Actual source code: cdiagonal.c

  1: #include <petsc/private/matimpl.h>

  3: typedef struct {
  4:   PetscScalar diag;
  5: } Mat_ConstantDiagonal;

  7: static PetscErrorCode MatAXPY_ConstantDiagonal(Mat Y, PetscScalar a, Mat X, MatStructure str)
  8: {
  9:   Mat_ConstantDiagonal *yctx = (Mat_ConstantDiagonal *)Y->data;
 10:   Mat_ConstantDiagonal *xctx = (Mat_ConstantDiagonal *)X->data;

 12:   PetscFunctionBegin;
 13:   yctx->diag += a * xctx->diag;
 14:   PetscFunctionReturn(PETSC_SUCCESS);
 15: }

 17: static PetscErrorCode MatEqual_ConstantDiagonal(Mat Y, Mat X, PetscBool *equal)
 18: {
 19:   Mat_ConstantDiagonal *yctx = (Mat_ConstantDiagonal *)Y->data;
 20:   Mat_ConstantDiagonal *xctx = (Mat_ConstantDiagonal *)X->data;

 22:   PetscFunctionBegin;
 23:   *equal = (yctx->diag == xctx->diag) ? PETSC_TRUE : PETSC_FALSE;
 24:   PetscFunctionReturn(PETSC_SUCCESS);
 25: }

 27: static PetscErrorCode MatGetRow_ConstantDiagonal(Mat A, PetscInt row, PetscInt *ncols, PetscInt *cols[], PetscScalar *vals[])
 28: {
 29:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)A->data;

 31:   PetscFunctionBegin;
 32:   if (ncols) *ncols = 1;
 33:   if (cols) {
 34:     PetscCall(PetscMalloc1(1, cols));
 35:     (*cols)[0] = row;
 36:   }
 37:   if (vals) {
 38:     PetscCall(PetscMalloc1(1, vals));
 39:     (*vals)[0] = ctx->diag;
 40:   }
 41:   PetscFunctionReturn(PETSC_SUCCESS);
 42: }

 44: static PetscErrorCode MatRestoreRow_ConstantDiagonal(Mat A, PetscInt row, PetscInt *ncols, PetscInt *cols[], PetscScalar *vals[])
 45: {
 46:   PetscFunctionBegin;
 47:   if (cols) PetscCall(PetscFree(*cols));
 48:   if (vals) PetscCall(PetscFree(*vals));
 49:   PetscFunctionReturn(PETSC_SUCCESS);
 50: }

 52: static PetscErrorCode MatMultAdd_ConstantDiagonal(Mat mat, Vec v1, Vec v2, Vec v3)
 53: {
 54:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)mat->data;

 56:   PetscFunctionBegin;
 57:   if (v2 == v3) PetscCall(VecAXPBY(v3, ctx->diag, 1.0, v1));
 58:   else PetscCall(VecAXPBYPCZ(v3, ctx->diag, 1.0, 0.0, v1, v2));
 59:   PetscFunctionReturn(PETSC_SUCCESS);
 60: }

 62: static PetscErrorCode MatMultHermitianTransposeAdd_ConstantDiagonal(Mat mat, Vec v1, Vec v2, Vec v3)
 63: {
 64:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)mat->data;

 66:   PetscFunctionBegin;
 67:   if (v2 == v3) PetscCall(VecAXPBY(v3, PetscConj(ctx->diag), 1.0, v1));
 68:   else PetscCall(VecAXPBYPCZ(v3, PetscConj(ctx->diag), 1.0, 0.0, v1, v2));
 69:   PetscFunctionReturn(PETSC_SUCCESS);
 70: }

 72: static PetscErrorCode MatNorm_ConstantDiagonal(Mat A, NormType type, PetscReal *nrm)
 73: {
 74:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)A->data;

 76:   PetscFunctionBegin;
 77:   PetscCheck(type == NORM_FROBENIUS || type == NORM_2 || type == NORM_1 || type == NORM_INFINITY, PetscObjectComm((PetscObject)A), PETSC_ERR_SUP, "Unsupported norm");
 78:   *nrm = PetscAbsScalar(ctx->diag);
 79:   PetscFunctionReturn(PETSC_SUCCESS);
 80: }

 82: static PetscErrorCode MatCreateSubMatrices_ConstantDiagonal(Mat A, PetscInt n, const IS irow[], const IS icol[], MatReuse scall, Mat *submat[])
 83: {
 84:   Mat B;

 86:   PetscFunctionBegin;
 87:   PetscCall(MatConvert(A, MATAIJ, MAT_INITIAL_MATRIX, &B));
 88:   PetscCall(MatCreateSubMatrices(B, n, irow, icol, scall, submat));
 89:   PetscCall(MatDestroy(&B));
 90:   PetscFunctionReturn(PETSC_SUCCESS);
 91: }

 93: static PetscErrorCode MatDuplicate_ConstantDiagonal(Mat A, MatDuplicateOption op, Mat *B)
 94: {
 95:   Mat_ConstantDiagonal *actx = (Mat_ConstantDiagonal *)A->data;

 97:   PetscFunctionBegin;
 98:   PetscCall(MatCreate(PetscObjectComm((PetscObject)A), B));
 99:   PetscCall(MatSetSizes(*B, A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N));
100:   PetscCall(MatSetBlockSizesFromMats(*B, A, A));
101:   PetscCall(MatSetType(*B, MATCONSTANTDIAGONAL));
102:   PetscCall(PetscLayoutReference(A->rmap, &(*B)->rmap));
103:   PetscCall(PetscLayoutReference(A->cmap, &(*B)->cmap));
104:   if (op == MAT_COPY_VALUES) {
105:     Mat_ConstantDiagonal *bctx = (Mat_ConstantDiagonal *)(*B)->data;
106:     bctx->diag                 = actx->diag;
107:   }
108:   PetscFunctionReturn(PETSC_SUCCESS);
109: }

111: static PetscErrorCode MatDestroy_ConstantDiagonal(Mat mat)
112: {
113:   PetscFunctionBegin;
114:   PetscCall(PetscFree(mat->data));
115:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatConstantDiagonalGetConstant_C", NULL));
116:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_constantdiagonal_constantdiagonal_C", NULL));
117:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_constantdiagonal_diagonal_C", NULL));
118:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_diagonal_constantdiagonal_C", NULL));
119:   PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatProductSetFromOptions_anytype_C", NULL));
120:   PetscFunctionReturn(PETSC_SUCCESS);
121: }

123: static PetscErrorCode MatView_ConstantDiagonal(Mat J, PetscViewer viewer)
124: {
125:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)J->data;
126:   PetscBool             isascii;

128:   PetscFunctionBegin;
129:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
130:   if (isascii) {
131:     PetscViewerFormat format;

133:     PetscCall(PetscViewerGetFormat(viewer, &format));
134:     if (format == PETSC_VIEWER_ASCII_FACTOR_INFO || format == PETSC_VIEWER_ASCII_INFO) PetscFunctionReturn(PETSC_SUCCESS);
135:     if (PetscImaginaryPart(ctx->diag) == 0) {
136:       PetscCall(PetscViewerASCIIPrintf(viewer, "Diagonal value: %g\n", (double)PetscRealPart(ctx->diag)));
137:     } else {
138:       PetscCall(PetscViewerASCIIPrintf(viewer, "Diagonal value: %g + i %g\n", (double)PetscRealPart(ctx->diag), (double)PetscImaginaryPart(ctx->diag)));
139:     }
140:   }
141:   PetscFunctionReturn(PETSC_SUCCESS);
142: }

144: static PetscErrorCode MatMult_ConstantDiagonal(Mat J, Vec x, Vec y)
145: {
146:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)J->data;

148:   PetscFunctionBegin;
149:   PetscCall(VecAXPBY(y, ctx->diag, 0.0, x));
150:   PetscFunctionReturn(PETSC_SUCCESS);
151: }

153: static PetscErrorCode MatMultHermitianTranspose_ConstantDiagonal(Mat J, Vec x, Vec y)
154: {
155:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)J->data;

157:   PetscFunctionBegin;
158:   PetscCall(VecAXPBY(y, PetscConj(ctx->diag), 0.0, x));
159:   PetscFunctionReturn(PETSC_SUCCESS);
160: }

162: static PetscErrorCode MatGetDiagonal_ConstantDiagonal(Mat J, Vec x)
163: {
164:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)J->data;

166:   PetscFunctionBegin;
167:   PetscCall(VecSet(x, ctx->diag));
168:   PetscFunctionReturn(PETSC_SUCCESS);
169: }

171: static PetscErrorCode MatShift_ConstantDiagonal(Mat Y, PetscScalar a)
172: {
173:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)Y->data;

175:   PetscFunctionBegin;
176:   ctx->diag += a;
177:   PetscFunctionReturn(PETSC_SUCCESS);
178: }

180: static PetscErrorCode MatScale_ConstantDiagonal(Mat Y, PetscScalar a)
181: {
182:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)Y->data;

184:   PetscFunctionBegin;
185:   ctx->diag *= a;
186:   PetscFunctionReturn(PETSC_SUCCESS);
187: }

189: static PetscErrorCode MatZeroEntries_ConstantDiagonal(Mat Y)
190: {
191:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)Y->data;

193:   PetscFunctionBegin;
194:   ctx->diag = 0.0;
195:   PetscFunctionReturn(PETSC_SUCCESS);
196: }

198: static PetscErrorCode MatConjugate_ConstantDiagonal(Mat Y)
199: {
200:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)Y->data;

202:   PetscFunctionBegin;
203:   ctx->diag = PetscConj(ctx->diag);
204:   PetscFunctionReturn(PETSC_SUCCESS);
205: }

207: static PetscErrorCode MatTranspose_ConstantDiagonal(Mat A, MatReuse reuse, Mat *matout)
208: {
209:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)A->data;

211:   PetscFunctionBegin;
212:   if (reuse == MAT_INPLACE_MATRIX) {
213:     PetscLayout tmplayout = A->rmap;

215:     A->rmap = A->cmap;
216:     A->cmap = tmplayout;
217:   } else {
218:     if (reuse == MAT_INITIAL_MATRIX) {
219:       PetscCall(MatCreateConstantDiagonal(PetscObjectComm((PetscObject)A), A->cmap->n, A->rmap->n, A->cmap->N, A->rmap->N, ctx->diag, matout));
220:     } else {
221:       PetscCall(MatZeroEntries(*matout));
222:       PetscCall(MatShift(*matout, ctx->diag));
223:     }
224:   }
225:   PetscFunctionReturn(PETSC_SUCCESS);
226: }

228: static PetscErrorCode MatSetRandom_ConstantDiagonal(Mat A, PetscRandom rand)
229: {
230:   PetscMPIInt           rank;
231:   MPI_Comm              comm;
232:   PetscScalar           v   = 0.0;
233:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)A->data;

235:   PetscFunctionBegin;
236:   PetscCall(PetscObjectGetComm((PetscObject)A, &comm));
237:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
238:   if (!rank) PetscCall(PetscRandomGetValue(rand, &v));
239:   PetscCallMPI(MPI_Bcast(&v, 1, MPIU_SCALAR, 0, comm));
240:   ctx->diag = v;
241:   PetscFunctionReturn(PETSC_SUCCESS);
242: }

244: static PetscErrorCode MatSolve_ConstantDiagonal(Mat matin, Vec b, Vec x)
245: {
246:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)matin->data;

248:   PetscFunctionBegin;
249:   if (ctx->diag == 0.0) matin->factorerrortype = MAT_FACTOR_NUMERIC_ZEROPIVOT;
250:   else matin->factorerrortype = MAT_FACTOR_NOERROR;
251:   PetscCall(VecAXPBY(x, 1.0 / ctx->diag, 0.0, b));
252:   PetscFunctionReturn(PETSC_SUCCESS);
253: }

255: static PetscErrorCode MatSOR_ConstantDiagonal(Mat matin, Vec x, PetscReal omega, MatSORType flag, PetscReal fshift, PetscInt its, PetscInt lits, Vec y)
256: {
257:   PetscFunctionBegin;
258:   PetscCall(MatSolve_ConstantDiagonal(matin, x, y));
259:   PetscFunctionReturn(PETSC_SUCCESS);
260: }

262: static PetscErrorCode MatGetInfo_ConstantDiagonal(Mat A, MatInfoType flag, MatInfo *info)
263: {
264:   PetscFunctionBegin;
265:   info->block_size   = 1.0;
266:   info->nz_allocated = 1.0;
267:   info->nz_used      = 1.0;
268:   info->nz_unneeded  = 0.0;
269:   info->assemblies   = A->num_ass;
270:   info->mallocs      = 0.0;
271:   info->memory       = 0; /* REVIEW ME */
272:   if (A->factortype) {
273:     info->fill_ratio_given  = 1.0;
274:     info->fill_ratio_needed = 1.0;
275:     info->factor_mallocs    = 0.0;
276:   } else {
277:     info->fill_ratio_given  = 0;
278:     info->fill_ratio_needed = 0;
279:     info->factor_mallocs    = 0;
280:   }
281:   PetscFunctionReturn(PETSC_SUCCESS);
282: }

284: /*@
285:   MatCreateConstantDiagonal - Creates a matrix with a uniform value along the diagonal

287:   Collective

289:   Input Parameters:
290: + comm - MPI communicator
291: . m    - number of local rows (or `PETSC_DECIDE` to have calculated if `M` is given)
292:            This value should be the same as the local size used in creating the
293:            y vector for the matrix-vector product y = Ax.
294: . n    - This value should be the same as the local size used in creating the
295:        x vector for the matrix-vector product y = Ax. (or `PETSC_DECIDE` to have
296:        calculated if `N` is given) For square matrices n is almost always `m`.
297: . M    - number of global rows (or `PETSC_DETERMINE` to have calculated if m is given)
298: . N    - number of global columns (or `PETSC_DETERMINE` to have calculated if n is given)
299: - diag - the diagonal value

301:   Output Parameter:
302: . J - the diagonal matrix

304:   Level: advanced

306:   Notes:
307:   Only supports square matrices with the same number of local rows and columns

309: .seealso: [](ch_matrices), `Mat`, `MatDestroy()`, `MATCONSTANTDIAGONAL`, `MatScale()`, `MatShift()`, `MatMult()`, `MatGetDiagonal()`, `MatGetFactor()`, `MatSolve()`
310: @*/
311: PetscErrorCode MatCreateConstantDiagonal(MPI_Comm comm, PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscScalar diag, Mat *J)
312: {
313:   PetscFunctionBegin;
314:   PetscCall(MatCreate(comm, J));
315:   PetscCall(MatSetSizes(*J, m, n, M, N));
316:   PetscCall(MatSetType(*J, MATCONSTANTDIAGONAL));
317:   PetscCall(MatShift(*J, diag));
318:   PetscCall(MatSetUp(*J));
319:   PetscFunctionReturn(PETSC_SUCCESS);
320: }

322: /*@
323:   MatConstantDiagonalGetConstant - Get the scalar constant of a constant diagonal matrix

325:   Not collective

327:   Input Parameter:
328: . mat - a `MATCONSTANTDIAGONAL`

330:   Output Parameter:
331: . value - the scalar value

333:   Level: developer

335: .seealso: [](ch_matrices), `Mat`, `MatDestroy()`, `MATCONSTANTDIAGONAL`
336: @*/
337: PetscErrorCode MatConstantDiagonalGetConstant(Mat mat, PetscScalar *value)
338: {
339:   PetscFunctionBegin;
340:   PetscUseMethod(mat, "MatConstantDiagonalGetConstant_C", (Mat, PetscScalar *), (mat, value));
341:   PetscFunctionReturn(PETSC_SUCCESS);
342: }

344: static PetscErrorCode MatConstantDiagonalGetConstant_ConstantDiagonal(Mat mat, PetscScalar *value)
345: {
346:   Mat_ConstantDiagonal *ctx = (Mat_ConstantDiagonal *)mat->data;

348:   PetscFunctionBegin;
349:   *value = ctx->diag;
350:   PetscFunctionReturn(PETSC_SUCCESS);
351: }

353: /* PtAP for constantdiagonal * constantdiagonal: C = alpha * beta^2 * I */
354: static PetscErrorCode MatProductNumeric_PtAP_ConstDiag_ConstDiag(Mat C)
355: {
356:   Mat                   A = C->product->A, P = C->product->B;
357:   Mat_ConstantDiagonal *a = (Mat_ConstantDiagonal *)A->data, *p = (Mat_ConstantDiagonal *)P->data, *c = (Mat_ConstantDiagonal *)C->data;

359:   PetscFunctionBegin;
360:   MatCheckProduct(C, 1);
361:   c->diag = a->diag * p->diag * p->diag;
362:   PetscFunctionReturn(PETSC_SUCCESS);
363: }

365: static PetscErrorCode MatProductSymbolic_PtAP_ConstDiag_ConstDiag(Mat C)
366: {
367:   Mat P = C->product->B;

369:   PetscFunctionBegin;
370:   MatCheckProduct(C, 1);
371:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
372:   PetscCall(MatSetSizes(C, P->cmap->n, P->cmap->n, P->cmap->N, P->cmap->N));
373:   PetscCall(MatSetType(C, MATCONSTANTDIAGONAL));
374:   C->assembled           = PETSC_TRUE;
375:   C->ops->productnumeric = MatProductNumeric_PtAP_ConstDiag_ConstDiag;
376:   PetscFunctionReturn(PETSC_SUCCESS);
377: }

379: /* PtAP for constantdiagonal A and diagonal P: C_i = alpha * p_i^2 */
380: static PetscErrorCode MatProductNumeric_PtAP_ConstDiag_Diagonal(Mat C)
381: {
382:   Mat                   A = C->product->A, P = C->product->B;
383:   Mat_ConstantDiagonal *a = (Mat_ConstantDiagonal *)A->data;
384:   Vec                   pdiag, cdiag;

386:   PetscFunctionBegin;
387:   MatCheckProduct(C, 1);
388:   PetscCall(MatDiagonalGetDiagonal(P, &pdiag));
389:   PetscCall(MatDiagonalGetDiagonal(C, &cdiag));
390:   PetscCall(VecPointwiseMult(cdiag, pdiag, pdiag));
391:   PetscCall(VecScale(cdiag, a->diag));
392:   PetscCall(MatDiagonalRestoreDiagonal(C, &cdiag));
393:   PetscCall(MatDiagonalRestoreDiagonal(P, &pdiag));
394:   PetscFunctionReturn(PETSC_SUCCESS);
395: }

397: static PetscErrorCode MatProductSymbolic_PtAP_ConstDiag_Diagonal(Mat C)
398: {
399:   Mat P = C->product->B;
400:   Vec pdiag, cdiag;

402:   PetscFunctionBegin;
403:   MatCheckProduct(C, 1);
404:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
405:   PetscCall(MatSetSizes(C, P->cmap->n, P->cmap->n, P->cmap->N, P->cmap->N));
406:   PetscCall(MatSetType(C, MATDIAGONAL));
407:   PetscCall(MatDiagonalGetDiagonal(P, &pdiag));
408:   PetscCall(VecDuplicate(pdiag, &cdiag));
409:   PetscCall(MatDiagonalSetDiagonal(C, cdiag));
410:   PetscCall(VecDestroy(&cdiag));
411:   PetscCall(MatDiagonalRestoreDiagonal(P, &pdiag));
412:   C->assembled           = PETSC_TRUE;
413:   C->ops->productnumeric = MatProductNumeric_PtAP_ConstDiag_Diagonal;
414:   PetscFunctionReturn(PETSC_SUCCESS);
415: }

417: /* PtAP for diagonal A and constantdiagonal P: C_i = beta^2 * a_i */
418: static PetscErrorCode MatProductNumeric_PtAP_Diagonal_ConstDiag(Mat C)
419: {
420:   Mat                   A = C->product->A, P = C->product->B;
421:   Mat_ConstantDiagonal *p = (Mat_ConstantDiagonal *)P->data;
422:   Vec                   adiag, cdiag;

424:   PetscFunctionBegin;
425:   MatCheckProduct(C, 1);
426:   PetscCall(MatDiagonalGetDiagonal(A, &adiag));
427:   PetscCall(MatDiagonalGetDiagonal(C, &cdiag));
428:   PetscCall(VecCopy(adiag, cdiag));
429:   PetscCall(VecScale(cdiag, p->diag * p->diag));
430:   PetscCall(MatDiagonalRestoreDiagonal(C, &cdiag));
431:   PetscCall(MatDiagonalRestoreDiagonal(A, &adiag));
432:   PetscFunctionReturn(PETSC_SUCCESS);
433: }

435: static PetscErrorCode MatProductSymbolic_PtAP_Diagonal_ConstDiag(Mat C)
436: {
437:   Mat A = C->product->A, P = C->product->B;
438:   Vec adiag, cdiag;

440:   PetscFunctionBegin;
441:   MatCheckProduct(C, 1);
442:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
443:   PetscCall(MatSetSizes(C, P->cmap->n, P->cmap->n, P->cmap->N, P->cmap->N));
444:   PetscCall(MatSetType(C, MATDIAGONAL));
445:   /* Duplicate A's diagonal Vec so C inherits the correct VecType (e.g., Kokkos, CUDA, HIP) */
446:   PetscCall(MatDiagonalGetDiagonal(A, &adiag));
447:   PetscCall(VecDuplicate(adiag, &cdiag));
448:   PetscCall(MatDiagonalSetDiagonal(C, cdiag));
449:   PetscCall(VecDestroy(&cdiag));
450:   PetscCall(MatDiagonalRestoreDiagonal(A, &adiag));
451:   C->assembled           = PETSC_TRUE;
452:   C->ops->productnumeric = MatProductNumeric_PtAP_Diagonal_ConstDiag;
453:   PetscFunctionReturn(PETSC_SUCCESS);
454: }

456: /* PtAP for any (non-diagonal) A and constantdiagonal P: C = beta^2 * A */
457: static PetscErrorCode MatProductNumeric_PtAP_Anytype_ConstDiag(Mat C)
458: {
459:   Mat                   A = C->product->A, P = C->product->B;
460:   Mat_ConstantDiagonal *p = (Mat_ConstantDiagonal *)P->data;

462:   PetscFunctionBegin;
463:   MatCheckProduct(C, 1);
464:   PetscCall(MatCopy(A, C, SAME_NONZERO_PATTERN));
465:   PetscCall(MatScale(C, p->diag * p->diag));
466:   PetscFunctionReturn(PETSC_SUCCESS);
467: }

469: static PetscErrorCode MatProductSymbolic_PtAP_Anytype_ConstDiag(Mat C)
470: {
471:   Mat          A       = C->product->A;
472:   Mat_Product *product = C->product;
473:   Mat          Cwork;

475:   PetscFunctionBegin;
476:   MatCheckProduct(C, 1);
477:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
478:   PetscCall(MatDuplicate(A, MAT_DO_NOT_COPY_VALUES, &Cwork));
479:   C->product = NULL;
480:   PetscCall(MatHeaderReplace(C, &Cwork));
481:   C->product             = product;
482:   C->ops->productnumeric = MatProductNumeric_PtAP_Anytype_ConstDiag;
483:   PetscFunctionReturn(PETSC_SUCCESS);
484: }

486: /* PtAP for constantdiagonal A and any non-diagonal P: C = alpha * P^T * P */
487: typedef struct {
488:   Mat              PtP;       /* P^T * P result via MatProduct AtB */
489:   PetscObjectState pnnzstate; /* P's nonzero state when inner symbolic was last built */
490: } MatProductCtx_PtAP_ConstDiag_Anytype;

492: static PetscErrorCode MatProductCtxDestroy_PtAP_ConstDiag_Anytype(PetscCtxRt data)
493: {
494:   MatProductCtx_PtAP_ConstDiag_Anytype *ctx = *(MatProductCtx_PtAP_ConstDiag_Anytype **)data;

496:   PetscFunctionBegin;
497:   PetscCall(MatDestroy(&ctx->PtP));
498:   PetscCall(PetscFree(ctx));
499:   PetscFunctionReturn(PETSC_SUCCESS);
500: }

502: static PetscErrorCode MatProductNumeric_PtAP_ConstDiag_Anytype(Mat C)
503: {
504:   Mat_Product                          *product = C->product;
505:   Mat                                   A = product->A, P = product->B;
506:   MatProductCtx_PtAP_ConstDiag_Anytype *ctx = (MatProductCtx_PtAP_ConstDiag_Anytype *)product->data;
507:   Mat_ConstantDiagonal                 *a   = (Mat_ConstantDiagonal *)A->data;
508:   PetscObjectState                      pnnzstate;

510:   PetscFunctionBegin;
511:   MatCheckProduct(C, 1);
512:   /* Rebuild inner symbolic if P's nonzero structure has changed */
513:   PetscCall(MatGetNonzeroState(P, &pnnzstate));
514:   if (pnnzstate != ctx->pnnzstate) {
515:     PetscCall(MatDestroy(&ctx->PtP));
516:     PetscCall(MatProductCreate(P, P, NULL, &ctx->PtP));
517:     PetscCall(MatProductSetType(ctx->PtP, MATPRODUCT_AtB));
518:     PetscCall(MatProductSetFill(ctx->PtP, product->fill));
519:     PetscCall(MatProductSetFromOptions(ctx->PtP));
520:     PetscCall(MatProductSymbolic(ctx->PtP));
521:     ctx->pnnzstate = pnnzstate;
522:   }
523:   /* Compute P^T * P */
524:   PetscCall(MatProductNumeric(ctx->PtP));
525:   PetscCall(MatCopy(ctx->PtP, C, SAME_NONZERO_PATTERN));
526:   PetscCall(MatScale(C, a->diag));
527:   PetscFunctionReturn(PETSC_SUCCESS);
528: }

530: static PetscErrorCode MatProductSymbolic_PtAP_ConstDiag_Anytype(Mat C)
531: {
532:   Mat_Product                          *product = C->product;
533:   Mat                                   P       = product->B;
534:   MatProductCtx_PtAP_ConstDiag_Anytype *ctx;
535:   Mat                                   Cwork;

537:   PetscFunctionBegin;
538:   MatCheckProduct(C, 1);
539:   PetscCheck(!C->product->data, PetscObjectComm((PetscObject)C), PETSC_ERR_PLIB, "Product data not empty");
540:   PetscCall(PetscNew(&ctx));

542:   /* PtP = P^T * P (symbolic) */
543:   PetscCall(MatProductCreate(P, P, NULL, &ctx->PtP));
544:   PetscCall(MatProductSetType(ctx->PtP, MATPRODUCT_AtB));
545:   PetscCall(MatProductSetFill(ctx->PtP, product->fill));
546:   PetscCall(MatProductSetFromOptions(ctx->PtP));
547:   PetscCall(MatProductSymbolic(ctx->PtP));

549:   /* Record P's nonzero state so numeric phase can detect structural changes */
550:   PetscCall(MatGetNonzeroState(P, &ctx->pnnzstate));

552:   /* Set up C with the same structure as PtP */
553:   PetscCall(MatDuplicate(ctx->PtP, MAT_DO_NOT_COPY_VALUES, &Cwork));
554:   C->product = NULL;
555:   PetscCall(MatHeaderReplace(C, &Cwork));
556:   C->product             = product;
557:   C->assembled           = PETSC_TRUE;
558:   product->data          = ctx;
559:   product->destroy       = MatProductCtxDestroy_PtAP_ConstDiag_Anytype;
560:   C->ops->productnumeric = MatProductNumeric_PtAP_ConstDiag_Anytype;
561:   PetscFunctionReturn(PETSC_SUCCESS);
562: }

564: static PetscErrorCode MatProductSetFromOptions_ConstDiag_ConstDiag(Mat C)
565: {
566:   Mat_Product *product = C->product;

568:   PetscFunctionBegin;
569:   if (product->type == MATPRODUCT_PtAP) C->ops->productsymbolic = MatProductSymbolic_PtAP_ConstDiag_ConstDiag;
570:   PetscFunctionReturn(PETSC_SUCCESS);
571: }

573: static PetscErrorCode MatProductSetFromOptions_ConstDiag_Diagonal(Mat C)
574: {
575:   Mat_Product *product = C->product;

577:   PetscFunctionBegin;
578:   if (product->type == MATPRODUCT_PtAP) C->ops->productsymbolic = MatProductSymbolic_PtAP_ConstDiag_Diagonal;
579:   PetscFunctionReturn(PETSC_SUCCESS);
580: }

582: static PetscErrorCode MatProductSetFromOptions_Diagonal_ConstDiag(Mat C)
583: {
584:   Mat_Product *product = C->product;

586:   PetscFunctionBegin;
587:   if (product->type == MATPRODUCT_PtAP) C->ops->productsymbolic = MatProductSymbolic_PtAP_Diagonal_ConstDiag;
588:   PetscFunctionReturn(PETSC_SUCCESS);
589: }

591: static PetscErrorCode MatProductSetFromOptions_ConstDiag_Anytype(Mat C)
592: {
593:   Mat_Product *product = C->product;
594:   PetscBool    Acdiag, Bcdiag;

596:   PetscFunctionBegin;
597:   PetscCall(PetscObjectTypeCompare((PetscObject)product->A, MATCONSTANTDIAGONAL, &Acdiag));
598:   PetscCall(PetscObjectTypeCompare((PetscObject)product->B, MATCONSTANTDIAGONAL, &Bcdiag));
599:   if (Acdiag && !Bcdiag && (product->type == MATPRODUCT_PtAP)) C->ops->productsymbolic = MatProductSymbolic_PtAP_ConstDiag_Anytype;
600:   else if (Bcdiag && !Acdiag && (product->type == MATPRODUCT_PtAP)) C->ops->productsymbolic = MatProductSymbolic_PtAP_Anytype_ConstDiag;
601:   PetscFunctionReturn(PETSC_SUCCESS);
602: }

604: /*MC
605:    MATCONSTANTDIAGONAL - "constant-diagonal" - A diagonal matrix type with a uniform value
606:    along the diagonal.

608:   Level: advanced

610: .seealso: [](ch_matrices), `Mat`, `MatCreateConstantDiagonal()`
611: M*/
612: PETSC_EXTERN PetscErrorCode MatCreate_ConstantDiagonal(Mat A)
613: {
614:   Mat_ConstantDiagonal *ctx;

616:   PetscFunctionBegin;
617:   PetscCall(PetscNew(&ctx));
618:   ctx->diag = 0.0;
619:   A->data   = (void *)ctx;

621:   A->assembled                   = PETSC_TRUE;
622:   A->preallocated                = PETSC_TRUE;
623:   A->structurally_symmetric      = PETSC_BOOL3_TRUE;
624:   A->structural_symmetry_eternal = PETSC_TRUE;
625:   A->symmetric                   = PETSC_BOOL3_TRUE;
626:   if (!PetscDefined(USE_COMPLEX)) A->hermitian = PETSC_BOOL3_TRUE;
627:   A->symmetry_eternal = PETSC_TRUE;

629:   A->ops->mult                      = MatMult_ConstantDiagonal;
630:   A->ops->multadd                   = MatMultAdd_ConstantDiagonal;
631:   A->ops->multtranspose             = MatMult_ConstantDiagonal;
632:   A->ops->multtransposeadd          = MatMultAdd_ConstantDiagonal;
633:   A->ops->multhermitiantranspose    = MatMultHermitianTranspose_ConstantDiagonal;
634:   A->ops->multhermitiantransposeadd = MatMultHermitianTransposeAdd_ConstantDiagonal;
635:   A->ops->solve                     = MatSolve_ConstantDiagonal;
636:   A->ops->solvetranspose            = MatSolve_ConstantDiagonal;
637:   A->ops->norm                      = MatNorm_ConstantDiagonal;
638:   A->ops->createsubmatrices         = MatCreateSubMatrices_ConstantDiagonal;
639:   A->ops->duplicate                 = MatDuplicate_ConstantDiagonal;
640:   A->ops->getrow                    = MatGetRow_ConstantDiagonal;
641:   A->ops->restorerow                = MatRestoreRow_ConstantDiagonal;
642:   A->ops->sor                       = MatSOR_ConstantDiagonal;
643:   A->ops->shift                     = MatShift_ConstantDiagonal;
644:   A->ops->scale                     = MatScale_ConstantDiagonal;
645:   A->ops->getdiagonal               = MatGetDiagonal_ConstantDiagonal;
646:   A->ops->view                      = MatView_ConstantDiagonal;
647:   A->ops->zeroentries               = MatZeroEntries_ConstantDiagonal;
648:   A->ops->destroy                   = MatDestroy_ConstantDiagonal;
649:   A->ops->getinfo                   = MatGetInfo_ConstantDiagonal;
650:   A->ops->equal                     = MatEqual_ConstantDiagonal;
651:   A->ops->axpy                      = MatAXPY_ConstantDiagonal;
652:   A->ops->setrandom                 = MatSetRandom_ConstantDiagonal;
653:   A->ops->conjugate                 = MatConjugate_ConstantDiagonal;
654:   A->ops->transpose                 = MatTranspose_ConstantDiagonal;

656:   PetscCall(PetscObjectChangeTypeName((PetscObject)A, MATCONSTANTDIAGONAL));
657:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatConstantDiagonalGetConstant_C", MatConstantDiagonalGetConstant_ConstantDiagonal));
658:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_constantdiagonal_constantdiagonal_C", MatProductSetFromOptions_ConstDiag_ConstDiag));
659:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_constantdiagonal_diagonal_C", MatProductSetFromOptions_ConstDiag_Diagonal));
660:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_diagonal_constantdiagonal_C", MatProductSetFromOptions_Diagonal_ConstDiag));
661:   PetscCall(PetscObjectComposeFunction((PetscObject)A, "MatProductSetFromOptions_anytype_C", MatProductSetFromOptions_ConstDiag_Anytype));
662:   PetscFunctionReturn(PETSC_SUCCESS);
663: }

665: static PetscErrorCode MatFactorNumeric_ConstantDiagonal(Mat fact, Mat A, const MatFactorInfo *info)
666: {
667:   Mat_ConstantDiagonal *actx = (Mat_ConstantDiagonal *)A->data, *fctx = (Mat_ConstantDiagonal *)fact->data;

669:   PetscFunctionBegin;
670:   if (actx->diag == 0.0) fact->factorerrortype = MAT_FACTOR_NUMERIC_ZEROPIVOT;
671:   else fact->factorerrortype = MAT_FACTOR_NOERROR;
672:   fctx->diag       = 1.0 / actx->diag;
673:   fact->ops->solve = MatMult_ConstantDiagonal;
674:   PetscFunctionReturn(PETSC_SUCCESS);
675: }

677: static PetscErrorCode MatFactorSymbolic_LU_ConstantDiagonal(Mat fact, Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
678: {
679:   PetscFunctionBegin;
680:   fact->ops->lufactornumeric = MatFactorNumeric_ConstantDiagonal;
681:   PetscFunctionReturn(PETSC_SUCCESS);
682: }

684: static PetscErrorCode MatFactorSymbolic_Cholesky_ConstantDiagonal(Mat fact, Mat A, IS isrow, const MatFactorInfo *info)
685: {
686:   PetscFunctionBegin;
687:   fact->ops->choleskyfactornumeric = MatFactorNumeric_ConstantDiagonal;
688:   PetscFunctionReturn(PETSC_SUCCESS);
689: }

691: PETSC_INTERN PetscErrorCode MatGetFactor_constantdiagonal_petsc(Mat A, MatFactorType ftype, Mat *B)
692: {
693:   PetscInt n = A->rmap->n, N = A->rmap->N;

695:   PetscFunctionBegin;
696:   PetscCall(MatCreateConstantDiagonal(PetscObjectComm((PetscObject)A), n, n, N, N, 0, B));

698:   (*B)->factortype                  = ftype;
699:   (*B)->ops->ilufactorsymbolic      = MatFactorSymbolic_LU_ConstantDiagonal;
700:   (*B)->ops->lufactorsymbolic       = MatFactorSymbolic_LU_ConstantDiagonal;
701:   (*B)->ops->iccfactorsymbolic      = MatFactorSymbolic_Cholesky_ConstantDiagonal;
702:   (*B)->ops->choleskyfactorsymbolic = MatFactorSymbolic_Cholesky_ConstantDiagonal;

704:   (*B)->ops->shift       = NULL;
705:   (*B)->ops->scale       = NULL;
706:   (*B)->ops->mult        = NULL;
707:   (*B)->ops->sor         = NULL;
708:   (*B)->ops->zeroentries = NULL;

710:   PetscCall(PetscFree((*B)->solvertype));
711:   PetscCall(PetscStrallocpy(MATSOLVERPETSC, &(*B)->solvertype));
712:   PetscFunctionReturn(PETSC_SUCCESS);
713: }