride(PETSC_COMM_SELF, B->cmap->N, 0, 1, &iscolb));
5805:   } else {
5806:     PetscCheck(rowb && colb, PETSC_COMM_SELF, PETSC_ERR_SUP, "IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5807:     isrowb = *rowb;
5808:     iscolb = *colb;
5809:     PetscCall(PetscMalloc1(1, &bseq));
5810:     bseq[0] = *B_seq;
5811:   }
5812:   PetscCall(MatCreateSubMatrices(B, 1, &isrowb, &iscolb, scall, &bseq));
5813:   *B_seq = bseq[0];
5814:   PetscCall(PetscFree(bseq));
5815:   if (!rowb) {
5816:     PetscCall(ISDestroy(&isrowb));
5817:   } else {
5818:     *rowb = isrowb;
5819:   }
5820:   if (!colb) {
5821:     PetscCall(ISDestroy(&iscolb));
5822:   } else {
5823:     *colb = iscolb;
5824:   }
5825:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAcols, A, B, 0, 0));
5826:   PetscFunctionReturn(PETSC_SUCCESS);
5827: }

5829: /*
5830:     MatGetBrowsOfAoCols_MPIAIJ - Creates a `MATSEQAIJ` matrix by taking rows of B that equal to nonzero columns
5831:     of the OFF-DIAGONAL portion of local A

5833:     Collective

5835:    Input Parameters:
5836: +    A,B - the matrices in `MATMPIAIJ` format
5837: -    scall - either `MAT_INITIAL_MATRIX` or `MAT_REUSE_MATRIX`

5839:    Output Parameter:
5840: +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5841: .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5842: .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5843: -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N

5845:     Developer Note:
5846:     This directly accesses information inside the VecScatter associated with the matrix-vector product
5847:      for this matrix. This is not desirable..

5849:     Level: developer

5851: */

5853: PetscErrorCode MatGetBrowsOfAoCols_MPIAIJ(Mat A, Mat B, MatReuse scall, PetscInt **startsj_s, PetscInt **startsj_r, MatScalar **bufa_ptr, Mat *B_oth)
5854: {
5855:   Mat_MPIAIJ        *a = (Mat_MPIAIJ *)A->data;
5856:   VecScatter         ctx;
5857:   MPI_Comm           comm;
5858:   const PetscMPIInt *rprocs, *sprocs;
5859:   PetscMPIInt        nrecvs, nsends;
5860:   const PetscInt    *srow, *rstarts, *sstarts;
5861:   PetscInt          *rowlen, *bufj, *bufJ, ncols = 0, aBn = a->B->cmap->n, row, *b_othi, *b_othj, *rvalues = NULL, *svalues = NULL, *cols, sbs, rbs;
5862:   PetscInt           i, j, k = 0, l, ll, nrows, *rstartsj = NULL, *sstartsj, len;
5863:   PetscScalar       *b_otha, *bufa, *bufA, *vals = NULL;
5864:   MPI_Request       *reqs = NULL, *rwaits = NULL, *swaits = NULL;
5865:   PetscMPIInt        size, tag, rank, nreqs;

5867:   PetscFunctionBegin;
5868:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
5869:   PetscCallMPI(MPI_Comm_size(comm, &size));

5871:   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 ")",
5872:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
5873:   PetscCall(PetscLogEventBegin(MAT_GetBrowsOfAocols, A, B, 0, 0));
5874:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

5876:   if (size == 1) {
5877:     startsj_s = NULL;
5878:     bufa_ptr  = NULL;
5879:     *B_oth    = NULL;
5880:     PetscFunctionReturn(PETSC_SUCCESS);
5881:   }

5883:   ctx = a->Mvctx;
5884:   tag = ((PetscObject)ctx)->tag;

5886:   PetscCall(VecScatterGetRemote_Private(ctx, PETSC_TRUE /*send*/, &nsends, &sstarts, &srow, &sprocs, &sbs));
5887:   /* rprocs[] must be ordered so that indices received from them are ordered in rvalues[], which is key to algorithms used in this subroutine */
5888:   PetscCall(VecScatterGetRemoteOrdered_Private(ctx, PETSC_FALSE /*recv*/, &nrecvs, &rstarts, NULL /*indices not needed*/, &rprocs, &rbs));
5889:   PetscCall(PetscMPIIntCast(nsends + nrecvs, &nreqs));
5890:   PetscCall(PetscMalloc1(nreqs, &reqs));
5891:   rwaits = reqs;
5892:   swaits = PetscSafePointerPlusOffset(reqs, nrecvs);

5894:   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5895:   if (scall == MAT_INITIAL_MATRIX) {
5896:     /* i-array */
5897:     /*  post receives */
5898:     if (nrecvs) PetscCall(PetscMalloc1(rbs * (rstarts[nrecvs] - rstarts[0]), &rvalues)); /* rstarts can be NULL when nrecvs=0 */
5899:     for (i = 0; i < nrecvs; i++) {
5900:       rowlen = rvalues + rstarts[i] * rbs;
5901:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of indices to be received */
5902:       PetscCallMPI(MPIU_Irecv(rowlen, nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5903:     }

5905:     /* pack the outgoing message */
5906:     PetscCall(PetscMalloc2(nsends + 1, &sstartsj, nrecvs + 1, &rstartsj));

5908:     sstartsj[0] = 0;
5909:     rstartsj[0] = 0;
5910:     len         = 0; /* total length of j or a array to be sent */
5911:     if (nsends) {
5912:       k = sstarts[0]; /* ATTENTION: sstarts[0] and rstarts[0] are not necessarily zero */
5913:       PetscCall(PetscMalloc1(sbs * (sstarts[nsends] - sstarts[0]), &svalues));
5914:     }
5915:     for (i = 0; i < nsends; i++) {
5916:       rowlen = svalues + (sstarts[i] - sstarts[0]) * sbs;
5917:       nrows  = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5918:       for (j = 0; j < nrows; j++) {
5919:         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5920:         for (l = 0; l < sbs; l++) {
5921:           PetscCall(MatGetRow_MPIAIJ(B, row + l, &ncols, NULL, NULL)); /* rowlength */

5923:           rowlen[j * sbs + l] = ncols;

5925:           len += ncols;
5926:           PetscCall(MatRestoreRow_MPIAIJ(B, row + l, &ncols, NULL, NULL));
5927:         }
5928:         k++;
5929:       }
5930:       PetscCallMPI(MPIU_Isend(rowlen, nrows * sbs, MPIU_INT, sprocs[i], tag, comm, swaits + i));

5932:       sstartsj[i + 1] = len; /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5933:     }
5934:     /* recvs and sends of i-array are completed */
5935:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5936:     PetscCall(PetscFree(svalues));

5938:     /* allocate buffers for sending j and a arrays */
5939:     PetscCall(PetscMalloc1(len + 1, &bufj));
5940:     PetscCall(PetscMalloc1(len + 1, &bufa));

5942:     /* create i-array of B_oth */
5943:     PetscCall(PetscMalloc1(aBn + 2, &b_othi));

5945:     b_othi[0] = 0;
5946:     len       = 0; /* total length of j or a array to be received */
5947:     k         = 0;
5948:     for (i = 0; i < nrecvs; i++) {
5949:       rowlen = rvalues + (rstarts[i] - rstarts[0]) * rbs;
5950:       nrows  = (rstarts[i + 1] - rstarts[i]) * rbs; /* num of rows to be received */
5951:       for (j = 0; j < nrows; j++) {
5952:         b_othi[k + 1] = b_othi[k] + rowlen[j];
5953:         PetscCall(PetscIntSumError(rowlen[j], len, &len));
5954:         k++;
5955:       }
5956:       rstartsj[i + 1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5957:     }
5958:     PetscCall(PetscFree(rvalues));

5960:     /* allocate space for j and a arrays of B_oth */
5961:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_othj));
5962:     PetscCall(PetscMalloc1(b_othi[aBn] + 1, &b_otha));

5964:     /* j-array */
5965:     /*  post receives of j-array */
5966:     for (i = 0; i < nrecvs; i++) {
5967:       nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
5968:       PetscCallMPI(MPIU_Irecv(b_othj + rstartsj[i], nrows, MPIU_INT, rprocs[i], tag, comm, rwaits + i));
5969:     }

5971:     /* pack the outgoing message j-array */
5972:     if (nsends) k = sstarts[0];
5973:     for (i = 0; i < nsends; i++) {
5974:       nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
5975:       bufJ  = bufj + sstartsj[i];
5976:       for (j = 0; j < nrows; j++) {
5977:         row = srow[k++] + B->rmap->range[rank]; /* global row idx */
5978:         for (ll = 0; ll < sbs; ll++) {
5979:           PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5980:           for (l = 0; l < ncols; l++) *bufJ++ = cols[l];
5981:           PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, &cols, NULL));
5982:         }
5983:       }
5984:       PetscCallMPI(MPIU_Isend(bufj + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_INT, sprocs[i], tag, comm, swaits + i));
5985:     }

5987:     /* recvs and sends of j-array are completed */
5988:     if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
5989:   } else if (scall == MAT_REUSE_MATRIX) {
5990:     sstartsj = *startsj_s;
5991:     rstartsj = *startsj_r;
5992:     bufa     = *bufa_ptr;
5993:     PetscCall(MatSeqAIJGetArrayWrite(*B_oth, &b_otha));
5994:   } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not possess an object container");

5996:   /* a-array */
5997:   /*  post receives of a-array */
5998:   for (i = 0; i < nrecvs; i++) {
5999:     nrows = rstartsj[i + 1] - rstartsj[i]; /* length of the msg received */
6000:     PetscCallMPI(MPIU_Irecv(b_otha + rstartsj[i], nrows, MPIU_SCALAR, rprocs[i], tag, comm, rwaits + i));
6001:   }

6003:   /* pack the outgoing message a-array */
6004:   if (nsends) k = sstarts[0];
6005:   for (i = 0; i < nsends; i++) {
6006:     nrows = sstarts[i + 1] - sstarts[i]; /* num of block rows */
6007:     bufA  = bufa + sstartsj[i];
6008:     for (j = 0; j < nrows; j++) {
6009:       row = srow[k++] + B->rmap->range[rank]; /* global row idx */
6010:       for (ll = 0; ll < sbs; ll++) {
6011:         PetscCall(MatGetRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
6012:         for (l = 0; l < ncols; l++) *bufA++ = vals[l];
6013:         PetscCall(MatRestoreRow_MPIAIJ(B, row + ll, &ncols, NULL, &vals));
6014:       }
6015:     }
6016:     PetscCallMPI(MPIU_Isend(bufa + sstartsj[i], sstartsj[i + 1] - sstartsj[i], MPIU_SCALAR, sprocs[i], tag, comm, swaits + i));
6017:   }
6018:   /* recvs and sends of a-array are completed */
6019:   if (nreqs) PetscCallMPI(MPI_Waitall(nreqs, reqs, MPI_STATUSES_IGNORE));
6020:   PetscCall(PetscFree(reqs));

6022:   if (scall == MAT_INITIAL_MATRIX) {
6023:     Mat_SeqAIJ *b_oth;

6025:     /* put together the new matrix */
6026:     PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, aBn, B->cmap->N, b_othi, b_othj, b_otha, B_oth));

6028:     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
6029:     /* Since these are PETSc arrays, change flags to free them as necessary. */
6030:     b_oth          = (Mat_SeqAIJ *)(*B_oth)->data;
6031:     b_oth->free_a  = PETSC_TRUE;
6032:     b_oth->free_ij = PETSC_TRUE;
6033:     b_oth->nonew   = 0;

6035:     PetscCall(PetscFree(bufj));
6036:     if (!startsj_s || !bufa_ptr) {
6037:       PetscCall(PetscFree2(sstartsj, rstartsj));
6038:       PetscCall(PetscFree(bufa_ptr));
6039:     } else {
6040:       *startsj_s = sstartsj;
6041:       *startsj_r = rstartsj;
6042:       *bufa_ptr  = bufa;
6043:     }
6044:   } else if (scall == MAT_REUSE_MATRIX) {
6045:     PetscCall(MatSeqAIJRestoreArrayWrite(*B_oth, &b_otha));
6046:   }

6048:   PetscCall(VecScatterRestoreRemote_Private(ctx, PETSC_TRUE, &nsends, &sstarts, &srow, &sprocs, &sbs));
6049:   PetscCall(VecScatterRestoreRemoteOrdered_Private(ctx, PETSC_FALSE, &nrecvs, &rstarts, NULL, &rprocs, &rbs));
6050:   PetscCall(PetscLogEventEnd(MAT_GetBrowsOfAocols, A, B, 0, 0));
6051:   PetscFunctionReturn(PETSC_SUCCESS);
6052: }

6054: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat, MatType, MatReuse, Mat *);
6055: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat, MatType, MatReuse, Mat *);
6056: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJSELL(Mat, MatType, MatReuse, Mat *);
6057: #if defined(PETSC_HAVE_MKL_SPARSE)
6058: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJMKL(Mat, MatType, MatReuse, Mat *);
6059: #endif
6060: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIBAIJ(Mat, MatType, MatReuse, Mat *);
6061: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat, MatType, MatReuse, Mat *);
6062: #if defined(PETSC_HAVE_ELEMENTAL)
6063: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat, MatType, MatReuse, Mat *);
6064: #endif
6065: #if defined(PETSC_HAVE_SCALAPACK)
6066: PETSC_INTERN PetscErrorCode MatConvert_AIJ_ScaLAPACK(Mat, MatType, MatReuse, Mat *);
6067: #endif
6068: #if defined(PETSC_HAVE_HYPRE)
6069: PETSC_INTERN PetscErrorCode MatConvert_AIJ_HYPRE(Mat, MatType, MatReuse, Mat *);
6070: #endif
6071: #if defined(PETSC_HAVE_CUDA)
6072: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCUSPARSE(Mat, MatType, MatReuse, Mat *);
6073: #endif
6074: #if defined(PETSC_HAVE_HIP)
6075: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJHIPSPARSE(Mat, MatType, MatReuse, Mat *);
6076: #endif
6077: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6078: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJKokkos(Mat, MatType, MatReuse, Mat *);
6079: #endif
6080: PETSC_INTERN PetscErrorCode MatConvert_MPIAIJ_MPISELL(Mat, MatType, MatReuse, Mat *);
6081: PETSC_INTERN PetscErrorCode MatConvert_XAIJ_IS(Mat, MatType, MatReuse, Mat *);
6082: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_IS_XAIJ(Mat);

6084: /*
6085:     Computes (B'*A')' since computing B*A directly is untenable

6087:                n                       p                          p
6088:         [             ]       [             ]         [                 ]
6089:       m [      A      ]  *  n [       B     ]   =   m [         C       ]
6090:         [             ]       [             ]         [                 ]

6092: */
6093: static PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A, Mat B, Mat C)
6094: {
6095:   Mat At, Bt, Ct;

6097:   PetscFunctionBegin;
6098:   PetscCall(MatTranspose(A, MAT_INITIAL_MATRIX, &At));
6099:   PetscCall(MatTranspose(B, MAT_INITIAL_MATRIX, &Bt));
6100:   PetscCall(MatMatMult(Bt, At, MAT_INITIAL_MATRIX, PETSC_CURRENT, &Ct));
6101:   PetscCall(MatDestroy(&At));
6102:   PetscCall(MatDestroy(&Bt));
6103:   PetscCall(MatTransposeSetPrecursor(Ct, C));
6104:   PetscCall(MatTranspose(Ct, MAT_REUSE_MATRIX, &C));
6105:   PetscCall(MatDestroy(&Ct));
6106:   PetscFunctionReturn(PETSC_SUCCESS);
6107: }

6109: static PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A, Mat B, PetscReal fill, Mat C)
6110: {
6111:   PetscBool cisdense;

6113:   PetscFunctionBegin;
6114:   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);
6115:   PetscCall(MatSetSizes(C, A->rmap->n, B->cmap->n, A->rmap->N, B->cmap->N));
6116:   PetscCall(MatSetBlockSizesFromMats(C, A, B));
6117:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATMPIDENSE, MATMPIDENSECUDA, MATMPIDENSEHIP, ""));
6118:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
6119:   PetscCall(MatSetUp(C));

6121:   C->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
6122:   PetscFunctionReturn(PETSC_SUCCESS);
6123: }

6125: static PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ_AB(Mat C)
6126: {
6127:   Mat_Product *product = C->product;
6128:   Mat          A = product->A, B = product->B;

6130:   PetscFunctionBegin;
6131:   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 ")",
6132:              A->cmap->rstart, A->cmap->rend, B->rmap->rstart, B->rmap->rend);
6133:   C->ops->matmultsymbolic = MatMatMultSymbolic_MPIDense_MPIAIJ;
6134:   C->ops->productsymbolic = MatProductSymbolic_AB;
6135:   PetscFunctionReturn(PETSC_SUCCESS);
6136: }

6138: PETSC_INTERN PetscErrorCode MatProductSetFromOptions_MPIDense_MPIAIJ(Mat C)
6139: {
6140:   Mat_Product *product = C->product;

6142:   PetscFunctionBegin;
6143:   if (product->type == MATPRODUCT_AB) PetscCall(MatProductSetFromOptions_MPIDense_MPIAIJ_AB(C));
6144:   PetscFunctionReturn(PETSC_SUCCESS);
6145: }

6147: /*
6148:    Merge two sets of sorted nonzeros and return a CSR for the merged (sequential) matrix

6150:   Input Parameters:

6152:     j1,rowBegin1,rowEnd1,jmap1: describe the first set of nonzeros (Set1)
6153:     j2,rowBegin2,rowEnd2,jmap2: describe the second set of nonzeros (Set2)

6155:     mat: both sets' nonzeros are on m rows, where m is the number of local rows of the matrix mat

6157:     For Set1, j1[] contains column indices of the nonzeros.
6158:     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
6159:     respectively (note rowEnd1[k] is not necessarily equal to rwoBegin1[k+1]). Indices in this range of j1[] are sorted,
6160:     but might have repeats. jmap1[t+1] - jmap1[t] is the number of repeats for the t-th unique nonzero in Set1.

6162:     Similar for Set2.

6164:     This routine merges the two sets of nonzeros row by row and removes repeats.

6166:   Output Parameters: (memory is allocated by the caller)

6168:     i[],j[]: the CSR of the merged matrix, which has m rows.
6169:     imap1[]: the k-th unique nonzero in Set1 (k=0,1,...) corresponds to imap1[k]-th unique nonzero in the merged matrix.
6170:     imap2[]: similar to imap1[], but for Set2.
6171:     Note we order nonzeros row-by-row and from left to right.
6172: */
6173: 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[])
6174: {
6175:   PetscInt   r, m; /* Row index of mat */
6176:   PetscCount t, t1, t2, b1, e1, b2, e2;

6178:   PetscFunctionBegin;
6179:   PetscCall(MatGetLocalSize(mat, &m, NULL));
6180:   t1 = t2 = t = 0; /* Count unique nonzeros of in Set1, Set1 and the merged respectively */
6181:   i[0]        = 0;
6182:   for (r = 0; r < m; r++) { /* Do row by row merging */
6183:     b1 = rowBegin1[r];
6184:     e1 = rowEnd1[r];
6185:     b2 = rowBegin2[r];
6186:     e2 = rowEnd2[r];
6187:     while (b1 < e1 && b2 < e2) {
6188:       if (j1[b1] == j2[b2]) { /* Same column index and hence same nonzero */
6189:         j[t]      = j1[b1];
6190:         imap1[t1] = t;
6191:         imap2[t2] = t;
6192:         b1 += jmap1[t1 + 1] - jmap1[t1]; /* Jump to next unique local nonzero */
6193:         b2 += jmap2[t2 + 1] - jmap2[t2]; /* Jump to next unique remote nonzero */
6194:         t1++;
6195:         t2++;
6196:         t++;
6197:       } else if (j1[b1] < j2[b2]) {
6198:         j[t]      = j1[b1];
6199:         imap1[t1] = t;
6200:         b1 += jmap1[t1 + 1] - jmap1[t1];
6201:         t1++;
6202:         t++;
6203:       } else {
6204:         j[t]      = j2[b2];
6205:         imap2[t2] = t;
6206:         b2 += jmap2[t2 + 1] - jmap2[t2];
6207:         t2++;
6208:         t++;
6209:       }
6210:     }
6211:     /* Merge the remaining in either j1[] or j2[] */
6212:     while (b1 < e1) {
6213:       j[t]      = j1[b1];
6214:       imap1[t1] = t;
6215:       b1 += jmap1[t1 + 1] - jmap1[t1];
6216:       t1++;
6217:       t++;
6218:     }
6219:     while (b2 < e2) {
6220:       j[t]      = j2[b2];
6221:       imap2[t2] = t;
6222:       b2 += jmap2[t2 + 1] - jmap2[t2];
6223:       t2++;
6224:       t++;
6225:     }
6226:     PetscCall(PetscIntCast(t, i + r + 1));
6227:   }
6228:   PetscFunctionReturn(PETSC_SUCCESS);
6229: }

6231: /*
6232:   Split nonzeros in a block of local rows into two subsets: those in the diagonal block and those in the off-diagonal block

6234:   Input Parameters:
6235:     mat: an MPI matrix that provides row and column layout information for splitting. Let's say its number of local rows is m.
6236:     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[]
6237:       respectively, along with a permutation array perm[]. Length of the i[],j[],perm[] arrays is n.

6239:       i[] is already sorted, but within a row, j[] is not sorted and might have repeats.
6240:       i[] might contain negative indices at the beginning, which means the corresponding entries should be ignored in the splitting.

6242:   Output Parameters:
6243:     j[],perm[]: the routine needs to sort j[] within each row along with perm[].
6244:     rowBegin[],rowMid[],rowEnd[]: of length m, and the memory is preallocated and zeroed by the caller.
6245:       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,
6246:       and [rowMid[r],rowEnd[r]) point to begin/end entries of row r of the off-diagonal block.

6248:     Aperm[],Ajmap[],Atot,Annz: Arrays are allocated by this routine.
6249:       Atot: number of entries belonging to the diagonal block.
6250:       Annz: number of unique nonzeros belonging to the diagonal block.
6251:       Aperm[Atot] stores values from perm[] for entries belonging to the diagonal block. Length of Aperm[] is Atot, though it may also count
6252:         repeats (i.e., same 'i,j' pair).
6253:       Ajmap[Annz+1] stores the number of repeats of each unique entry belonging to the diagonal block. More precisely, Ajmap[t+1] - Ajmap[t]
6254:         is the number of repeats for the t-th unique entry in the diagonal block. Ajmap[0] is always 0.

6256:       Atot: number of entries belonging to the diagonal block
6257:       Annz: number of unique nonzeros belonging to the diagonal block.

6259:     Bperm[], Bjmap[], Btot, Bnnz are similar but for the off-diagonal block.

6261:     Aperm[],Bperm[],Ajmap[] and Bjmap[] are allocated separately by this routine with PetscMalloc1().
6262: */
6263: 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_)
6264: {
6265:   PetscInt    cstart, cend, rstart, rend, row, col;
6266:   PetscCount  Atot = 0, Btot = 0; /* Total number of nonzeros in the diagonal and off-diagonal blocks */
6267:   PetscCount  Annz = 0, Bnnz = 0; /* Number of unique nonzeros in the diagonal and off-diagonal blocks */
6268:   PetscCount  k, m, p, q, r, s, mid;
6269:   PetscCount *Aperm, *Bperm, *Ajmap, *Bjmap;

6271:   PetscFunctionBegin;
6272:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6273:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6274:   m = rend - rstart;

6276:   /* Skip negative rows */
6277:   for (k = 0; k < n; k++)
6278:     if (i[k] >= 0) break;

6280:   /* Process [k,n): sort and partition each local row into diag and offdiag portions,
6281:      fill rowBegin[], rowMid[], rowEnd[], and count Atot, Btot, Annz, Bnnz.
6282:   */
6283:   while (k < n) {
6284:     row = i[k];
6285:     /* Entries in [k,s) are in one row. Shift diagonal block col indices so that diag is ahead of offdiag after sorting the row */
6286:     for (s = k; s < n; s++)
6287:       if (i[s] != row) break;

6289:     /* Shift diag columns to range of [-PETSC_INT_MAX, -1] */
6290:     for (p = k; p < s; p++) {
6291:       if (j[p] >= cstart && j[p] < cend) j[p] -= PETSC_INT_MAX;
6292:       else PetscAssert((j[p] >= 0) && (j[p] <= mat->cmap->N), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column index %" PetscInt_FMT " is out of range", j[p]);
6293:     }
6294:     PetscCall(PetscSortIntWithCountArray(s - k, j + k, perm + k));
6295:     PetscCall(PetscSortedIntUpperBound(j, k, s, -1, &mid)); /* Separate [k,s) into [k,mid) for diag and [mid,s) for offdiag */
6296:     rowBegin[row - rstart] = k;
6297:     rowMid[row - rstart]   = mid;
6298:     rowEnd[row - rstart]   = s;

6300:     /* Count nonzeros of this diag/offdiag row, which might have repeats */
6301:     Atot += mid - k;
6302:     Btot += s - mid;

6304:     /* Count unique nonzeros of this diag row */
6305:     for (p = k; p < mid;) {
6306:       col = j[p];
6307:       do {
6308:         j[p] += PETSC_INT_MAX; /* Revert the modified diagonal indices */
6309:         p++;
6310:       } while (p < mid && j[p] == col);
6311:       Annz++;
6312:     }

6314:     /* Count unique nonzeros of this offdiag row */
6315:     for (p = mid; p < s;) {
6316:       col = j[p];
6317:       do {
6318:         p++;
6319:       } while (p < s && j[p] == col);
6320:       Bnnz++;
6321:     }
6322:     k = s;
6323:   }

6325:   /* Allocation according to Atot, Btot, Annz, Bnnz */
6326:   PetscCall(PetscMalloc1(Atot, &Aperm));
6327:   PetscCall(PetscMalloc1(Btot, &Bperm));
6328:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap));
6329:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap));

6331:   /* Re-scan indices and copy diag/offdiag permutation indices to Aperm, Bperm and also fill Ajmap and Bjmap */
6332:   Ajmap[0] = Bjmap[0] = Atot = Btot = Annz = Bnnz = 0;
6333:   for (r = 0; r < m; r++) {
6334:     k   = rowBegin[r];
6335:     mid = rowMid[r];
6336:     s   = rowEnd[r];
6337:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Aperm, Atot), PetscSafePointerPlusOffset(perm, k), mid - k));
6338:     PetscCall(PetscArraycpy(PetscSafePointerPlusOffset(Bperm, Btot), PetscSafePointerPlusOffset(perm, mid), s - mid));
6339:     Atot += mid - k;
6340:     Btot += s - mid;

6342:     /* Scan column indices in this row and find out how many repeats each unique nonzero has */
6343:     for (p = k; p < mid;) {
6344:       col = j[p];
6345:       q   = p;
6346:       do {
6347:         p++;
6348:       } while (p < mid && j[p] == col);
6349:       Ajmap[Annz + 1] = Ajmap[Annz] + (p - q);
6350:       Annz++;
6351:     }

6353:     for (p = mid; p < s;) {
6354:       col = j[p];
6355:       q   = p;
6356:       do {
6357:         p++;
6358:       } while (p < s && j[p] == col);
6359:       Bjmap[Bnnz + 1] = Bjmap[Bnnz] + (p - q);
6360:       Bnnz++;
6361:     }
6362:   }
6363:   /* Output */
6364:   *Aperm_ = Aperm;
6365:   *Annz_  = Annz;
6366:   *Atot_  = Atot;
6367:   *Ajmap_ = Ajmap;
6368:   *Bperm_ = Bperm;
6369:   *Bnnz_  = Bnnz;
6370:   *Btot_  = Btot;
6371:   *Bjmap_ = Bjmap;
6372:   PetscFunctionReturn(PETSC_SUCCESS);
6373: }

6375: /*
6376:   Expand the jmap[] array to make a new one in view of nonzeros in the merged matrix

6378:   Input Parameters:
6379:     nnz1: number of unique nonzeros in a set that was used to produce imap[], jmap[]
6380:     nnz:  number of unique nonzeros in the merged matrix
6381:     imap[nnz1]: i-th nonzero in the set is the imap[i]-th nonzero in the merged matrix
6382:     jmap[nnz1+1]: i-th nonzero in the set has jmap[i+1] - jmap[i] repeats in the set

6384:   Output Parameter: (memory is allocated by the caller)
6385:     jmap_new[nnz+1]: i-th nonzero in the merged matrix has jmap_new[i+1] - jmap_new[i] repeats in the set

6387:   Example:
6388:     nnz1 = 4
6389:     nnz  = 6
6390:     imap = [1,3,4,5]
6391:     jmap = [0,3,5,6,7]
6392:    then,
6393:     jmap_new = [0,0,3,3,5,6,7]
6394: */
6395: static PetscErrorCode ExpandJmap_Internal(PetscCount nnz1, PetscCount nnz, const PetscCount imap[], const PetscCount jmap[], PetscCount jmap_new[])
6396: {
6397:   PetscCount k, p;

6399:   PetscFunctionBegin;
6400:   jmap_new[0] = 0;
6401:   p           = nnz;                /* p loops over jmap_new[] backwards */
6402:   for (k = nnz1 - 1; k >= 0; k--) { /* k loops over imap[] */
6403:     for (; p > imap[k]; p--) jmap_new[p] = jmap[k + 1];
6404:   }
6405:   for (; p >= 0; p--) jmap_new[p] = jmap[0];
6406:   PetscFunctionReturn(PETSC_SUCCESS);
6407: }

6409: static PetscErrorCode MatCOOStructDestroy_MPIAIJ(void **data)
6410: {
6411:   MatCOOStruct_MPIAIJ *coo = (MatCOOStruct_MPIAIJ *)*data;

6413:   PetscFunctionBegin;
6414:   PetscCall(PetscSFDestroy(&coo->sf));
6415:   PetscCall(PetscFree(coo->Aperm1));
6416:   PetscCall(PetscFree(coo->Bperm1));
6417:   PetscCall(PetscFree(coo->Ajmap1));
6418:   PetscCall(PetscFree(coo->Bjmap1));
6419:   PetscCall(PetscFree(coo->Aimap2));
6420:   PetscCall(PetscFree(coo->Bimap2));
6421:   PetscCall(PetscFree(coo->Aperm2));
6422:   PetscCall(PetscFree(coo->Bperm2));
6423:   PetscCall(PetscFree(coo->Ajmap2));
6424:   PetscCall(PetscFree(coo->Bjmap2));
6425:   PetscCall(PetscFree(coo->Cperm1));
6426:   PetscCall(PetscFree2(coo->sendbuf, coo->recvbuf));
6427:   PetscCall(PetscFree(coo));
6428:   PetscFunctionReturn(PETSC_SUCCESS);
6429: }

6431: PetscErrorCode MatSetPreallocationCOO_MPIAIJ(Mat mat, PetscCount coo_n, PetscInt coo_i[], PetscInt coo_j[])
6432: {
6433:   MPI_Comm             comm;
6434:   PetscMPIInt          rank, size;
6435:   PetscInt             m, n, M, N, rstart, rend, cstart, cend; /* Sizes, indices of row/col, therefore with type PetscInt */
6436:   PetscCount           k, p, q, rem;                           /* Loop variables over coo arrays */
6437:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6438:   PetscContainer       container;
6439:   MatCOOStruct_MPIAIJ *coo;

6441:   PetscFunctionBegin;
6442:   PetscCall(PetscFree(mpiaij->garray));
6443:   PetscCall(VecDestroy(&mpiaij->lvec));
6444: #if defined(PETSC_USE_CTABLE)
6445:   PetscCall(PetscHMapIDestroy(&mpiaij->colmap));
6446: #else
6447:   PetscCall(PetscFree(mpiaij->colmap));
6448: #endif
6449:   PetscCall(VecScatterDestroy(&mpiaij->Mvctx));
6450:   mat->assembled     = PETSC_FALSE;
6451:   mat->was_assembled = PETSC_FALSE;

6453:   PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
6454:   PetscCallMPI(MPI_Comm_size(comm, &size));
6455:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
6456:   PetscCall(PetscLayoutSetUp(mat->rmap));
6457:   PetscCall(PetscLayoutSetUp(mat->cmap));
6458:   PetscCall(PetscLayoutGetRange(mat->rmap, &rstart, &rend));
6459:   PetscCall(PetscLayoutGetRange(mat->cmap, &cstart, &cend));
6460:   PetscCall(MatGetLocalSize(mat, &m, &n));
6461:   PetscCall(MatGetSize(mat, &M, &N));

6463:   /* Sort (i,j) by row along with a permutation array, so that the to-be-ignored */
6464:   /* entries come first, then local rows, then remote rows.                     */
6465:   PetscCount n1 = coo_n, *perm1;
6466:   PetscInt  *i1 = coo_i, *j1 = coo_j;

6468:   PetscCall(PetscMalloc1(n1, &perm1));
6469:   for (k = 0; k < n1; k++) perm1[k] = k;

6471:   /* Manipulate indices so that entries with negative row or col indices will have smallest
6472:      row indices, local entries will have greater but negative row indices, and remote entries
6473:      will have positive row indices.
6474:   */
6475:   for (k = 0; k < n1; k++) {
6476:     if (i1[k] < 0 || j1[k] < 0) i1[k] = PETSC_INT_MIN;                /* e.g., -2^31, minimal to move them ahead */
6477:     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] */
6478:     else {
6479:       PetscCheck(!mat->nooffprocentries, PETSC_COMM_SELF, PETSC_ERR_USER_INPUT, "MAT_NO_OFF_PROC_ENTRIES is set but insert to remote rows");
6480:       if (mpiaij->donotstash) i1[k] = PETSC_INT_MIN; /* Ignore offproc entries as if they had negative indices */
6481:     }
6482:   }

6484:   /* Sort by row; after that, [0,k) have ignored entries, [k,rem) have local rows and [rem,n1) have remote rows */
6485:   PetscCall(PetscSortIntWithIntCountArrayPair(n1, i1, j1, perm1));

6487:   /* Advance k to the first entry we need to take care of */
6488:   for (k = 0; k < n1; k++)
6489:     if (i1[k] > PETSC_INT_MIN) break;
6490:   PetscCount i1start = k;

6492:   PetscCall(PetscSortedIntUpperBound(i1, k, n1, rend - 1 - PETSC_INT_MAX, &rem)); /* rem is upper bound of the last local row */
6493:   for (; k < rem; k++) i1[k] += PETSC_INT_MAX;                                    /* Revert row indices of local rows*/

6495:   /*           Send remote rows to their owner                                  */
6496:   /* Find which rows should be sent to which remote ranks*/
6497:   PetscInt        nsend = 0; /* Number of MPI ranks to send data to */
6498:   PetscMPIInt    *sendto;    /* [nsend], storing remote ranks */
6499:   PetscInt       *nentries;  /* [nsend], storing number of entries sent to remote ranks; Assume PetscInt is big enough for this count, and error if not */
6500:   const PetscInt *ranges;
6501:   PetscInt        maxNsend = size >= 128 ? 128 : size; /* Assume max 128 neighbors; realloc when needed */

6503:   PetscCall(PetscLayoutGetRanges(mat->rmap, &ranges));
6504:   PetscCall(PetscMalloc2(maxNsend, &sendto, maxNsend, &nentries));
6505:   for (k = rem; k < n1;) {
6506:     PetscMPIInt owner;
6507:     PetscInt    firstRow, lastRow;

6509:     /* Locate a row range */
6510:     firstRow = i1[k]; /* first row of this owner */
6511:     PetscCall(PetscLayoutFindOwner(mat->rmap, firstRow, &owner));
6512:     lastRow = ranges[owner + 1] - 1; /* last row of this owner */

6514:     /* Find the first index 'p' in [k,n) with i[p] belonging to next owner */
6515:     PetscCall(PetscSortedIntUpperBound(i1, k, n1, lastRow, &p));

6517:     /* All entries in [k,p) belong to this remote owner */
6518:     if (nsend >= maxNsend) { /* Double the remote ranks arrays if not long enough */
6519:       PetscMPIInt *sendto2;
6520:       PetscInt    *nentries2;
6521:       PetscInt     maxNsend2 = (maxNsend <= size / 2) ? maxNsend * 2 : size;

6523:       PetscCall(PetscMalloc2(maxNsend2, &sendto2, maxNsend2, &nentries2));
6524:       PetscCall(PetscArraycpy(sendto2, sendto, maxNsend));
6525:       PetscCall(PetscArraycpy(nentries2, nentries2, maxNsend + 1));
6526:       PetscCall(PetscFree2(sendto, nentries2));
6527:       sendto   = sendto2;
6528:       nentries = nentries2;
6529:       maxNsend = maxNsend2;
6530:     }
6531:     sendto[nsend] = owner;
6532:     PetscCall(PetscIntCast(p - k, &nentries[nsend]));
6533:     nsend++;
6534:     k = p;
6535:   }

6537:   /* Build 1st SF to know offsets on remote to send data */
6538:   PetscSF      sf1;
6539:   PetscInt     nroots = 1, nroots2 = 0;
6540:   PetscInt     nleaves = nsend, nleaves2 = 0;
6541:   PetscInt    *offsets;
6542:   PetscSFNode *iremote;

6544:   PetscCall(PetscSFCreate(comm, &sf1));
6545:   PetscCall(PetscMalloc1(nsend, &iremote));
6546:   PetscCall(PetscMalloc1(nsend, &offsets));
6547:   for (k = 0; k < nsend; k++) {
6548:     iremote[k].rank  = sendto[k];
6549:     iremote[k].index = 0;
6550:     nleaves2 += nentries[k];
6551:     PetscCheck(nleaves2 >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF leaves is too large for PetscInt");
6552:   }
6553:   PetscCall(PetscSFSetGraph(sf1, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));
6554:   PetscCall(PetscSFFetchAndOpWithMemTypeBegin(sf1, MPIU_INT, PETSC_MEMTYPE_HOST, &nroots2 /*rootdata*/, PETSC_MEMTYPE_HOST, nentries /*leafdata*/, PETSC_MEMTYPE_HOST, offsets /*leafupdate*/, MPI_SUM));
6555:   PetscCall(PetscSFFetchAndOpEnd(sf1, MPIU_INT, &nroots2, nentries, offsets, MPI_SUM)); /* Would nroots2 overflow, we check offsets[] below */
6556:   PetscCall(PetscSFDestroy(&sf1));
6557:   PetscAssert(nleaves2 == n1 - rem, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nleaves2 %" PetscInt_FMT " != number of remote entries %" PetscCount_FMT, nleaves2, n1 - rem);

6559:   /* Build 2nd SF to send remote COOs to their owner */
6560:   PetscSF sf2;
6561:   nroots  = nroots2;
6562:   nleaves = nleaves2;
6563:   PetscCall(PetscSFCreate(comm, &sf2));
6564:   PetscCall(PetscSFSetFromOptions(sf2));
6565:   PetscCall(PetscMalloc1(nleaves, &iremote));
6566:   p = 0;
6567:   for (k = 0; k < nsend; k++) {
6568:     PetscCheck(offsets[k] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of SF roots is too large for PetscInt");
6569:     for (q = 0; q < nentries[k]; q++, p++) {
6570:       iremote[p].rank = sendto[k];
6571:       PetscCall(PetscIntCast(offsets[k] + q, &iremote[p].index));
6572:     }
6573:   }
6574:   PetscCall(PetscSFSetGraph(sf2, nroots, nleaves, NULL, PETSC_OWN_POINTER, iremote, PETSC_OWN_POINTER));

6576:   /* Send the remote COOs to their owner */
6577:   PetscInt    n2 = nroots, *i2, *j2; /* Buffers for received COOs from other ranks, along with a permutation array */
6578:   PetscCount *perm2;                 /* Though PetscInt is enough for remote entries, we use PetscCount here as we want to reuse MatSplitEntries_Internal() */
6579:   PetscCall(PetscMalloc3(n2, &i2, n2, &j2, n2, &perm2));
6580:   PetscAssert(rem == 0 || i1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6581:   PetscAssert(rem == 0 || j1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6582:   PetscInt *i1prem = PetscSafePointerPlusOffset(i1, rem);
6583:   PetscInt *j1prem = PetscSafePointerPlusOffset(j1, rem);
6584:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, i1prem, PETSC_MEMTYPE_HOST, i2, MPI_REPLACE));
6585:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, i1prem, i2, MPI_REPLACE));
6586:   PetscCall(PetscSFReduceWithMemTypeBegin(sf2, MPIU_INT, PETSC_MEMTYPE_HOST, j1prem, PETSC_MEMTYPE_HOST, j2, MPI_REPLACE));
6587:   PetscCall(PetscSFReduceEnd(sf2, MPIU_INT, j1prem, j2, MPI_REPLACE));

6589:   PetscCall(PetscFree(offsets));
6590:   PetscCall(PetscFree2(sendto, nentries));

6592:   /* Sort received COOs by row along with the permutation array     */
6593:   for (k = 0; k < n2; k++) perm2[k] = k;
6594:   PetscCall(PetscSortIntWithIntCountArrayPair(n2, i2, j2, perm2));

6596:   /* sf2 only sends contiguous leafdata to contiguous rootdata. We record the permutation which will be used to fill leafdata */
6597:   PetscCount *Cperm1;
6598:   PetscAssert(rem == 0 || perm1 != NULL, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Cannot add nonzero offset to null");
6599:   PetscCount *perm1prem = PetscSafePointerPlusOffset(perm1, rem);
6600:   PetscCall(PetscMalloc1(nleaves, &Cperm1));
6601:   PetscCall(PetscArraycpy(Cperm1, perm1prem, nleaves));

6603:   /* Support for HYPRE matrices, kind of a hack.
6604:      Swap min column with diagonal so that diagonal values will go first */
6605:   PetscBool hypre;
6606:   PetscCall(PetscStrcmp("_internal_COO_mat_for_hypre", ((PetscObject)mat)->name, &hypre));
6607:   if (hypre) {
6608:     PetscInt *minj;
6609:     PetscBT   hasdiag;

6611:     PetscCall(PetscBTCreate(m, &hasdiag));
6612:     PetscCall(PetscMalloc1(m, &minj));
6613:     for (k = 0; k < m; k++) minj[k] = PETSC_INT_MAX;
6614:     for (k = i1start; k < rem; k++) {
6615:       if (j1[k] < cstart || j1[k] >= cend) continue;
6616:       const PetscInt rindex = i1[k] - rstart;
6617:       if ((j1[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6618:       minj[rindex] = PetscMin(minj[rindex], j1[k]);
6619:     }
6620:     for (k = 0; k < n2; k++) {
6621:       if (j2[k] < cstart || j2[k] >= cend) continue;
6622:       const PetscInt rindex = i2[k] - rstart;
6623:       if ((j2[k] - cstart) == rindex) PetscCall(PetscBTSet(hasdiag, rindex));
6624:       minj[rindex] = PetscMin(minj[rindex], j2[k]);
6625:     }
6626:     for (k = i1start; k < rem; k++) {
6627:       const PetscInt rindex = i1[k] - rstart;
6628:       if (j1[k] < cstart || j1[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6629:       if (j1[k] == minj[rindex]) j1[k] = i1[k] + (cstart - rstart);
6630:       else if ((j1[k] - cstart) == rindex) j1[k] = minj[rindex];
6631:     }
6632:     for (k = 0; k < n2; k++) {
6633:       const PetscInt rindex = i2[k] - rstart;
6634:       if (j2[k] < cstart || j2[k] >= cend || !PetscBTLookup(hasdiag, rindex)) continue;
6635:       if (j2[k] == minj[rindex]) j2[k] = i2[k] + (cstart - rstart);
6636:       else if ((j2[k] - cstart) == rindex) j2[k] = minj[rindex];
6637:     }
6638:     PetscCall(PetscBTDestroy(&hasdiag));
6639:     PetscCall(PetscFree(minj));
6640:   }

6642:   /* Split local COOs and received COOs into diag/offdiag portions */
6643:   PetscCount *rowBegin1, *rowMid1, *rowEnd1;
6644:   PetscCount *Ajmap1, *Aperm1, *Bjmap1, *Bperm1;
6645:   PetscCount  Annz1, Bnnz1, Atot1, Btot1;
6646:   PetscCount *rowBegin2, *rowMid2, *rowEnd2;
6647:   PetscCount *Ajmap2, *Aperm2, *Bjmap2, *Bperm2;
6648:   PetscCount  Annz2, Bnnz2, Atot2, Btot2;

6650:   PetscCall(PetscCalloc3(m, &rowBegin1, m, &rowMid1, m, &rowEnd1));
6651:   PetscCall(PetscCalloc3(m, &rowBegin2, m, &rowMid2, m, &rowEnd2));
6652:   PetscCall(MatSplitEntries_Internal(mat, rem, i1, j1, perm1, rowBegin1, rowMid1, rowEnd1, &Atot1, &Aperm1, &Annz1, &Ajmap1, &Btot1, &Bperm1, &Bnnz1, &Bjmap1));
6653:   PetscCall(MatSplitEntries_Internal(mat, n2, i2, j2, perm2, rowBegin2, rowMid2, rowEnd2, &Atot2, &Aperm2, &Annz2, &Ajmap2, &Btot2, &Bperm2, &Bnnz2, &Bjmap2));

6655:   /* Merge local COOs with received COOs: diag with diag, offdiag with offdiag */
6656:   PetscInt *Ai, *Bi;
6657:   PetscInt *Aj, *Bj;

6659:   PetscCall(PetscMalloc1(m + 1, &Ai));
6660:   PetscCall(PetscMalloc1(m + 1, &Bi));
6661:   PetscCall(PetscMalloc1(Annz1 + Annz2, &Aj)); /* Since local and remote entries might have dups, we might allocate excess memory */
6662:   PetscCall(PetscMalloc1(Bnnz1 + Bnnz2, &Bj));

6664:   PetscCount *Aimap1, *Bimap1, *Aimap2, *Bimap2;
6665:   PetscCall(PetscMalloc1(Annz1, &Aimap1));
6666:   PetscCall(PetscMalloc1(Bnnz1, &Bimap1));
6667:   PetscCall(PetscMalloc1(Annz2, &Aimap2));
6668:   PetscCall(PetscMalloc1(Bnnz2, &Bimap2));

6670:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowBegin1, rowMid1, rowBegin2, rowMid2, Ajmap1, Ajmap2, Aimap1, Aimap2, Ai, Aj));
6671:   PetscCall(MatMergeEntries_Internal(mat, j1, j2, rowMid1, rowEnd1, rowMid2, rowEnd2, Bjmap1, Bjmap2, Bimap1, Bimap2, Bi, Bj));

6673:   /* Expand Ajmap1/Bjmap1 to make them based off nonzeros in A/B, since we     */
6674:   /* expect nonzeros in A/B most likely have local contributing entries        */
6675:   PetscInt    Annz = Ai[m];
6676:   PetscInt    Bnnz = Bi[m];
6677:   PetscCount *Ajmap1_new, *Bjmap1_new;

6679:   PetscCall(PetscMalloc1(Annz + 1, &Ajmap1_new));
6680:   PetscCall(PetscMalloc1(Bnnz + 1, &Bjmap1_new));

6682:   PetscCall(ExpandJmap_Internal(Annz1, Annz, Aimap1, Ajmap1, Ajmap1_new));
6683:   PetscCall(ExpandJmap_Internal(Bnnz1, Bnnz, Bimap1, Bjmap1, Bjmap1_new));

6685:   PetscCall(PetscFree(Aimap1));
6686:   PetscCall(PetscFree(Ajmap1));
6687:   PetscCall(PetscFree(Bimap1));
6688:   PetscCall(PetscFree(Bjmap1));
6689:   PetscCall(PetscFree3(rowBegin1, rowMid1, rowEnd1));
6690:   PetscCall(PetscFree3(rowBegin2, rowMid2, rowEnd2));
6691:   PetscCall(PetscFree(perm1));
6692:   PetscCall(PetscFree3(i2, j2, perm2));

6694:   Ajmap1 = Ajmap1_new;
6695:   Bjmap1 = Bjmap1_new;

6697:   /* Reallocate Aj, Bj once we know actual numbers of unique nonzeros in A and B */
6698:   if (Annz < Annz1 + Annz2) {
6699:     PetscInt *Aj_new;
6700:     PetscCall(PetscMalloc1(Annz, &Aj_new));
6701:     PetscCall(PetscArraycpy(Aj_new, Aj, Annz));
6702:     PetscCall(PetscFree(Aj));
6703:     Aj = Aj_new;
6704:   }

6706:   if (Bnnz < Bnnz1 + Bnnz2) {
6707:     PetscInt *Bj_new;
6708:     PetscCall(PetscMalloc1(Bnnz, &Bj_new));
6709:     PetscCall(PetscArraycpy(Bj_new, Bj, Bnnz));
6710:     PetscCall(PetscFree(Bj));
6711:     Bj = Bj_new;
6712:   }

6714:   /* Create new submatrices for on-process and off-process coupling                  */
6715:   PetscScalar     *Aa, *Ba;
6716:   MatType          rtype;
6717:   Mat_SeqAIJ      *a, *b;
6718:   PetscObjectState state;
6719:   PetscCall(PetscCalloc1(Annz, &Aa)); /* Zero matrix on device */
6720:   PetscCall(PetscCalloc1(Bnnz, &Ba));
6721:   /* make Aj[] local, i.e, based off the start column of the diagonal portion */
6722:   if (cstart) {
6723:     for (k = 0; k < Annz; k++) Aj[k] -= cstart;
6724:   }

6726:   PetscCall(MatGetRootType_Private(mat, &rtype));

6728:   MatSeqXAIJGetOptions_Private(mpiaij->A);
6729:   PetscCall(MatDestroy(&mpiaij->A));
6730:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, Ai, Aj, Aa, &mpiaij->A));
6731:   PetscCall(MatSetBlockSizesFromMats(mpiaij->A, mat, mat));
6732:   MatSeqXAIJRestoreOptions_Private(mpiaij->A);

6734:   MatSeqXAIJGetOptions_Private(mpiaij->B);
6735:   PetscCall(MatDestroy(&mpiaij->B));
6736:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, mat->cmap->N, Bi, Bj, Ba, &mpiaij->B));
6737:   PetscCall(MatSetBlockSizesFromMats(mpiaij->B, mat, mat));
6738:   MatSeqXAIJRestoreOptions_Private(mpiaij->B);

6740:   PetscCall(MatSetUpMultiply_MPIAIJ(mat));
6741:   mat->was_assembled = PETSC_TRUE; // was_assembled in effect means the Mvctx is built; doing so avoids redundant MatSetUpMultiply_MPIAIJ
6742:   state              = mpiaij->A->nonzerostate + mpiaij->B->nonzerostate;
6743:   PetscCallMPI(MPIU_Allreduce(&state, &mat->nonzerostate, 1, MPIU_INT64, MPI_SUM, PetscObjectComm((PetscObject)mat)));

6745:   a          = (Mat_SeqAIJ *)mpiaij->A->data;
6746:   b          = (Mat_SeqAIJ *)mpiaij->B->data;
6747:   a->free_a  = PETSC_TRUE;
6748:   a->free_ij = PETSC_TRUE;
6749:   b->free_a  = PETSC_TRUE;
6750:   b->free_ij = PETSC_TRUE;
6751:   a->maxnz   = a->nz;
6752:   b->maxnz   = b->nz;

6754:   /* conversion must happen AFTER multiply setup */
6755:   PetscCall(MatConvert(mpiaij->A, rtype, MAT_INPLACE_MATRIX, &mpiaij->A));
6756:   PetscCall(MatConvert(mpiaij->B, rtype, MAT_INPLACE_MATRIX, &mpiaij->B));
6757:   PetscCall(VecDestroy(&mpiaij->lvec));
6758:   PetscCall(MatCreateVecs(mpiaij->B, &mpiaij->lvec, NULL));

6760:   // Put the COO struct in a container and then attach that to the matrix
6761:   PetscCall(PetscMalloc1(1, &coo));
6762:   coo->n       = coo_n;
6763:   coo->sf      = sf2;
6764:   coo->sendlen = nleaves;
6765:   coo->recvlen = nroots;
6766:   coo->Annz    = Annz;
6767:   coo->Bnnz    = Bnnz;
6768:   coo->Annz2   = Annz2;
6769:   coo->Bnnz2   = Bnnz2;
6770:   coo->Atot1   = Atot1;
6771:   coo->Atot2   = Atot2;
6772:   coo->Btot1   = Btot1;
6773:   coo->Btot2   = Btot2;
6774:   coo->Ajmap1  = Ajmap1;
6775:   coo->Aperm1  = Aperm1;
6776:   coo->Bjmap1  = Bjmap1;
6777:   coo->Bperm1  = Bperm1;
6778:   coo->Aimap2  = Aimap2;
6779:   coo->Ajmap2  = Ajmap2;
6780:   coo->Aperm2  = Aperm2;
6781:   coo->Bimap2  = Bimap2;
6782:   coo->Bjmap2  = Bjmap2;
6783:   coo->Bperm2  = Bperm2;
6784:   coo->Cperm1  = Cperm1;
6785:   // Allocate in preallocation. If not used, it has zero cost on host
6786:   PetscCall(PetscMalloc2(coo->sendlen, &coo->sendbuf, coo->recvlen, &coo->recvbuf));
6787:   PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &container));
6788:   PetscCall(PetscContainerSetPointer(container, coo));
6789:   PetscCall(PetscContainerSetCtxDestroy(container, MatCOOStructDestroy_MPIAIJ));
6790:   PetscCall(PetscObjectCompose((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject)container));
6791:   PetscCall(PetscContainerDestroy(&container));
6792:   PetscFunctionReturn(PETSC_SUCCESS);
6793: }

6795: static PetscErrorCode MatSetValuesCOO_MPIAIJ(Mat mat, const PetscScalar v[], InsertMode imode)
6796: {
6797:   Mat_MPIAIJ          *mpiaij = (Mat_MPIAIJ *)mat->data;
6798:   Mat                  A = mpiaij->A, B = mpiaij->B;
6799:   PetscScalar         *Aa, *Ba;
6800:   PetscScalar         *sendbuf, *recvbuf;
6801:   const PetscCount    *Ajmap1, *Ajmap2, *Aimap2;
6802:   const PetscCount    *Bjmap1, *Bjmap2, *Bimap2;
6803:   const PetscCount    *Aperm1, *Aperm2, *Bperm1, *Bperm2;
6804:   const PetscCount    *Cperm1;
6805:   PetscContainer       container;
6806:   MatCOOStruct_MPIAIJ *coo;

6808:   PetscFunctionBegin;
6809:   PetscCall(PetscObjectQuery((PetscObject)mat, "__PETSc_MatCOOStruct_Host", (PetscObject *)&container));
6810:   PetscCheck(container, PetscObjectComm((PetscObject)mat), PETSC_ERR_PLIB, "Not found MatCOOStruct on this matrix");
6811:   PetscCall(PetscContainerGetPointer(container, (void **)&coo));
6812:   sendbuf = coo->sendbuf;
6813:   recvbuf = coo->recvbuf;
6814:   Ajmap1  = coo->Ajmap1;
6815:   Ajmap2  = coo->Ajmap2;
6816:   Aimap2  = coo->Aimap2;
6817:   Bjmap1  = coo->Bjmap1;
6818:   Bjmap2  = coo->Bjmap2;
6819:   Bimap2  = coo->Bimap2;
6820:   Aperm1  = coo->Aperm1;
6821:   Aperm2  = coo->Aperm2;
6822:   Bperm1  = coo->Bperm1;
6823:   Bperm2  = coo->Bperm2;
6824:   Cperm1  = coo->Cperm1;

6826:   PetscCall(MatSeqAIJGetArray(A, &Aa)); /* Might read and write matrix values */
6827:   PetscCall(MatSeqAIJGetArray(B, &Ba));

6829:   /* Pack entries to be sent to remote */
6830:   for (PetscCount i = 0; i < coo->sendlen; i++) sendbuf[i] = v[Cperm1[i]];

6832:   /* Send remote entries to their owner and overlap the communication with local computation */
6833:   PetscCall(PetscSFReduceWithMemTypeBegin(coo->sf, MPIU_SCALAR, PETSC_MEMTYPE_HOST, sendbuf, PETSC_MEMTYPE_HOST, recvbuf, MPI_REPLACE));
6834:   /* Add local entries to A and B */
6835:   for (PetscCount i = 0; i < coo->Annz; i++) { /* All nonzeros in A are either zero'ed or added with a value (i.e., initialized) */
6836:     PetscScalar sum = 0.0;                     /* Do partial summation first to improve numerical stability */
6837:     for (PetscCount k = Ajmap1[i]; k < Ajmap1[i + 1]; k++) sum += v[Aperm1[k]];
6838:     Aa[i] = (imode == INSERT_VALUES ? 0.0 : Aa[i]) + sum;
6839:   }
6840:   for (PetscCount i = 0; i < coo->Bnnz; i++) {
6841:     PetscScalar sum = 0.0;
6842:     for (PetscCount k = Bjmap1[i]; k < Bjmap1[i + 1]; k++) sum += v[Bperm1[k]];
6843:     Ba[i] = (imode == INSERT_VALUES ? 0.0 : Ba[i]) + sum;
6844:   }
6845:   PetscCall(PetscSFReduceEnd(coo->sf, MPIU_SCALAR, sendbuf, recvbuf, MPI_REPLACE));

6847:   /* Add received remote entries to A and B */
6848:   for (PetscCount i = 0; i < coo->Annz2; i++) {
6849:     for (PetscCount k = Ajmap2[i]; k < Ajmap2[i + 1]; k++) Aa[Aimap2[i]] += recvbuf[Aperm2[k]];
6850:   }
6851:   for (PetscCount i = 0; i < coo->Bnnz2; i++) {
6852:     for (PetscCount k = Bjmap2[i]; k < Bjmap2[i + 1]; k++) Ba[Bimap2[i]] += recvbuf[Bperm2[k]];
6853:   }
6854:   PetscCall(MatSeqAIJRestoreArray(A, &Aa));
6855:   PetscCall(MatSeqAIJRestoreArray(B, &Ba));
6856:   PetscFunctionReturn(PETSC_SUCCESS);
6857: }

6859: /*MC
6860:    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.

6862:    Options Database Keys:
6863: . -mat_type mpiaij - sets the matrix type to `MATMPIAIJ` during a call to `MatSetFromOptions()`

6865:    Level: beginner

6867:    Notes:
6868:    `MatSetValues()` may be called for this matrix type with a `NULL` argument for the numerical values,
6869:     in this case the values associated with the rows and columns one passes in are set to zero
6870:     in the matrix

6872:     `MatSetOptions`(,`MAT_STRUCTURE_ONLY`,`PETSC_TRUE`) may be called for this matrix type. In this no
6873:     space is allocated for the nonzero entries and any entries passed with `MatSetValues()` are ignored

6875: .seealso: [](ch_matrices), `Mat`, `MATSEQAIJ`, `MATAIJ`, `MatCreateAIJ()`
6876: M*/
6877: PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
6878: {
6879:   Mat_MPIAIJ *b;
6880:   PetscMPIInt size;

6882:   PetscFunctionBegin;
6883:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)B), &size));

6885:   PetscCall(PetscNew(&b));
6886:   B->data       = (void *)b;
6887:   B->ops[0]     = MatOps_Values;
6888:   B->assembled  = PETSC_FALSE;
6889:   B->insertmode = NOT_SET_VALUES;
6890:   b->size       = size;

6892:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)B), &b->rank));

6894:   /* build cache for off array entries formed */
6895:   PetscCall(MatStashCreate_Private(PetscObjectComm((PetscObject)B), 1, &B->stash));

6897:   b->donotstash  = PETSC_FALSE;
6898:   b->colmap      = NULL;
6899:   b->garray      = NULL;
6900:   b->roworiented = PETSC_TRUE;

6902:   /* stuff used for matrix vector multiply */
6903:   b->lvec  = NULL;
6904:   b->Mvctx = NULL;

6906:   /* stuff for MatGetRow() */
6907:   b->rowindices   = NULL;
6908:   b->rowvalues    = NULL;
6909:   b->getrowactive = PETSC_FALSE;

6911:   /* flexible pointer used in CUSPARSE classes */
6912:   b->spptr = NULL;

6914:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetUseScalableIncreaseOverlap_C", MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ));
6915:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatStoreValues_C", MatStoreValues_MPIAIJ));
6916:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatRetrieveValues_C", MatRetrieveValues_MPIAIJ));
6917:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatIsTranspose_C", MatIsTranspose_MPIAIJ));
6918:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocation_C", MatMPIAIJSetPreallocation_MPIAIJ));
6919:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetPreallocation_C", MatResetPreallocation_MPIAIJ));
6920:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatResetHash_C", MatResetHash_MPIAIJ));
6921:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatMPIAIJSetPreallocationCSR_C", MatMPIAIJSetPreallocationCSR_MPIAIJ));
6922:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatDiagonalScaleLocal_C", MatDiagonalScaleLocal_MPIAIJ));
6923:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijperm_C", MatConvert_MPIAIJ_MPIAIJPERM));
6924:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijsell_C", MatConvert_MPIAIJ_MPIAIJSELL));
6925: #if defined(PETSC_HAVE_CUDA)
6926:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcusparse_C", MatConvert_MPIAIJ_MPIAIJCUSPARSE));
6927: #endif
6928: #if defined(PETSC_HAVE_HIP)
6929:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijhipsparse_C", MatConvert_MPIAIJ_MPIAIJHIPSPARSE));
6930: #endif
6931: #if defined(PETSC_HAVE_KOKKOS_KERNELS)
6932:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijkokkos_C", MatConvert_MPIAIJ_MPIAIJKokkos));
6933: #endif
6934: #if defined(PETSC_HAVE_MKL_SPARSE)
6935:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijmkl_C", MatConvert_MPIAIJ_MPIAIJMKL));
6936: #endif
6937:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpiaijcrl_C", MatConvert_MPIAIJ_MPIAIJCRL));
6938:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpibaij_C", MatConvert_MPIAIJ_MPIBAIJ));
6939:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisbaij_C", MatConvert_MPIAIJ_MPISBAIJ));
6940:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpidense_C", MatConvert_MPIAIJ_MPIDense));
6941: #if defined(PETSC_HAVE_ELEMENTAL)
6942:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_elemental_C", MatConvert_MPIAIJ_Elemental));
6943: #endif
6944: #if defined(PETSC_HAVE_SCALAPACK)
6945:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_scalapack_C", MatConvert_AIJ_ScaLAPACK));
6946: #endif
6947:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_is_C", MatConvert_XAIJ_IS));
6948:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_mpisell_C", MatConvert_MPIAIJ_MPISELL));
6949: #if defined(PETSC_HAVE_HYPRE)
6950:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatConvert_mpiaij_hypre_C", MatConvert_AIJ_HYPRE));
6951:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_transpose_mpiaij_mpiaij_C", MatProductSetFromOptions_Transpose_AIJ_AIJ));
6952: #endif
6953:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_is_mpiaij_C", MatProductSetFromOptions_IS_XAIJ));
6954:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatProductSetFromOptions_mpiaij_mpiaij_C", MatProductSetFromOptions_MPIAIJ));
6955:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetPreallocationCOO_C", MatSetPreallocationCOO_MPIAIJ));
6956:   PetscCall(PetscObjectComposeFunction((PetscObject)B, "MatSetValuesCOO_C", MatSetValuesCOO_MPIAIJ));
6957:   PetscCall(PetscObjectChangeTypeName((PetscObject)B, MATMPIAIJ));
6958:   PetscFunctionReturn(PETSC_SUCCESS);
6959: }

6961: /*@
6962:   MatCreateMPIAIJWithSplitArrays - creates a `MATMPIAIJ` matrix using arrays that contain the "diagonal"
6963:   and "off-diagonal" part of the matrix in CSR format.

6965:   Collective

6967:   Input Parameters:
6968: + comm - MPI communicator
6969: . m    - number of local rows (Cannot be `PETSC_DECIDE`)
6970: . n    - This value should be the same as the local size used in creating the
6971:          x vector for the matrix-vector product $y = Ax$. (or `PETSC_DECIDE` to have
6972:          calculated if `N` is given) For square matrices `n` is almost always `m`.
6973: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if `m` is given)
6974: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if `n` is given)
6975: . 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
6976: . j    - column indices, which must be local, i.e., based off the start column of the diagonal portion
6977: . a    - matrix values
6978: . 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
6979: . oj   - column indices, which must be global, representing global columns in the `MATMPIAIJ` matrix
6980: - oa   - matrix values

6982:   Output Parameter:
6983: . mat - the matrix

6985:   Level: advanced

6987:   Notes:
6988:   The `i`, `j`, and `a` arrays ARE NOT copied by this routine into the internal format used by PETSc (even in Fortran). The user
6989:   must free the arrays once the matrix has been destroyed and not before.

6991:   The `i` and `j` indices are 0 based

6993:   See `MatCreateAIJ()` for the definition of "diagonal" and "off-diagonal" portion of the matrix

6995:   This sets local rows and cannot be used to set off-processor values.

6997:   Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
6998:   legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
6999:   not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
7000:   the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
7001:   keep track of the underlying array. Use `MatSetOption`(A,`MAT_NO_OFF_PROC_ENTRIES`,`PETSC_TRUE`) to disable all
7002:   communication if it is known that only local entries will be set.

7004: .seealso: [](ch_matrices), `Mat`, `MatCreate()`, `MatCreateSeqAIJ()`, `MatSetValues()`, `MatMPIAIJSetPreallocation()`, `MatMPIAIJSetPreallocationCSR()`,
7005:           `MATMPIAIJ`, `MatCreateAIJ()`, `MatCreateMPIAIJWithArrays()`
7006: @*/
7007: 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)
7008: {
7009:   Mat_MPIAIJ *maij;

7011:   PetscFunctionBegin;
7012:   PetscCheck(m >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "local number of rows (m) cannot be PETSC_DECIDE, or negative");
7013:   PetscCheck(i[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "i (row indices) must start with 0");
7014:   PetscCheck(oi[0] == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "oi (row indices) must start with 0");
7015:   PetscCall(MatCreate(comm, mat));
7016:   PetscCall(MatSetSizes(*mat, m, n, M, N));
7017:   PetscCall(MatSetType(*mat, MATMPIAIJ));
7018:   maij = (Mat_MPIAIJ *)(*mat)->data;

7020:   (*mat)->preallocated = PETSC_TRUE;

7022:   PetscCall(PetscLayoutSetUp((*mat)->rmap));
7023:   PetscCall(PetscLayoutSetUp((*mat)->cmap));

7025:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, n, i, j, a, &maij->A));
7026:   PetscCall(MatCreateSeqAIJWithArrays(PETSC_COMM_SELF, m, (*mat)->cmap->N, oi, oj, oa, &maij->B));

7028:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_TRUE));
7029:   PetscCall(MatAssemblyBegin(*mat, MAT_FINAL_ASSEMBLY));
7030:   PetscCall(MatAssemblyEnd(*mat, MAT_FINAL_ASSEMBLY));
7031:   PetscCall(MatSetOption(*mat, MAT_NO_OFF_PROC_ENTRIES, PETSC_FALSE));
7032:   PetscCall(MatSetOption(*mat, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE));
7033:   PetscFunctionReturn(PETSC_SUCCESS);
7034: }

7036: typedef struct {
7037:   Mat       *mp;    /* intermediate products */
7038:   PetscBool *mptmp; /* is the intermediate product temporary ? */
7039:   PetscInt   cp;    /* number of intermediate products */

7041:   /* support for MatGetBrowsOfAoCols_MPIAIJ for P_oth */
7042:   PetscInt    *startsj_s, *startsj_r;
7043:   PetscScalar *bufa;
7044:   Mat          P_oth;

7046:   /* may take advantage of merging product->B */
7047:   Mat Bloc; /* B-local by merging diag and off-diag */

7049:   /* cusparse does not have support to split between symbolic and numeric phases.
7050:      When api_user is true, we don't need to update the numerical values
7051:      of the temporary storage */
7052:   PetscBool reusesym;

7054:   /* support for COO values insertion */
7055:   PetscScalar *coo_v, *coo_w; /* store on-process and off-process COO scalars, and used as MPI recv/send buffers respectively */
7056:   PetscInt   **own;           /* own[i] points to address of on-process COO indices for Mat mp[i] */
7057:   PetscInt   **off;           /* off[i] points to address of off-process COO indices for Mat mp[i] */
7058:   PetscBool    hasoffproc;    /* if true, have off-process values insertion (i.e. AtB or PtAP) */
7059:   PetscSF      sf;            /* used for non-local values insertion and memory malloc */
7060:   PetscMemType mtype;

7062:   /* customization */
7063:   PetscBool abmerge;
7064:   PetscBool P_oth_bind;
7065: } MatMatMPIAIJBACKEND;

7067: static PetscErrorCode MatDestroy_MatMatMPIAIJBACKEND(void *data)
7068: {
7069:   MatMatMPIAIJBACKEND *mmdata = (MatMatMPIAIJBACKEND *)data;
7070:   PetscInt             i;

7072:   PetscFunctionBegin;
7073:   PetscCall(PetscFree2(mmdata->startsj_s, mmdata->startsj_r));
7074:   PetscCall(PetscFree(mmdata->bufa));
7075:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_v));
7076:   PetscCall(PetscSFFree(mmdata->sf, mmdata->mtype, mmdata->coo_w));
7077:   PetscCall(MatDestroy(&mmdata->P_oth));
7078:   PetscCall(MatDestroy(&mmdata->Bloc));
7079:   PetscCall(PetscSFDestroy(&mmdata->sf));
7080:   for (i = 0; i < mmdata->cp; i++) PetscCall(MatDestroy(&mmdata->mp[i]));
7081:   PetscCall(PetscFree2(mmdata->mp, mmdata->mptmp));
7082:   PetscCall(PetscFree(mmdata->own[0]));
7083:   PetscCall(PetscFree(mmdata->own));
7084:   PetscCall(PetscFree(mmdata->off[0]));
7085:   PetscCall(PetscFree(mmdata->off));
7086:   PetscCall(PetscFree(mmdata));
7087:   PetscFunctionReturn(PETSC_SUCCESS);
7088: }

7090: /* Copy selected n entries with indices in idx[] of A to v[].
7091:    If idx is NULL, copy the whole data array of A to v[]
7092:  */
7093: static PetscErrorCode MatSeqAIJCopySubArray(Mat A, PetscInt n, const PetscInt idx[], PetscScalar v[])
7094: {
7095:   PetscErrorCode (*f)(Mat, PetscInt, const PetscInt[], PetscScalar[]);

7097:   PetscFunctionBegin;
7098:   PetscCall(PetscObjectQueryFunction((PetscObject)A, "MatSeqAIJCopySubArray_C", &f));
7099:   if (f) {
7100:     PetscCall((*f)(A, n, idx, v));
7101:   } else {
7102:     const PetscScalar *vv;

7104:     PetscCall(MatSeqAIJGetArrayRead(A, &vv));
7105:     if (n && idx) {
7106:       PetscScalar    *w  = v;
7107:       const PetscInt *oi = idx;
7108:       PetscInt        j;

7110:       for (j = 0; j < n; j++) *w++ = vv[*oi++];
7111:     } else {
7112:       PetscCall(PetscArraycpy(v, vv, n));
7113:     }
7114:     PetscCall(MatSeqAIJRestoreArrayRead(A, &vv));
7115:   }
7116:   PetscFunctionReturn(PETSC_SUCCESS);
7117: }

7119: static PetscErrorCode MatProductNumeric_MPIAIJBACKEND(Mat C)
7120: {
7121:   MatMatMPIAIJBACKEND *mmdata;
7122:   PetscInt             i, n_d, n_o;

7124:   PetscFunctionBegin;
7125:   MatCheckProduct(C, 1);
7126:   PetscCheck(C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data empty");
7127:   mmdata = (MatMatMPIAIJBACKEND *)C->product->data;
7128:   if (!mmdata->reusesym) { /* update temporary matrices */
7129:     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));
7130:     if (mmdata->Bloc) PetscCall(MatMPIAIJGetLocalMatMerge(C->product->B, MAT_REUSE_MATRIX, NULL, &mmdata->Bloc));
7131:   }
7132:   mmdata->reusesym = PETSC_FALSE;

7134:   for (i = 0; i < mmdata->cp; i++) {
7135:     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]);
7136:     PetscCall((*mmdata->mp[i]->ops->productnumeric)(mmdata->mp[i]));
7137:   }
7138:   for (i = 0, n_d = 0, n_o = 0; i < mmdata->cp; i++) {
7139:     PetscInt noff;

7141:     PetscCall(PetscIntCast(mmdata->off[i + 1] - mmdata->off[i], &noff));
7142:     if (mmdata->mptmp[i]) continue;
7143:     if (noff) {
7144:       PetscInt nown;

7146:       PetscCall(PetscIntCast(mmdata->own[i + 1] - mmdata->own[i], &nown));
7147:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], noff, mmdata->off[i], mmdata->coo_w + n_o));
7148:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], nown, mmdata->own[i], mmdata->coo_v + n_d));
7149:       n_o += noff;
7150:       n_d += nown;
7151:     } else {
7152:       Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mmdata->mp[i]->data;

7154:       PetscCall(MatSeqAIJCopySubArray(mmdata->mp[i], mm->nz, NULL, mmdata->coo_v + n_d));
7155:       n_d += mm->nz;
7156:     }
7157:   }
7158:   if (mmdata->hasoffproc) { /* offprocess insertion */
7159:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7160:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_SCALAR, mmdata->coo_w, mmdata->coo_v + n_d));
7161:   }
7162:   PetscCall(MatSetValuesCOO(C, mmdata->coo_v, INSERT_VALUES));
7163:   PetscFunctionReturn(PETSC_SUCCESS);
7164: }

7166: /* Support for Pt * A, A * P, or Pt * A * P */
7167: #define MAX_NUMBER_INTERMEDIATE 4
7168: PetscErrorCode MatProductSymbolic_MPIAIJBACKEND(Mat C)
7169: {
7170:   Mat_Product           *product = C->product;
7171:   Mat                    A, P, mp[MAX_NUMBER_INTERMEDIATE]; /* A, P and a series of intermediate matrices */
7172:   Mat_MPIAIJ            *a, *p;
7173:   MatMatMPIAIJBACKEND   *mmdata;
7174:   ISLocalToGlobalMapping P_oth_l2g = NULL;
7175:   IS                     glob      = NULL;
7176:   const char            *prefix;
7177:   char                   pprefix[256];
7178:   const PetscInt        *globidx, *P_oth_idx;
7179:   PetscInt               i, j, cp, m, n, M, N, *coo_i, *coo_j;
7180:   PetscCount             ncoo, ncoo_d, ncoo_o, ncoo_oown;
7181:   PetscInt               cmapt[MAX_NUMBER_INTERMEDIATE], rmapt[MAX_NUMBER_INTERMEDIATE]; /* col/row map type for each Mat in mp[]. */
7182:                                                                                          /* type-0: consecutive, start from 0; type-1: consecutive with */
7183:                                                                                          /* a base offset; type-2: sparse with a local to global map table */
7184:   const PetscInt *cmapa[MAX_NUMBER_INTERMEDIATE], *rmapa[MAX_NUMBER_INTERMEDIATE];       /* col/row local to global map array (table) for type-2 map type */

7186:   MatProductType ptype;
7187:   PetscBool      mptmp[MAX_NUMBER_INTERMEDIATE], hasoffproc = PETSC_FALSE, iscuda, iship, iskokk;
7188:   PetscMPIInt    size;

7190:   PetscFunctionBegin;
7191:   MatCheckProduct(C, 1);
7192:   PetscCheck(!product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
7193:   ptype = product->type;
7194:   if (product->A->symmetric == PETSC_BOOL3_TRUE && ptype == MATPRODUCT_AtB) {
7195:     ptype                                          = MATPRODUCT_AB;
7196:     product->symbolic_used_the_fact_A_is_symmetric = PETSC_TRUE;
7197:   }
7198:   switch (ptype) {
7199:   case MATPRODUCT_AB:
7200:     A          = product->A;
7201:     P          = product->B;
7202:     m          = A->rmap->n;
7203:     n          = P->cmap->n;
7204:     M          = A->rmap->N;
7205:     N          = P->cmap->N;
7206:     hasoffproc = PETSC_FALSE; /* will not scatter mat product values to other processes */
7207:     break;
7208:   case MATPRODUCT_AtB:
7209:     P          = product->A;
7210:     A          = product->B;
7211:     m          = P->cmap->n;
7212:     n          = A->cmap->n;
7213:     M          = P->cmap->N;
7214:     N          = A->cmap->N;
7215:     hasoffproc = PETSC_TRUE;
7216:     break;
7217:   case MATPRODUCT_PtAP:
7218:     A          = product->A;
7219:     P          = product->B;
7220:     m          = P->cmap->n;
7221:     n          = P->cmap->n;
7222:     M          = P->cmap->N;
7223:     N          = P->cmap->N;
7224:     hasoffproc = PETSC_TRUE;
7225:     break;
7226:   default:
7227:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7228:   }
7229:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)C), &size));
7230:   if (size == 1) hasoffproc = PETSC_FALSE;

7232:   /* defaults */
7233:   for (i = 0; i < MAX_NUMBER_INTERMEDIATE; i++) {
7234:     mp[i]    = NULL;
7235:     mptmp[i] = PETSC_FALSE;
7236:     rmapt[i] = -1;
7237:     cmapt[i] = -1;
7238:     rmapa[i] = NULL;
7239:     cmapa[i] = NULL;
7240:   }

7242:   /* customization */
7243:   PetscCall(PetscNew(&mmdata));
7244:   mmdata->reusesym = product->api_user;
7245:   if (ptype == MATPRODUCT_AB) {
7246:     if (product->api_user) {
7247:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatMatMult", "Mat");
7248:       PetscCall(PetscOptionsBool("-matmatmult_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7249:       PetscCall(PetscOptionsBool("-matmatmult_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7250:       PetscOptionsEnd();
7251:     } else {
7252:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_AB", "Mat");
7253:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_mergeB", "Merge product->B local matrices", "MatMatMult", mmdata->abmerge, &mmdata->abmerge, NULL));
7254:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7255:       PetscOptionsEnd();
7256:     }
7257:   } else if (ptype == MATPRODUCT_PtAP) {
7258:     if (product->api_user) {
7259:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatPtAP", "Mat");
7260:       PetscCall(PetscOptionsBool("-matptap_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7261:       PetscOptionsEnd();
7262:     } else {
7263:       PetscOptionsBegin(PetscObjectComm((PetscObject)C), ((PetscObject)C)->prefix, "MatProduct_PtAP", "Mat");
7264:       PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_pothbind", "Bind P_oth to CPU", "MatBindToCPU", mmdata->P_oth_bind, &mmdata->P_oth_bind, NULL));
7265:       PetscOptionsEnd();
7266:     }
7267:   }
7268:   a = (Mat_MPIAIJ *)A->data;
7269:   p = (Mat_MPIAIJ *)P->data;
7270:   PetscCall(MatSetSizes(C, m, n, M, N));
7271:   PetscCall(PetscLayoutSetUp(C->rmap));
7272:   PetscCall(PetscLayoutSetUp(C->cmap));
7273:   PetscCall(MatSetType(C, ((PetscObject)A)->type_name));
7274:   PetscCall(MatGetOptionsPrefix(C, &prefix));

7276:   cp = 0;
7277:   switch (ptype) {
7278:   case MATPRODUCT_AB: /* A * P */
7279:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));

7281:     /* A_diag * P_local (merged or not) */
7282:     if (mmdata->abmerge) { /* P's diagonal and off-diag blocks are merged to one matrix, then multiplied by A_diag */
7283:       /* P is product->B */
7284:       PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7285:       PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7286:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7287:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7288:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7289:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7290:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7291:       mp[cp]->product->api_user = product->api_user;
7292:       PetscCall(MatProductSetFromOptions(mp[cp]));
7293:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7294:       PetscCall(ISGetIndices(glob, &globidx));
7295:       rmapt[cp] = 1;
7296:       cmapt[cp] = 2;
7297:       cmapa[cp] = globidx;
7298:       mptmp[cp] = PETSC_FALSE;
7299:       cp++;
7300:     } else { /* A_diag * P_diag and A_diag * P_off */
7301:       PetscCall(MatProductCreate(a->A, p->A, NULL, &mp[cp]));
7302:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7303:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7304:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7305:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7306:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7307:       mp[cp]->product->api_user = product->api_user;
7308:       PetscCall(MatProductSetFromOptions(mp[cp]));
7309:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7310:       rmapt[cp] = 1;
7311:       cmapt[cp] = 1;
7312:       mptmp[cp] = PETSC_FALSE;
7313:       cp++;
7314:       PetscCall(MatProductCreate(a->A, p->B, NULL, &mp[cp]));
7315:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7316:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7317:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7318:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7319:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7320:       mp[cp]->product->api_user = product->api_user;
7321:       PetscCall(MatProductSetFromOptions(mp[cp]));
7322:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7323:       rmapt[cp] = 1;
7324:       cmapt[cp] = 2;
7325:       cmapa[cp] = p->garray;
7326:       mptmp[cp] = PETSC_FALSE;
7327:       cp++;
7328:     }

7330:     /* A_off * P_other */
7331:     if (mmdata->P_oth) {
7332:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g)); /* make P_oth use local col ids */
7333:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7334:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7335:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7336:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7337:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7338:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7339:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7340:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7341:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7342:       mp[cp]->product->api_user = product->api_user;
7343:       PetscCall(MatProductSetFromOptions(mp[cp]));
7344:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7345:       rmapt[cp] = 1;
7346:       cmapt[cp] = 2;
7347:       cmapa[cp] = P_oth_idx;
7348:       mptmp[cp] = PETSC_FALSE;
7349:       cp++;
7350:     }
7351:     break;

7353:   case MATPRODUCT_AtB: /* (P^t * A): P_diag * A_loc + P_off * A_loc */
7354:     /* A is product->B */
7355:     PetscCall(MatMPIAIJGetLocalMatMerge(A, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7356:     if (A == P) { /* when A==P, we can take advantage of the already merged mmdata->Bloc */
7357:       PetscCall(MatProductCreate(mmdata->Bloc, mmdata->Bloc, NULL, &mp[cp]));
7358:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7359:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7360:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7361:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7362:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7363:       mp[cp]->product->api_user = product->api_user;
7364:       PetscCall(MatProductSetFromOptions(mp[cp]));
7365:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7366:       PetscCall(ISGetIndices(glob, &globidx));
7367:       rmapt[cp] = 2;
7368:       rmapa[cp] = globidx;
7369:       cmapt[cp] = 2;
7370:       cmapa[cp] = globidx;
7371:       mptmp[cp] = PETSC_FALSE;
7372:       cp++;
7373:     } else {
7374:       PetscCall(MatProductCreate(p->A, mmdata->Bloc, NULL, &mp[cp]));
7375:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7376:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7377:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7378:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7379:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7380:       mp[cp]->product->api_user = product->api_user;
7381:       PetscCall(MatProductSetFromOptions(mp[cp]));
7382:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7383:       PetscCall(ISGetIndices(glob, &globidx));
7384:       rmapt[cp] = 1;
7385:       cmapt[cp] = 2;
7386:       cmapa[cp] = globidx;
7387:       mptmp[cp] = PETSC_FALSE;
7388:       cp++;
7389:       PetscCall(MatProductCreate(p->B, mmdata->Bloc, NULL, &mp[cp]));
7390:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7391:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7392:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7393:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7394:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7395:       mp[cp]->product->api_user = product->api_user;
7396:       PetscCall(MatProductSetFromOptions(mp[cp]));
7397:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7398:       rmapt[cp] = 2;
7399:       rmapa[cp] = p->garray;
7400:       cmapt[cp] = 2;
7401:       cmapa[cp] = globidx;
7402:       mptmp[cp] = PETSC_FALSE;
7403:       cp++;
7404:     }
7405:     break;
7406:   case MATPRODUCT_PtAP:
7407:     PetscCall(MatGetBrowsOfAoCols_MPIAIJ(A, P, MAT_INITIAL_MATRIX, &mmdata->startsj_s, &mmdata->startsj_r, &mmdata->bufa, &mmdata->P_oth));
7408:     /* P is product->B */
7409:     PetscCall(MatMPIAIJGetLocalMatMerge(P, MAT_INITIAL_MATRIX, &glob, &mmdata->Bloc));
7410:     PetscCall(MatProductCreate(a->A, mmdata->Bloc, NULL, &mp[cp]));
7411:     PetscCall(MatProductSetType(mp[cp], MATPRODUCT_PtAP));
7412:     PetscCall(MatProductSetFill(mp[cp], product->fill));
7413:     PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7414:     PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7415:     PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7416:     mp[cp]->product->api_user = product->api_user;
7417:     PetscCall(MatProductSetFromOptions(mp[cp]));
7418:     PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7419:     PetscCall(ISGetIndices(glob, &globidx));
7420:     rmapt[cp] = 2;
7421:     rmapa[cp] = globidx;
7422:     cmapt[cp] = 2;
7423:     cmapa[cp] = globidx;
7424:     mptmp[cp] = PETSC_FALSE;
7425:     cp++;
7426:     if (mmdata->P_oth) {
7427:       PetscCall(MatSeqAIJCompactOutExtraColumns_SeqAIJ(mmdata->P_oth, &P_oth_l2g));
7428:       PetscCall(ISLocalToGlobalMappingGetIndices(P_oth_l2g, &P_oth_idx));
7429:       PetscCall(MatSetType(mmdata->P_oth, ((PetscObject)a->B)->type_name));
7430:       PetscCall(MatBindToCPU(mmdata->P_oth, mmdata->P_oth_bind));
7431:       PetscCall(MatProductCreate(a->B, mmdata->P_oth, NULL, &mp[cp]));
7432:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AB));
7433:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7434:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7435:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7436:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7437:       mp[cp]->product->api_user = product->api_user;
7438:       PetscCall(MatProductSetFromOptions(mp[cp]));
7439:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7440:       mptmp[cp] = PETSC_TRUE;
7441:       cp++;
7442:       PetscCall(MatProductCreate(mmdata->Bloc, mp[1], NULL, &mp[cp]));
7443:       PetscCall(MatProductSetType(mp[cp], MATPRODUCT_AtB));
7444:       PetscCall(MatProductSetFill(mp[cp], product->fill));
7445:       PetscCall(PetscSNPrintf(pprefix, sizeof(pprefix), "backend_p%" PetscInt_FMT "_", cp));
7446:       PetscCall(MatSetOptionsPrefix(mp[cp], prefix));
7447:       PetscCall(MatAppendOptionsPrefix(mp[cp], pprefix));
7448:       mp[cp]->product->api_user = product->api_user;
7449:       PetscCall(MatProductSetFromOptions(mp[cp]));
7450:       PetscCall((*mp[cp]->ops->productsymbolic)(mp[cp]));
7451:       rmapt[cp] = 2;
7452:       rmapa[cp] = globidx;
7453:       cmapt[cp] = 2;
7454:       cmapa[cp] = P_oth_idx;
7455:       mptmp[cp] = PETSC_FALSE;
7456:       cp++;
7457:     }
7458:     break;
7459:   default:
7460:     SETERRQ(PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[ptype]);
7461:   }
7462:   /* sanity check */
7463:   if (size > 1)
7464:     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);

7466:   PetscCall(PetscMalloc2(cp, &mmdata->mp, cp, &mmdata->mptmp));
7467:   for (i = 0; i < cp; i++) {
7468:     mmdata->mp[i]    = mp[i];
7469:     mmdata->mptmp[i] = mptmp[i];
7470:   }
7471:   mmdata->cp             = cp;
7472:   C->product->data       = mmdata;
7473:   C->product->destroy    = MatDestroy_MatMatMPIAIJBACKEND;
7474:   C->ops->productnumeric = MatProductNumeric_MPIAIJBACKEND;

7476:   /* memory type */
7477:   mmdata->mtype = PETSC_MEMTYPE_HOST;
7478:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iscuda, MATSEQAIJCUSPARSE, MATMPIAIJCUSPARSE, ""));
7479:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iship, MATSEQAIJHIPSPARSE, MATMPIAIJHIPSPARSE, ""));
7480:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &iskokk, MATSEQAIJKOKKOS, MATMPIAIJKOKKOS, ""));
7481:   if (iscuda) mmdata->mtype = PETSC_MEMTYPE_CUDA;
7482:   else if (iship) mmdata->mtype = PETSC_MEMTYPE_HIP;
7483:   else if (iskokk) mmdata->mtype = PETSC_MEMTYPE_KOKKOS;

7485:   /* prepare coo coordinates for values insertion */

7487:   /* count total nonzeros of those intermediate seqaij Mats
7488:     ncoo_d:    # of nonzeros of matrices that do not have offproc entries
7489:     ncoo_o:    # of nonzeros (of matrices that might have offproc entries) that will be inserted to remote procs
7490:     ncoo_oown: # of nonzeros (of matrices that might have offproc entries) that will be inserted locally
7491:   */
7492:   for (cp = 0, ncoo_d = 0, ncoo_o = 0, ncoo_oown = 0; cp < mmdata->cp; cp++) {
7493:     Mat_SeqAIJ *mm = (Mat_SeqAIJ *)mp[cp]->data;
7494:     if (mptmp[cp]) continue;
7495:     if (rmapt[cp] == 2 && hasoffproc) { /* the rows need to be scatter to all processes (might include self) */
7496:       const PetscInt *rmap = rmapa[cp];
7497:       const PetscInt  mr   = mp[cp]->rmap->n;
7498:       const PetscInt  rs   = C->rmap->rstart;
7499:       const PetscInt  re   = C->rmap->rend;
7500:       const PetscInt *ii   = mm->i;
7501:       for (i = 0; i < mr; i++) {
7502:         const PetscInt gr = rmap[i];
7503:         const PetscInt nz = ii[i + 1] - ii[i];
7504:         if (gr < rs || gr >= re) ncoo_o += nz; /* this row is offproc */
7505:         else ncoo_oown += nz;                  /* this row is local */
7506:       }
7507:     } else ncoo_d += mm->nz;
7508:   }

7510:   /*
7511:     ncoo: total number of nonzeros (including those inserted by remote procs) belonging to this proc

7513:     ncoo = ncoo_d + ncoo_oown + ncoo2, which ncoo2 is number of nonzeros inserted to me by other procs.

7515:     off[0] points to a big index array, which is shared by off[1,2,...]. Similarly, for own[0].

7517:     off[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert to others
7518:     own[p]: points to the segment for matrix mp[p], storing location of nonzeros that mp[p] will insert locally
7519:     so, off[p+1]-off[p] is the number of nonzeros that mp[p] will send to others.

7521:     coo_i/j/v[]: [ncoo] row/col/val of nonzeros belonging to this proc.
7522:     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.
7523:   */
7524:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->off)); /* +1 to make a csr-like data structure */
7525:   PetscCall(PetscCalloc1(mmdata->cp + 1, &mmdata->own));

7527:   /* gather (i,j) of nonzeros inserted by remote procs */
7528:   if (hasoffproc) {
7529:     PetscSF  msf;
7530:     PetscInt ncoo2, *coo_i2, *coo_j2;

7532:     PetscCall(PetscMalloc1(ncoo_o, &mmdata->off[0]));
7533:     PetscCall(PetscMalloc1(ncoo_oown, &mmdata->own[0]));
7534:     PetscCall(PetscMalloc2(ncoo_o, &coo_i, ncoo_o, &coo_j)); /* to collect (i,j) of entries to be sent to others */

7536:     for (cp = 0, ncoo_o = 0; cp < mmdata->cp; cp++) {
7537:       Mat_SeqAIJ *mm     = (Mat_SeqAIJ *)mp[cp]->data;
7538:       PetscInt   *idxoff = mmdata->off[cp];
7539:       PetscInt   *idxown = mmdata->own[cp];
7540:       if (!mptmp[cp] && rmapt[cp] == 2) { /* row map is sparse */
7541:         const PetscInt *rmap = rmapa[cp];
7542:         const PetscInt *cmap = cmapa[cp];
7543:         const PetscInt *ii   = mm->i;
7544:         PetscInt       *coi  = coo_i + ncoo_o;
7545:         PetscInt       *coj  = coo_j + ncoo_o;
7546:         const PetscInt  mr   = mp[cp]->rmap->n;
7547:         const PetscInt  rs   = C->rmap->rstart;
7548:         const PetscInt  re   = C->rmap->rend;
7549:         const PetscInt  cs   = C->cmap->rstart;
7550:         for (i = 0; i < mr; i++) {
7551:           const PetscInt *jj = mm->j + ii[i];
7552:           const PetscInt  gr = rmap[i];
7553:           const PetscInt  nz = ii[i + 1] - ii[i];
7554:           if (gr < rs || gr >= re) { /* this is an offproc row */
7555:             for (j = ii[i]; j < ii[i + 1]; j++) {
7556:               *coi++    = gr;
7557:               *idxoff++ = j;
7558:             }
7559:             if (!cmapt[cp]) { /* already global */
7560:               for (j = 0; j < nz; j++) *coj++ = jj[j];
7561:             } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7562:               for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7563:             } else { /* offdiag */
7564:               for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7565:             }
7566:             ncoo_o += nz;
7567:           } else { /* this is a local row */
7568:             for (j = ii[i]; j < ii[i + 1]; j++) *idxown++ = j;
7569:           }
7570:         }
7571:       }
7572:       mmdata->off[cp + 1] = idxoff;
7573:       mmdata->own[cp + 1] = idxown;
7574:     }

7576:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7577:     PetscInt incoo_o;
7578:     PetscCall(PetscIntCast(ncoo_o, &incoo_o));
7579:     PetscCall(PetscSFSetGraphLayout(mmdata->sf, C->rmap, incoo_o /*nleaves*/, NULL /*ilocal*/, PETSC_OWN_POINTER, coo_i));
7580:     PetscCall(PetscSFGetMultiSF(mmdata->sf, &msf));
7581:     PetscCall(PetscSFGetGraph(msf, &ncoo2 /*nroots*/, NULL, NULL, NULL));
7582:     ncoo = ncoo_d + ncoo_oown + ncoo2;
7583:     PetscCall(PetscMalloc2(ncoo, &coo_i2, ncoo, &coo_j2));
7584:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown)); /* put (i,j) of remote nonzeros at back */
7585:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_i, coo_i2 + ncoo_d + ncoo_oown));
7586:     PetscCall(PetscSFGatherBegin(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7587:     PetscCall(PetscSFGatherEnd(mmdata->sf, MPIU_INT, coo_j, coo_j2 + ncoo_d + ncoo_oown));
7588:     PetscCall(PetscFree2(coo_i, coo_j));
7589:     /* allocate MPI send buffer to collect nonzero values to be sent to remote procs */
7590:     PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo_o * sizeof(PetscScalar), (void **)&mmdata->coo_w));
7591:     coo_i = coo_i2;
7592:     coo_j = coo_j2;
7593:   } else { /* no offproc values insertion */
7594:     ncoo = ncoo_d;
7595:     PetscCall(PetscMalloc2(ncoo, &coo_i, ncoo, &coo_j));

7597:     PetscCall(PetscSFCreate(PetscObjectComm((PetscObject)C), &mmdata->sf));
7598:     PetscCall(PetscSFSetGraph(mmdata->sf, 0, 0, NULL, PETSC_OWN_POINTER, NULL, PETSC_OWN_POINTER));
7599:     PetscCall(PetscSFSetUp(mmdata->sf));
7600:   }
7601:   mmdata->hasoffproc = hasoffproc;

7603:   /* gather (i,j) of nonzeros inserted locally */
7604:   for (cp = 0, ncoo_d = 0; cp < mmdata->cp; cp++) {
7605:     Mat_SeqAIJ     *mm   = (Mat_SeqAIJ *)mp[cp]->data;
7606:     PetscInt       *coi  = coo_i + ncoo_d;
7607:     PetscInt       *coj  = coo_j + ncoo_d;
7608:     const PetscInt *jj   = mm->j;
7609:     const PetscInt *ii   = mm->i;
7610:     const PetscInt *cmap = cmapa[cp];
7611:     const PetscInt *rmap = rmapa[cp];
7612:     const PetscInt  mr   = mp[cp]->rmap->n;
7613:     const PetscInt  rs   = C->rmap->rstart;
7614:     const PetscInt  re   = C->rmap->rend;
7615:     const PetscInt  cs   = C->cmap->rstart;

7617:     if (mptmp[cp]) continue;
7618:     if (rmapt[cp] == 1) { /* consecutive rows */
7619:       /* fill coo_i */
7620:       for (i = 0; i < mr; i++) {
7621:         const PetscInt gr = i + rs;
7622:         for (j = ii[i]; j < ii[i + 1]; j++) coi[j] = gr;
7623:       }
7624:       /* fill coo_j */
7625:       if (!cmapt[cp]) { /* type-0, already global */
7626:         PetscCall(PetscArraycpy(coj, jj, mm->nz));
7627:       } else if (cmapt[cp] == 1) {                        /* type-1, local to global for consecutive columns of C */
7628:         for (j = 0; j < mm->nz; j++) coj[j] = jj[j] + cs; /* lid + col start */
7629:       } else {                                            /* type-2, local to global for sparse columns */
7630:         for (j = 0; j < mm->nz; j++) coj[j] = cmap[jj[j]];
7631:       }
7632:       ncoo_d += mm->nz;
7633:     } else if (rmapt[cp] == 2) { /* sparse rows */
7634:       for (i = 0; i < mr; i++) {
7635:         const PetscInt *jj = mm->j + ii[i];
7636:         const PetscInt  gr = rmap[i];
7637:         const PetscInt  nz = ii[i + 1] - ii[i];
7638:         if (gr >= rs && gr < re) { /* local rows */
7639:           for (j = ii[i]; j < ii[i + 1]; j++) *coi++ = gr;
7640:           if (!cmapt[cp]) { /* type-0, already global */
7641:             for (j = 0; j < nz; j++) *coj++ = jj[j];
7642:           } else if (cmapt[cp] == 1) { /* local to global for owned columns of C */
7643:             for (j = 0; j < nz; j++) *coj++ = jj[j] + cs;
7644:           } else { /* type-2, local to global for sparse columns */
7645:             for (j = 0; j < nz; j++) *coj++ = cmap[jj[j]];
7646:           }
7647:           ncoo_d += nz;
7648:         }
7649:       }
7650:     }
7651:   }
7652:   if (glob) PetscCall(ISRestoreIndices(glob, &globidx));
7653:   PetscCall(ISDestroy(&glob));
7654:   if (P_oth_l2g) PetscCall(ISLocalToGlobalMappingRestoreIndices(P_oth_l2g, &P_oth_idx));
7655:   PetscCall(ISLocalToGlobalMappingDestroy(&P_oth_l2g));
7656:   /* allocate an array to store all nonzeros (inserted locally or remotely) belonging to this proc */
7657:   PetscCall(PetscSFMalloc(mmdata->sf, mmdata->mtype, ncoo * sizeof(PetscScalar), (void **)&mmdata->coo_v));

7659:   /* preallocate with COO data */
7660:   PetscCall(MatSetPreallocationCOO(C, ncoo, coo_i, coo_j));
7661:   PetscCall(PetscFree2(coo_i, coo_j));
7662:   PetscFunctionReturn(PETSC_SUCCESS);
7663: }

7665: PetscErrorCode MatProductSetFromOptions_MPIAIJBACKEND(Mat mat)
7666: {
7667:   Mat_Product *product = mat->product;
7668: #if defined(PETSC_HAVE_DEVICE)
7669:   PetscBool match  = PETSC_FALSE;
7670:   PetscBool usecpu = PETSC_FALSE;
7671: #else
7672:   PetscBool match = PETSC_TRUE;
7673: #endif

7675:   PetscFunctionBegin;
7676:   MatCheckProduct(mat, 1);
7677: #if defined(PETSC_HAVE_DEVICE)
7678:   if (!product->A->boundtocpu && !product->B->boundtocpu) PetscCall(PetscObjectTypeCompare((PetscObject)product->B, ((PetscObject)product->A)->type_name, &match));
7679:   if (match) { /* we can always fallback to the CPU if requested */
7680:     switch (product->type) {
7681:     case MATPRODUCT_AB:
7682:       if (product->api_user) {
7683:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatMatMult", "Mat");
7684:         PetscCall(PetscOptionsBool("-matmatmult_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7685:         PetscOptionsEnd();
7686:       } else {
7687:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AB", "Mat");
7688:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatMatMult", usecpu, &usecpu, NULL));
7689:         PetscOptionsEnd();
7690:       }
7691:       break;
7692:     case MATPRODUCT_AtB:
7693:       if (product->api_user) {
7694:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatTransposeMatMult", "Mat");
7695:         PetscCall(PetscOptionsBool("-mattransposematmult_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7696:         PetscOptionsEnd();
7697:       } else {
7698:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_AtB", "Mat");
7699:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatTransposeMatMult", usecpu, &usecpu, NULL));
7700:         PetscOptionsEnd();
7701:       }
7702:       break;
7703:     case MATPRODUCT_PtAP:
7704:       if (product->api_user) {
7705:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatPtAP", "Mat");
7706:         PetscCall(PetscOptionsBool("-matptap_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7707:         PetscOptionsEnd();
7708:       } else {
7709:         PetscOptionsBegin(PetscObjectComm((PetscObject)mat), ((PetscObject)mat)->prefix, "MatProduct_PtAP", "Mat");
7710:         PetscCall(PetscOptionsBool("-mat_product_algorithm_backend_cpu", "Use CPU code", "MatPtAP", usecpu, &usecpu, NULL));
7711:         PetscOptionsEnd();
7712:       }
7713:       break;
7714:     default:
7715:       break;
7716:     }
7717:     match = (PetscBool)!usecpu;
7718:   }
7719: #endif
7720:   if (match) {
7721:     switch (product->type) {
7722:     case MATPRODUCT_AB:
7723:     case MATPRODUCT_AtB:
7724:     case MATPRODUCT_PtAP:
7725:       mat->ops->productsymbolic = MatProductSymbolic_MPIAIJBACKEND;
7726:       break;
7727:     default:
7728:       break;
7729:     }
7730:   }
7731:   /* fallback to MPIAIJ ops */
7732:   if (!mat->ops->productsymbolic) PetscCall(MatProductSetFromOptions_MPIAIJ(mat));
7733:   PetscFunctionReturn(PETSC_SUCCESS);
7734: }

7736: /*
7737:    Produces a set of block column indices of the matrix row, one for each block represented in the original row

7739:    n - the number of block indices in cc[]
7740:    cc - the block indices (must be large enough to contain the indices)
7741: */
7742: static inline PetscErrorCode MatCollapseRow(Mat Amat, PetscInt row, PetscInt bs, PetscInt *n, PetscInt *cc)
7743: {
7744:   PetscInt        cnt = -1, nidx, j;
7745:   const PetscInt *idx;

7747:   PetscFunctionBegin;
7748:   PetscCall(MatGetRow(Amat, row, &nidx, &idx, NULL));
7749:   if (nidx) {
7750:     cnt     = 0;
7751:     cc[cnt] = idx[0] / bs;
7752:     for (j = 1; j < nidx; j++) {
7753:       if (cc[cnt] < idx[j] / bs) cc[++cnt] = idx[j] / bs;
7754:     }
7755:   }
7756:   PetscCall(MatRestoreRow(Amat, row, &nidx, &idx, NULL));
7757:   *n = cnt + 1;
7758:   PetscFunctionReturn(PETSC_SUCCESS);
7759: }

7761: /*
7762:     Produces a set of block column indices of the matrix block row, one for each block represented in the original set of rows

7764:     ncollapsed - the number of block indices
7765:     collapsed - the block indices (must be large enough to contain the indices)
7766: */
7767: static inline PetscErrorCode MatCollapseRows(Mat Amat, PetscInt start, PetscInt bs, PetscInt *w0, PetscInt *w1, PetscInt *w2, PetscInt *ncollapsed, PetscInt **collapsed)
7768: {
7769:   PetscInt i, nprev, *cprev = w0, ncur = 0, *ccur = w1, *merged = w2, *cprevtmp;

7771:   PetscFunctionBegin;
7772:   PetscCall(MatCollapseRow(Amat, start, bs, &nprev, cprev));
7773:   for (i = start + 1; i < start + bs; i++) {
7774:     PetscCall(MatCollapseRow(Amat, i, bs, &ncur, ccur));
7775:     PetscCall(PetscMergeIntArray(nprev, cprev, ncur, ccur, &nprev, &merged));
7776:     cprevtmp = cprev;
7777:     cprev    = merged;
7778:     merged   = cprevtmp;
7779:   }
7780:   *ncollapsed = nprev;
7781:   if (collapsed) *collapsed = cprev;
7782:   PetscFunctionReturn(PETSC_SUCCESS);
7783: }

7785: /*
7786:  MatCreateGraph_Simple_AIJ - create simple scalar matrix (graph) from potentially blocked matrix

7788:  Input Parameter:
7789:  . Amat - matrix
7790:  - symmetrize - make the result symmetric
7791:  + scale - scale with diagonal

7793:  Output Parameter:
7794:  . a_Gmat - output scalar graph >= 0

7796: */
7797: PETSC_INTERN PetscErrorCode MatCreateGraph_Simple_AIJ(Mat Amat, PetscBool symmetrize, PetscBool scale, PetscReal filter, PetscInt index_size, PetscInt index[], Mat *a_Gmat)
7798: {
7799:   PetscInt  Istart, Iend, Ii, jj, kk, ncols, nloc, NN, MM, bs;
7800:   MPI_Comm  comm;
7801:   Mat       Gmat;
7802:   PetscBool ismpiaij, isseqaij;
7803:   Mat       a, b, c;
7804:   MatType   jtype;

7806:   PetscFunctionBegin;
7807:   PetscCall(PetscObjectGetComm((PetscObject)Amat, &comm));
7808:   PetscCall(MatGetOwnershipRange(Amat, &Istart, &Iend));
7809:   PetscCall(MatGetSize(Amat, &MM, &NN));
7810:   PetscCall(MatGetBlockSize(Amat, &bs));
7811:   nloc = (Iend - Istart) / bs;

7813:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATSEQAIJ, &isseqaij));
7814:   PetscCall(PetscObjectBaseTypeCompare((PetscObject)Amat, MATMPIAIJ, &ismpiaij));
7815:   PetscCheck(isseqaij || ismpiaij, comm, PETSC_ERR_USER, "Require (MPI)AIJ matrix type");

7817:   /* TODO GPU: these calls are potentially expensive if matrices are large and we want to use the GPU */
7818:   /* A solution consists in providing a new API, MatAIJGetCollapsedAIJ, and each class can provide a fast
7819:      implementation */
7820:   if (bs > 1) {
7821:     PetscCall(MatGetType(Amat, &jtype));
7822:     PetscCall(MatCreate(comm, &Gmat));
7823:     PetscCall(MatSetType(Gmat, jtype));
7824:     PetscCall(MatSetSizes(Gmat, nloc, nloc, PETSC_DETERMINE, PETSC_DETERMINE));
7825:     PetscCall(MatSetBlockSizes(Gmat, 1, 1));
7826:     if (isseqaij || ((Mat_MPIAIJ *)Amat->data)->garray) {
7827:       PetscInt  *d_nnz, *o_nnz;
7828:       MatScalar *aa, val, *AA;
7829:       PetscInt  *aj, *ai, *AJ, nc, nmax = 0;

7831:       if (isseqaij) {
7832:         a = Amat;
7833:         b = NULL;
7834:       } else {
7835:         Mat_MPIAIJ *d = (Mat_MPIAIJ *)Amat->data;
7836:         a             = d->A;
7837:         b             = d->B;
7838:       }
7839:       PetscCall(PetscInfo(Amat, "New bs>1 Graph. nloc=%" PetscInt_FMT "\n", nloc));
7840:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7841:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
7842:         PetscInt       *nnz = (c == a) ? d_nnz : o_nnz;
7843:         const PetscInt *cols1, *cols2;

7845:         for (PetscInt brow = 0, nc1, nc2, ok = 1; brow < nloc * bs; brow += bs) { // block rows
7846:           PetscCall(MatGetRow(c, brow, &nc2, &cols2, NULL));
7847:           nnz[brow / bs] = nc2 / bs;
7848:           if (nc2 % bs) ok = 0;
7849:           if (nnz[brow / bs] > nmax) nmax = nnz[brow / bs];
7850:           for (PetscInt ii = 1; ii < bs; ii++) { // check for non-dense blocks
7851:             PetscCall(MatGetRow(c, brow + ii, &nc1, &cols1, NULL));
7852:             if (nc1 != nc2) ok = 0;
7853:             else {
7854:               for (PetscInt jj = 0; jj < nc1 && ok == 1; jj++) {
7855:                 if (cols1[jj] != cols2[jj]) ok = 0;
7856:                 if (cols1[jj] % bs != jj % bs) ok = 0;
7857:               }
7858:             }
7859:             PetscCall(MatRestoreRow(c, brow + ii, &nc1, &cols1, NULL));
7860:           }
7861:           PetscCall(MatRestoreRow(c, brow, &nc2, &cols2, NULL));
7862:           if (!ok) {
7863:             PetscCall(PetscFree2(d_nnz, o_nnz));
7864:             PetscCall(PetscInfo(Amat, "Found sparse blocks - revert to slow method\n"));
7865:             goto old_bs;
7866:           }
7867:         }
7868:       }
7869:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
7870:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
7871:       PetscCall(PetscFree2(d_nnz, o_nnz));
7872:       PetscCall(PetscMalloc2(nmax, &AA, nmax, &AJ));
7873:       // diag
7874:       for (PetscInt brow = 0, n, grow; brow < nloc * bs; brow += bs) { // block rows
7875:         Mat_SeqAIJ *aseq = (Mat_SeqAIJ *)a->data;

7877:         ai = aseq->i;
7878:         n  = ai[brow + 1] - ai[brow];
7879:         aj = aseq->j + ai[brow];
7880:         for (PetscInt k = 0; k < n; k += bs) {   // block columns
7881:           AJ[k / bs] = aj[k] / bs + Istart / bs; // diag starts at (Istart,Istart)
7882:           val        = 0;
7883:           if (index_size == 0) {
7884:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7885:               aa = aseq->a + ai[brow + ii] + k;
7886:               for (PetscInt jj = 0; jj < bs; jj++) {    // columns in block
7887:                 val += PetscAbs(PetscRealPart(aa[jj])); // a sort of norm
7888:               }
7889:             }
7890:           } else {                                            // use (index,index) value if provided
7891:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7892:               PetscInt ii = index[iii];
7893:               aa          = aseq->a + ai[brow + ii] + k;
7894:               for (PetscInt jjj = 0; jjj < index_size; jjj++) { // columns in block
7895:                 PetscInt jj = index[jjj];
7896:                 val += PetscAbs(PetscRealPart(aa[jj]));
7897:               }
7898:             }
7899:           }
7900:           PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7901:           AA[k / bs] = val;
7902:         }
7903:         grow = Istart / bs + brow / bs;
7904:         PetscCall(MatSetValues(Gmat, 1, &grow, n / bs, AJ, AA, ADD_VALUES));
7905:       }
7906:       // off-diag
7907:       if (ismpiaij) {
7908:         Mat_MPIAIJ        *aij = (Mat_MPIAIJ *)Amat->data;
7909:         const PetscScalar *vals;
7910:         const PetscInt    *cols, *garray = aij->garray;

7912:         PetscCheck(garray, PETSC_COMM_SELF, PETSC_ERR_USER, "No garray ?");
7913:         for (PetscInt brow = 0, grow; brow < nloc * bs; brow += bs) { // block rows
7914:           PetscCall(MatGetRow(b, brow, &ncols, &cols, NULL));
7915:           for (PetscInt k = 0, cidx = 0; k < ncols; k += bs, cidx++) {
7916:             PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs >= nmax");
7917:             AA[k / bs] = 0;
7918:             AJ[cidx]   = garray[cols[k]] / bs;
7919:           }
7920:           nc = ncols / bs;
7921:           PetscCall(MatRestoreRow(b, brow, &ncols, &cols, NULL));
7922:           if (index_size == 0) {
7923:             for (PetscInt ii = 0; ii < bs; ii++) { // rows in block
7924:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7925:               for (PetscInt k = 0; k < ncols; k += bs) {
7926:                 for (PetscInt jj = 0; jj < bs; jj++) { // cols in block
7927:                   PetscAssert(k / bs < nmax, comm, PETSC_ERR_USER, "k / bs (%" PetscInt_FMT ") >= nmax (%" PetscInt_FMT ")", k / bs, nmax);
7928:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7929:                 }
7930:               }
7931:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7932:             }
7933:           } else {                                            // use (index,index) value if provided
7934:             for (PetscInt iii = 0; iii < index_size; iii++) { // rows in block
7935:               PetscInt ii = index[iii];
7936:               PetscCall(MatGetRow(b, brow + ii, &ncols, &cols, &vals));
7937:               for (PetscInt k = 0; k < ncols; k += bs) {
7938:                 for (PetscInt jjj = 0; jjj < index_size; jjj++) { // cols in block
7939:                   PetscInt jj = index[jjj];
7940:                   AA[k / bs] += PetscAbs(PetscRealPart(vals[k + jj]));
7941:                 }
7942:               }
7943:               PetscCall(MatRestoreRow(b, brow + ii, &ncols, &cols, &vals));
7944:             }
7945:           }
7946:           grow = Istart / bs + brow / bs;
7947:           PetscCall(MatSetValues(Gmat, 1, &grow, nc, AJ, AA, ADD_VALUES));
7948:         }
7949:       }
7950:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
7951:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
7952:       PetscCall(PetscFree2(AA, AJ));
7953:     } else {
7954:       const PetscScalar *vals;
7955:       const PetscInt    *idx;
7956:       PetscInt          *d_nnz, *o_nnz, *w0, *w1, *w2;
7957:     old_bs:
7958:       /*
7959:        Determine the preallocation needed for the scalar matrix derived from the vector matrix.
7960:        */
7961:       PetscCall(PetscInfo(Amat, "OLD bs>1 CreateGraph\n"));
7962:       PetscCall(PetscMalloc2(nloc, &d_nnz, (isseqaij ? 0 : nloc), &o_nnz));
7963:       if (isseqaij) {
7964:         PetscInt max_d_nnz;

7966:         /*
7967:          Determine exact preallocation count for (sequential) scalar matrix
7968:          */
7969:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Amat, &max_d_nnz));
7970:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7971:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7972:         for (Ii = 0, jj = 0; Ii < Iend; Ii += bs, jj++) PetscCall(MatCollapseRows(Amat, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7973:         PetscCall(PetscFree3(w0, w1, w2));
7974:       } else if (ismpiaij) {
7975:         Mat             Daij, Oaij;
7976:         const PetscInt *garray;
7977:         PetscInt        max_d_nnz;

7979:         PetscCall(MatMPIAIJGetSeqAIJ(Amat, &Daij, &Oaij, &garray));
7980:         /*
7981:          Determine exact preallocation count for diagonal block portion of scalar matrix
7982:          */
7983:         PetscCall(MatSeqAIJGetMaxRowNonzeros(Daij, &max_d_nnz));
7984:         max_d_nnz = PetscMin(nloc, bs * max_d_nnz);
7985:         PetscCall(PetscMalloc3(max_d_nnz, &w0, max_d_nnz, &w1, max_d_nnz, &w2));
7986:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) PetscCall(MatCollapseRows(Daij, Ii, bs, w0, w1, w2, &d_nnz[jj], NULL));
7987:         PetscCall(PetscFree3(w0, w1, w2));
7988:         /*
7989:          Over estimate (usually grossly over), preallocation count for off-diagonal portion of scalar matrix
7990:          */
7991:         for (Ii = 0, jj = 0; Ii < Iend - Istart; Ii += bs, jj++) {
7992:           o_nnz[jj] = 0;
7993:           for (kk = 0; kk < bs; kk++) { /* rows that get collapsed to a single row */
7994:             PetscCall(MatGetRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7995:             o_nnz[jj] += ncols;
7996:             PetscCall(MatRestoreRow(Oaij, Ii + kk, &ncols, NULL, NULL));
7997:           }
7998:           if (o_nnz[jj] > (NN / bs - nloc)) o_nnz[jj] = NN / bs - nloc;
7999:         }
8000:       } else SETERRQ(comm, PETSC_ERR_USER, "Require AIJ matrix type");
8001:       /* get scalar copy (norms) of matrix */
8002:       PetscCall(MatSeqAIJSetPreallocation(Gmat, 0, d_nnz));
8003:       PetscCall(MatMPIAIJSetPreallocation(Gmat, 0, d_nnz, 0, o_nnz));
8004:       PetscCall(PetscFree2(d_nnz, o_nnz));
8005:       for (Ii = Istart; Ii < Iend; Ii++) {
8006:         PetscInt dest_row = Ii / bs;

8008:         PetscCall(MatGetRow(Amat, Ii, &ncols, &idx, &vals));
8009:         for (jj = 0; jj < ncols; jj++) {
8010:           PetscInt    dest_col = idx[jj] / bs;
8011:           PetscScalar sv       = PetscAbs(PetscRealPart(vals[jj]));

8013:           PetscCall(MatSetValues(Gmat, 1, &dest_row, 1, &dest_col, &sv, ADD_VALUES));
8014:         }
8015:         PetscCall(MatRestoreRow(Amat, Ii, &ncols, &idx, &vals));
8016:       }
8017:       PetscCall(MatAssemblyBegin(Gmat, MAT_FINAL_ASSEMBLY));
8018:       PetscCall(MatAssemblyEnd(Gmat, MAT_FINAL_ASSEMBLY));
8019:     }
8020:   } else {
8021:     if (symmetrize || filter >= 0 || scale) PetscCall(MatDuplicate(Amat, MAT_COPY_VALUES, &Gmat));
8022:     else {
8023:       Gmat = Amat;
8024:       PetscCall(PetscObjectReference((PetscObject)Gmat));
8025:     }
8026:     if (isseqaij) {
8027:       a = Gmat;
8028:       b = NULL;
8029:     } else {
8030:       Mat_MPIAIJ *d = (Mat_MPIAIJ *)Gmat->data;
8031:       a             = d->A;
8032:       b             = d->B;
8033:     }
8034:     if (filter >= 0 || scale) {
8035:       /* take absolute value of each entry */
8036:       for (c = a, kk = 0; c && kk < 2; c = b, kk++) {
8037:         MatInfo      info;
8038:         PetscScalar *avals;

8040:         PetscCall(MatGetInfo(c, MAT_LOCAL, &info));
8041:         PetscCall(MatSeqAIJGetArray(c, &avals));
8042:         for (int jj = 0; jj < info.nz_used; jj++) avals[jj] = PetscAbsScalar(avals[jj]);
8043:         PetscCall(MatSeqAIJRestoreArray(c, &avals));
8044:       }
8045:     }
8046:   }
8047:   if (symmetrize) {
8048:     PetscBool isset, issym;

8050:     PetscCall(MatIsSymmetricKnown(Amat, &isset, &issym));
8051:     if (!isset || !issym) {
8052:       Mat matTrans;

8054:       PetscCall(MatTranspose(Gmat, MAT_INITIAL_MATRIX, &matTrans));
8055:       PetscCall(MatAXPY(Gmat, 1.0, matTrans, Gmat->structurally_symmetric == PETSC_BOOL3_TRUE ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN));
8056:       PetscCall(MatDestroy(&matTrans));
8057:     }
8058:     PetscCall(MatSetOption(Gmat, MAT_SYMMETRIC, PETSC_TRUE));
8059:   } else if (Amat != Gmat) PetscCall(MatPropagateSymmetryOptions(Amat, Gmat));
8060:   if (scale) {
8061:     /* scale c for all diagonal values = 1 or -1 */
8062:     Vec diag;

8064:     PetscCall(MatCreateVecs(Gmat, &diag, NULL));
8065:     PetscCall(MatGetDiagonal(Gmat, diag));
8066:     PetscCall(VecReciprocal(diag));
8067:     PetscCall(VecSqrtAbs(diag));
8068:     PetscCall(MatDiagonalScale(Gmat, diag, diag));
8069:     PetscCall(VecDestroy(&diag));
8070:   }
8071:   PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_graph_view"));
8072:   if (filter >= 0) {
8073:     PetscCall(MatFilter(Gmat, filter, PETSC_TRUE, PETSC_TRUE));
8074:     PetscCall(MatViewFromOptions(Gmat, NULL, "-mat_filter_graph_view"));
8075:   }
8076:   *a_Gmat = Gmat;
8077:   PetscFunctionReturn(PETSC_SUCCESS);
8078: }

8080: /*
8081:     Special version for direct calls from Fortran
8082: */

8084: /* Change these macros so can be used in void function */
8085: /* Identical to PetscCallVoid, except it assigns to *_ierr */
8086: #undef PetscCall
8087: #define PetscCall(...) \
8088:   do { \
8089:     PetscErrorCode ierr_msv_mpiaij = __VA_ARGS__; \
8090:     if (PetscUnlikely(ierr_msv_mpiaij)) { \
8091:       *_ierr = PetscError(PETSC_COMM_SELF, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr_msv_mpiaij, PETSC_ERROR_REPEAT, " "); \
8092:       return; \
8093:     } \
8094:   } while (0)

8096: #undef SETERRQ
8097: #define SETERRQ(comm, ierr, ...) \
8098:   do { \
8099:     *_ierr = PetscError(comm, __LINE__, PETSC_FUNCTION_NAME, __FILE__, ierr, PETSC_ERROR_INITIAL, __VA_ARGS__); \
8100:     return; \
8101:   } while (0)

8103: #if defined(PETSC_HAVE_FORTRAN_CAPS)
8104:   #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
8105: #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
8106:   #define matsetvaluesmpiaij_ matsetvaluesmpiaij
8107: #else
8108: #endif
8109: PETSC_EXTERN void matsetvaluesmpiaij_(Mat *mmat, PetscInt *mm, const PetscInt im[], PetscInt *mn, const PetscInt in[], const PetscScalar v[], InsertMode *maddv, PetscErrorCode *_ierr)
8110: {
8111:   Mat         mat = *mmat;
8112:   PetscInt    m = *mm, n = *mn;
8113:   InsertMode  addv = *maddv;
8114:   Mat_MPIAIJ *aij  = (Mat_MPIAIJ *)mat->data;
8115:   PetscScalar value;

8117:   MatCheckPreallocated(mat, 1);
8118:   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
8119:   else PetscCheck(mat->insertmode == addv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Cannot mix add values and insert values");
8120:   {
8121:     PetscInt  i, j, rstart = mat->rmap->rstart, rend = mat->rmap->rend;
8122:     PetscInt  cstart = mat->cmap->rstart, cend = mat->cmap->rend, row, col;
8123:     PetscBool roworiented = aij->roworiented;

8125:     /* Some Variables required in the macro */
8126:     Mat         A     = aij->A;
8127:     Mat_SeqAIJ *a     = (Mat_SeqAIJ *)A->data;
8128:     PetscInt   *aimax = a->imax, *ai = a->i, *ailen = a->ilen, *aj = a->j;
8129:     MatScalar  *aa;
8130:     PetscBool   ignorezeroentries = ((a->ignorezeroentries && (addv == ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
8131:     Mat         B                 = aij->B;
8132:     Mat_SeqAIJ *b                 = (Mat_SeqAIJ *)B->data;
8133:     PetscInt   *bimax = b->imax, *bi = b->i, *bilen = b->ilen, *bj = b->j, bm = aij->B->rmap->n, am = aij->A->rmap->n;
8134:     MatScalar  *ba;
8135:     /* This variable below is only for the PETSC_HAVE_VIENNACL or PETSC_HAVE_CUDA cases, but we define it in all cases because we
8136:      * cannot use "#if defined" inside a macro. */
8137:     PETSC_UNUSED PetscBool inserted = PETSC_FALSE;

8139:     PetscInt  *rp1, *rp2, ii, nrow1, nrow2, _i, rmax1, rmax2, N, low1, high1, low2, high2, t, lastcol1, lastcol2;
8140:     PetscInt   nonew = a->nonew;
8141:     MatScalar *ap1, *ap2;

8143:     PetscFunctionBegin;
8144:     PetscCall(MatSeqAIJGetArray(A, &aa));
8145:     PetscCall(MatSeqAIJGetArray(B, &ba));
8146:     for (i = 0; i < m; i++) {
8147:       if (im[i] < 0) continue;
8148:       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);
8149:       if (im[i] >= rstart && im[i] < rend) {
8150:         row      = im[i] - rstart;
8151:         lastcol1 = -1;
8152:         rp1      = aj + ai[row];
8153:         ap1      = aa + ai[row];
8154:         rmax1    = aimax[row];
8155:         nrow1    = ailen[row];
8156:         low1     = 0;
8157:         high1    = nrow1;
8158:         lastcol2 = -1;
8159:         rp2      = bj + bi[row];
8160:         ap2      = ba + bi[row];
8161:         rmax2    = bimax[row];
8162:         nrow2    = bilen[row];
8163:         low2     = 0;
8164:         high2    = nrow2;

8166:         for (j = 0; j < n; j++) {
8167:           if (roworiented) value = v[i * n + j];
8168:           else value = v[i + j * m];
8169:           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES) && im[i] != in[j]) continue;
8170:           if (in[j] >= cstart && in[j] < cend) {
8171:             col = in[j] - cstart;
8172:             MatSetValues_SeqAIJ_A_Private(row, col, value, addv, im[i], in[j]);
8173:           } else if (in[j] < 0) continue;
8174:           else if (PetscUnlikelyDebug(in[j] >= mat->cmap->N)) {
8175:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Column too large: col %" PetscInt_FMT " max %" PetscInt_FMT, in[j], mat->cmap->N - 1);
8176:           } else {
8177:             if (mat->was_assembled) {
8178:               if (!aij->colmap) PetscCall(MatCreateColmap_MPIAIJ_Private(mat));
8179: #if defined(PETSC_USE_CTABLE)
8180:               PetscCall(PetscHMapIGetWithDefault(aij->colmap, in[j] + 1, 0, &col));
8181:               col--;
8182: #else
8183:               col = aij->colmap[in[j]] - 1;
8184: #endif
8185:               if (col < 0 && !((Mat_SeqAIJ *)aij->A->data)->nonew) {
8186:                 PetscCall(MatDisAssemble_MPIAIJ(mat));
8187:                 col = in[j];
8188:                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
8189:                 B        = aij->B;
8190:                 b        = (Mat_SeqAIJ *)B->data;
8191:                 bimax    = b->imax;
8192:                 bi       = b->i;
8193:                 bilen    = b->ilen;
8194:                 bj       = b->j;
8195:                 rp2      = bj + bi[row];
8196:                 ap2      = ba + bi[row];
8197:                 rmax2    = bimax[row];
8198:                 nrow2    = bilen[row];
8199:                 low2     = 0;
8200:                 high2    = nrow2;
8201:                 bm       = aij->B->rmap->n;
8202:                 ba       = b->a;
8203:                 inserted = PETSC_FALSE;
8204:               }
8205:             } else col = in[j];
8206:             MatSetValues_SeqAIJ_B_Private(row, col, value, addv, im[i], in[j]);
8207:           }
8208:         }
8209:       } else if (!aij->donotstash) {
8210:         if (roworiented) {
8211:           PetscCall(MatStashValuesRow_Private(&mat->stash, im[i], n, in, v + i * n, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8212:         } else {
8213:           PetscCall(MatStashValuesCol_Private(&mat->stash, im[i], n, in, v + i, m, (PetscBool)(ignorezeroentries && (addv == ADD_VALUES))));
8214:         }
8215:       }
8216:     }
8217:     PetscCall(MatSeqAIJRestoreArray(A, &aa));
8218:     PetscCall(MatSeqAIJRestoreArray(B, &ba));
8219:   }
8220:   PetscFunctionReturnVoid();
8221: }

8223: /* Undefining these here since they were redefined from their original definition above! No
8224:  * other PETSc functions should be defined past this point, as it is impossible to recover the
8225:  * original definitions */
8226: #undef PetscCall
8227: #undef SETERRQ