Actual source code: rvector.c

  1: /*
  2:      Provides the interface functions for vector operations that have PetscScalar/PetscReal in the signature
  3:    These are the vector functions the user calls.
  4: */
  5: #include <petsc/private/vecimpl.h>

  7: PetscInt VecGetSubVectorSavedStateId = -1;

  9: #if PetscDefined(USE_DEBUG)
 10: // this is a no-op '0' macro in optimized builds
 11: PetscErrorCode VecValidValues_Internal(Vec vec, PetscInt argnum, PetscBool begin)
 12: {
 13:   PetscFunctionBegin;
 14:   if (vec->petscnative || vec->ops->getarray) {
 15:     PetscInt           n;
 16:     const PetscScalar *x;
 17:     PetscOffloadMask   mask;

 19:     PetscCall(VecGetOffloadMask(vec, &mask));
 20:     if (!PetscOffloadHost(mask)) PetscFunctionReturn(PETSC_SUCCESS);
 21:     PetscCall(VecGetLocalSize(vec, &n));
 22:     PetscCall(VecGetArrayRead(vec, &x));
 23:     for (PetscInt i = 0; i < n; i++) {
 24:       if (begin) {
 25:         PetscCheck(!PetscIsInfOrNanScalar(x[i]), PETSC_COMM_SELF, PETSC_ERR_FP, "Vec entry at local location %" PetscInt_FMT " is not-a-number or infinite at beginning of function: Parameter number %" PetscInt_FMT, i, argnum);
 26:       } else {
 27:         PetscCheck(!PetscIsInfOrNanScalar(x[i]), PETSC_COMM_SELF, PETSC_ERR_FP, "Vec entry at local location %" PetscInt_FMT " is not-a-number or infinite at end of function: Parameter number %" PetscInt_FMT, i, argnum);
 28:       }
 29:     }
 30:     PetscCall(VecRestoreArrayRead(vec, &x));
 31:   }
 32:   PetscFunctionReturn(PETSC_SUCCESS);
 33: }
 34: #endif

 36: /*@
 37:   VecMaxPointwiseDivide - Computes the maximum of the componentwise division `max = max_i abs(x[i]/y[i])`.

 39:   Logically Collective

 41:   Input Parameters:
 42: + x - the numerators
 43: - y - the denominators

 45:   Output Parameter:
 46: . max - the result

 48:   Level: advanced

 50:   Notes:
 51:   `x` and `y` may be the same vector

 53:   if a particular `y[i]` is zero, it is treated as 1 in the above formula

 55: .seealso: [](ch_vectors), `Vec`, `VecPointwiseDivide()`, `VecPointwiseMult()`, `VecPointwiseMax()`, `VecPointwiseMin()`, `VecPointwiseMaxAbs()`
 56: @*/
 57: PetscErrorCode VecMaxPointwiseDivide(Vec x, Vec y, PetscReal *max)
 58: {
 59:   PetscFunctionBegin;
 62:   PetscAssertPointer(max, 3);
 65:   PetscCheckSameTypeAndComm(x, 1, y, 2);
 66:   VecCheckSameSize(x, 1, y, 2);
 67:   VecCheckAssembled(x);
 68:   VecCheckAssembled(y);
 69:   PetscCall(VecLockReadPush(x));
 70:   PetscCall(VecLockReadPush(y));
 71:   PetscUseTypeMethod(x, maxpointwisedivide, y, max);
 72:   PetscCall(VecLockReadPop(x));
 73:   PetscCall(VecLockReadPop(y));
 74:   PetscFunctionReturn(PETSC_SUCCESS);
 75: }

 77: /*@
 78:   VecDot - Computes the vector dot product.

 80:   Collective

 82:   Input Parameters:
 83: + x - first vector
 84: - y - second vector

 86:   Output Parameter:
 87: . val - the dot product

 89:   Level: intermediate

 91:   Notes for Users of Complex Numbers:
 92:   For complex vectors, `VecDot()` computes
 93: .vb
 94:   val = (x,y) = y^H x,
 95: .ve
 96:   where y^H denotes the conjugate transpose of y. Note that this corresponds to the usual "mathematicians" complex
 97:   inner product where the SECOND argument gets the complex conjugate. Since the `BLASdot()` complex conjugates the first
 98:   first argument we call the `BLASdot()` with the arguments reversed.

100:   Use `VecTDot()` for the indefinite form
101: .vb
102:   val = (x,y) = y^T x,
103: .ve
104:   where y^T denotes the transpose of y.

106: .seealso: [](ch_vectors), `Vec`, `VecMDot()`, `VecTDot()`, `VecNorm()`, `VecDotBegin()`, `VecDotEnd()`, `VecDotRealPart()`
107: @*/
108: PetscErrorCode VecDot(Vec x, Vec y, PetscScalar *val)
109: {
110:   PetscFunctionBegin;
113:   PetscAssertPointer(val, 3);
116:   PetscCheckSameTypeAndComm(x, 1, y, 2);
117:   VecCheckSameSize(x, 1, y, 2);
118:   VecCheckAssembled(x);
119:   VecCheckAssembled(y);

121:   PetscCall(VecLockReadPush(x));
122:   PetscCall(VecLockReadPush(y));
123:   PetscCall(PetscLogEventBegin(VEC_Dot, x, y, 0, 0));
124:   PetscUseTypeMethod(x, dot, y, val);
125:   PetscCall(PetscLogEventEnd(VEC_Dot, x, y, 0, 0));
126:   PetscCall(VecLockReadPop(x));
127:   PetscCall(VecLockReadPop(y));
128:   PetscFunctionReturn(PETSC_SUCCESS);
129: }

131: /*@
132:   VecDotRealPart - Computes the real part of the vector dot product.

134:   Collective

136:   Input Parameters:
137: + x - first vector
138: - y - second vector

140:   Output Parameter:
141: . val - the real part of the dot product;

143:   Level: intermediate

145:   Notes for Users of Complex Numbers:
146:   See `VecDot()` for more details on the definition of the dot product for complex numbers

148:   For real numbers this returns the same value as `VecDot()`

150:   For complex numbers in C^n (that is a vector of n components with a complex number for each component) this is equal to the usual real dot product on the
151:   the space R^{2n} (that is a vector of 2n components with the real or imaginary part of the complex numbers for components)

153:   Developer Notes:
154:   This is not currently optimized to compute only the real part of the dot product.

156: .seealso: [](ch_vectors), `Vec`, `VecMDot()`, `VecTDot()`, `VecNorm()`, `VecDotBegin()`, `VecDotEnd()`, `VecDot()`, `VecDotNorm2()`
157: @*/
158: PetscErrorCode VecDotRealPart(Vec x, Vec y, PetscReal *val)
159: {
160:   PetscScalar fdot;

162:   PetscFunctionBegin;
163:   PetscCall(VecDot(x, y, &fdot));
164:   *val = PetscRealPart(fdot);
165:   PetscFunctionReturn(PETSC_SUCCESS);
166: }

168: /*@
169:   VecNorm  - Computes the vector norm.

171:   Collective

173:   Input Parameters:
174: + x    - the vector
175: - type - the type of the norm requested

177:   Output Parameter:
178: . val - the norm

180:   Level: intermediate

182:   Notes:
183:   See `NormType` for descriptions of each norm.

185:   For complex numbers `NORM_1` will return the traditional 1 norm of the 2 norm of the complex
186:   numbers; that is the 1 norm of the absolute values of the complex entries. In PETSc 3.6 and
187:   earlier releases it returned the 1 norm of the 1 norm of the complex entries (what is
188:   returned by the BLAS routine `asum()`). Both are valid norms but most people expect the former.

190:   This routine stashes the computed norm value, repeated calls before the vector entries are
191:   changed are then rapid since the precomputed value is immediately available. Certain vector
192:   operations such as `VecSet()` store the norms so the value is immediately available and does
193:   not need to be explicitly computed. `VecScale()` updates any stashed norm values, thus calls
194:   after `VecScale()` do not need to explicitly recompute the norm.

196: .seealso: [](ch_vectors), `Vec`, `NormType`, `VecDot()`, `VecTDot()`, `VecDotBegin()`, `VecDotEnd()`, `VecNormAvailable()`,
197:           `VecNormBegin()`, `VecNormEnd()`, `NormType()`
198: @*/
199: PetscErrorCode VecNorm(Vec x, NormType type, PetscReal *val)
200: {
201:   PetscBool flg = PETSC_TRUE;

203:   PetscFunctionBegin;
206:   VecCheckAssembled(x);
208:   PetscAssertPointer(val, 3);

210:   PetscCall(VecNormAvailable(x, type, &flg, val));
211:   // check that all MPI processes call this routine together and have same availability
212:   if (PetscDefined(USE_DEBUG)) {
213:     PetscMPIInt b0 = (PetscMPIInt)flg, b1[2], b2[2];
214:     b1[0]          = -b0;
215:     b1[1]          = b0;
216:     PetscCallMPI(MPIU_Allreduce(b1, b2, 2, MPI_INT, MPI_MAX, PetscObjectComm((PetscObject)x)));
217:     PetscCheck(-b2[0] == b2[1], PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONGSTATE, "Some MPI processes have cached %s norm, others do not. This may happen when some MPI processes call VecGetArray() and some others do not.", NormTypes[type]);
218:     if (flg) {
219:       PetscReal b1[2], b2[2];
220:       b1[0] = -(*val);
221:       b1[1] = *val;
222:       PetscCallMPI(MPIU_Allreduce(b1, b2, 2, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)x)));
223:       PetscCheck((PetscIsNanReal(b2[0]) && PetscIsNanReal(b2[1])) || (-b2[0] == b2[1]), PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Difference in cached %s norms: local %g", NormTypes[type], (double)*val);
224:     }
225:   }
226:   if (flg) PetscFunctionReturn(PETSC_SUCCESS);

228:   PetscCall(VecLockReadPush(x));
229:   PetscCall(PetscLogEventBegin(VEC_Norm, x, 0, 0, 0));
230:   PetscUseTypeMethod(x, norm, type, val);
231:   PetscCall(PetscLogEventEnd(VEC_Norm, x, 0, 0, 0));
232:   PetscCall(VecLockReadPop(x));

234:   if (type != NORM_1_AND_2) PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[type], *val));
235:   PetscFunctionReturn(PETSC_SUCCESS);
236: }

238: /*@
239:   VecNormAvailable  - Returns the vector norm if it is already known. That is, it has been previously computed and cached in the vector

241:   Not Collective

243:   Input Parameters:
244: + x    - the vector
245: - type - one of `NORM_1` (sum_i |x[i]|), `NORM_2` sqrt(sum_i (x[i])^2), `NORM_INFINITY` max_i |x[i]|.  Also available
246:           `NORM_1_AND_2`, which computes both norms and stores them
247:           in a two element array.

249:   Output Parameters:
250: + available - `PETSC_TRUE` if the val returned is valid
251: - val       - the norm

253:   Level: intermediate

255:   Developer Notes:
256:   `PETSC_HAVE_SLOW_BLAS_NORM2` will cause a C (loop unrolled) version of the norm to be used, rather
257:   than the BLAS. This should probably only be used when one is using the FORTRAN BLAS routines
258:   (as opposed to vendor provided) because the FORTRAN BLAS `NRM2()` routine is very slow.

260: .seealso: [](ch_vectors), `Vec`, `VecDot()`, `VecTDot()`, `VecNorm()`, `VecDotBegin()`, `VecDotEnd()`,
261:           `VecNormBegin()`, `VecNormEnd()`
262: @*/
263: PetscErrorCode VecNormAvailable(Vec x, NormType type, PetscBool *available, PetscReal *val)
264: {
265:   PetscFunctionBegin;
268:   PetscAssertPointer(available, 3);
269:   PetscAssertPointer(val, 4);

271:   if (type == NORM_1_AND_2) {
272:     *available = PETSC_FALSE;
273:   } else {
274:     PetscCall(PetscObjectComposedDataGetReal((PetscObject)x, NormIds[type], *val, *available));
275:   }
276:   PetscFunctionReturn(PETSC_SUCCESS);
277: }

279: /*@
280:   VecNormalize - Normalizes a vector by its 2-norm.

282:   Collective

284:   Input Parameter:
285: . x - the vector

287:   Output Parameter:
288: . val - the vector norm before normalization. May be `NULL` if the value is not needed.

290:   Level: intermediate

292: .seealso: [](ch_vectors), `Vec`, `VecNorm()`, `NORM_2`, `NormType`
293: @*/
294: PetscErrorCode VecNormalize(Vec x, PetscReal *val)
295: {
296:   PetscReal norm;

298:   PetscFunctionBegin;
301:   PetscCall(VecSetErrorIfLocked(x, 1));
302:   if (val) PetscAssertPointer(val, 2);
303:   PetscCall(PetscLogEventBegin(VEC_Normalize, x, 0, 0, 0));
304:   PetscCall(VecNorm(x, NORM_2, &norm));
305:   if (norm == 0.0) PetscCall(PetscInfo(x, "Vector of zero norm can not be normalized; Returning only the zero norm\n"));
306:   else if (PetscIsInfOrNanReal(norm)) PetscCall(PetscInfo(x, "Vector with Inf or Nan norm can not be normalized; Returning only the norm\n"));
307:   else {
308:     PetscScalar s = 1.0 / norm;
309:     PetscCall(VecScale(x, s));
310:   }
311:   PetscCall(PetscLogEventEnd(VEC_Normalize, x, 0, 0, 0));
312:   if (val) *val = norm;
313:   PetscFunctionReturn(PETSC_SUCCESS);
314: }

316: /*@
317:   VecMax - Determines the vector component with maximum real part and its location.

319:   Collective

321:   Input Parameter:
322: . x - the vector

324:   Output Parameters:
325: + p   - the index of `val` (pass `NULL` if you don't want this) in the vector
326: - val - the maximum component

328:   Level: intermediate

330:   Notes:
331:   Returns the value `PETSC_MIN_REAL` and negative `p` if the vector is of length 0.

333:   Returns the smallest index with the maximum value

335:   Developer Note:
336:   The Nag Fortran compiler does not like the symbol name VecMax

338: .seealso: [](ch_vectors), `Vec`, `VecNorm()`, `VecMin()`
339: @*/
340: PetscErrorCode VecMax(Vec x, PetscInt *p, PetscReal *val)
341: {
342:   PetscFunctionBegin;
345:   VecCheckAssembled(x);
346:   if (p) PetscAssertPointer(p, 2);
347:   PetscAssertPointer(val, 3);
348:   PetscCall(VecLockReadPush(x));
349:   PetscCall(PetscLogEventBegin(VEC_Max, x, 0, 0, 0));
350:   PetscUseTypeMethod(x, max, p, val);
351:   PetscCall(PetscLogEventEnd(VEC_Max, x, 0, 0, 0));
352:   PetscCall(VecLockReadPop(x));
353:   PetscFunctionReturn(PETSC_SUCCESS);
354: }

356: /*@
357:   VecMin - Determines the vector component with minimum real part and its location.

359:   Collective

361:   Input Parameter:
362: . x - the vector

364:   Output Parameters:
365: + p   - the index of `val` (pass `NULL` if you don't want this location) in the vector
366: - val - the minimum component

368:   Level: intermediate

370:   Notes:
371:   Returns the value `PETSC_MAX_REAL` and negative `p` if the vector is of length 0.

373:   This returns the smallest index with the minimum value

375:   Developer Note:
376:   The Nag Fortran compiler does not like the symbol name VecMin

378: .seealso: [](ch_vectors), `Vec`, `VecMax()`
379: @*/
380: PetscErrorCode VecMin(Vec x, PetscInt *p, PetscReal *val)
381: {
382:   PetscFunctionBegin;
385:   VecCheckAssembled(x);
386:   if (p) PetscAssertPointer(p, 2);
387:   PetscAssertPointer(val, 3);
388:   PetscCall(VecLockReadPush(x));
389:   PetscCall(PetscLogEventBegin(VEC_Min, x, 0, 0, 0));
390:   PetscUseTypeMethod(x, min, p, val);
391:   PetscCall(PetscLogEventEnd(VEC_Min, x, 0, 0, 0));
392:   PetscCall(VecLockReadPop(x));
393:   PetscFunctionReturn(PETSC_SUCCESS);
394: }

396: /*@
397:   VecTDot - Computes an indefinite vector dot product. That is, this
398:   routine does NOT use the complex conjugate.

400:   Collective

402:   Input Parameters:
403: + x - first vector
404: - y - second vector

406:   Output Parameter:
407: . val - the dot product

409:   Level: intermediate

411:   Notes for Users of Complex Numbers:
412:   For complex vectors, `VecTDot()` computes the indefinite form
413: .vb
414:   val = (x,y) = y^T x,
415: .ve
416:   where y^T denotes the transpose of y.

418:   Use `VecDot()` for the inner product
419: .vb
420:   val = (x,y) = y^H x,
421: .ve
422:   where y^H denotes the conjugate transpose of y.

424: .seealso: [](ch_vectors), `Vec`, `VecDot()`, `VecMTDot()`
425: @*/
426: PetscErrorCode VecTDot(Vec x, Vec y, PetscScalar *val)
427: {
428:   PetscFunctionBegin;
431:   PetscAssertPointer(val, 3);
434:   PetscCheckSameTypeAndComm(x, 1, y, 2);
435:   VecCheckSameSize(x, 1, y, 2);
436:   VecCheckAssembled(x);
437:   VecCheckAssembled(y);

439:   PetscCall(VecLockReadPush(x));
440:   PetscCall(VecLockReadPush(y));
441:   PetscCall(PetscLogEventBegin(VEC_TDot, x, y, 0, 0));
442:   PetscUseTypeMethod(x, tdot, y, val);
443:   PetscCall(PetscLogEventEnd(VEC_TDot, x, y, 0, 0));
444:   PetscCall(VecLockReadPop(x));
445:   PetscCall(VecLockReadPop(y));
446:   PetscFunctionReturn(PETSC_SUCCESS);
447: }

449: PetscErrorCode VecScaleAsync_Private(Vec x, PetscScalar alpha, PetscDeviceContext dctx)
450: {
451:   PetscReal   norms[4];
452:   PetscBool   flgs[4];
453:   PetscScalar one = 1.0;

455:   PetscFunctionBegin;
458:   VecCheckAssembled(x);
459:   PetscCall(VecSetErrorIfLocked(x, 1));
461:   if (alpha == one) PetscFunctionReturn(PETSC_SUCCESS);

463:   /* get current stashed norms */
464:   for (PetscInt i = 0; i < 4; i++) PetscCall(PetscObjectComposedDataGetReal((PetscObject)x, NormIds[i], norms[i], flgs[i]));

466:   PetscCall(PetscLogEventBegin(VEC_Scale, x, 0, 0, 0));
467:   VecMethodDispatch(x, dctx, VecAsyncFnName(Scale), scale, (Vec, PetscScalar, PetscDeviceContext), alpha);
468:   PetscCall(PetscLogEventEnd(VEC_Scale, x, 0, 0, 0));

470:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
471:   /* put the scaled stashed norms back into the Vec */
472:   for (PetscInt i = 0; i < 4; i++) {
473:     PetscReal ar = PetscAbsScalar(alpha);
474:     if (flgs[i]) PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[i], ar * norms[i]));
475:   }
476:   PetscFunctionReturn(PETSC_SUCCESS);
477: }

479: /*@
480:   VecScale - Scales a vector.

482:   Logically Collective

484:   Input Parameters:
485: + x     - the vector
486: - alpha - the scalar

488:   Level: intermediate

490:   Note:
491:   For a vector with n components, `VecScale()` computes  x[i] = alpha * x[i], for i=1,...,n.

493: .seealso: [](ch_vectors), `Vec`, `VecSet()`
494: @*/
495: PetscErrorCode VecScale(Vec x, PetscScalar alpha)
496: {
497:   PetscFunctionBegin;
498:   PetscCall(VecScaleAsync_Private(x, alpha, NULL));
499:   PetscFunctionReturn(PETSC_SUCCESS);
500: }

502: PetscErrorCode VecSetAsync_Private(Vec x, PetscScalar alpha, PetscDeviceContext dctx)
503: {
504:   PetscFunctionBegin;
507:   VecCheckAssembled(x);
509:   PetscCall(VecSetErrorIfLocked(x, 1));

511:   if (alpha == 0) {
512:     PetscReal norm;
513:     PetscBool set;

515:     PetscCall(VecNormAvailable(x, NORM_2, &set, &norm));
516:     if (set == PETSC_TRUE && norm == 0) PetscFunctionReturn(PETSC_SUCCESS);
517:   }
518:   PetscCall(PetscLogEventBegin(VEC_Set, x, 0, 0, 0));
519:   VecMethodDispatch(x, dctx, VecAsyncFnName(Set), set, (Vec, PetscScalar, PetscDeviceContext), alpha);
520:   PetscCall(PetscLogEventEnd(VEC_Set, x, 0, 0, 0));
521:   PetscCall(PetscObjectStateIncrease((PetscObject)x));

523:   /*  norms can be simply set (if |alpha|*N not too large) */
524:   {
525:     PetscReal      val = PetscAbsScalar(alpha);
526:     const PetscInt N   = x->map->N;

528:     if (N == 0) {
529:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_1], 0.0));
530:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_INFINITY], 0.0));
531:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_2], 0.0));
532:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_FROBENIUS], 0.0));
533:     } else if (val > PETSC_MAX_REAL / N) {
534:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_INFINITY], val));
535:     } else {
536:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_1], N * val));
537:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_INFINITY], val));
538:       val *= PetscSqrtReal((PetscReal)N);
539:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_2], val));
540:       PetscCall(PetscObjectComposedDataSetReal((PetscObject)x, NormIds[NORM_FROBENIUS], val));
541:     }
542:   }
543:   PetscFunctionReturn(PETSC_SUCCESS);
544: }

546: /*@
547:   VecSet - Sets all components of a vector to a single scalar value.

549:   Logically Collective

551:   Input Parameters:
552: + x     - the vector
553: - alpha - the scalar

555:   Level: beginner

557:   Notes:
558:   For a vector of dimension n, `VecSet()` sets x[i] = alpha, for i=1,...,n,
559:   so that all vector entries then equal the identical
560:   scalar value, `alpha`.  Use the more general routine
561:   `VecSetValues()` to set different vector entries.

563:   You CANNOT call this after you have called `VecSetValues()` but before you call
564:   `VecAssemblyBegin()`

566:   If `alpha` is zero and the norm of the vector is known to be zero then this skips the unneeded zeroing process

568: .seealso: [](ch_vectors), `Vec`, `VecSetValues()`, `VecSetValuesBlocked()`, `VecSetRandom()`
569: @*/
570: PetscErrorCode VecSet(Vec x, PetscScalar alpha)
571: {
572:   PetscFunctionBegin;
573:   PetscCall(VecSetAsync_Private(x, alpha, NULL));
574:   PetscFunctionReturn(PETSC_SUCCESS);
575: }

577: PetscErrorCode VecAXPYAsync_Private(Vec y, PetscScalar alpha, Vec x, PetscDeviceContext dctx)
578: {
579:   PetscFunctionBegin;
584:   PetscCheckSameTypeAndComm(x, 3, y, 1);
585:   VecCheckSameSize(x, 3, y, 1);
586:   VecCheckAssembled(x);
587:   VecCheckAssembled(y);
589:   if (alpha == (PetscScalar)0.0) PetscFunctionReturn(PETSC_SUCCESS);
590:   PetscCall(VecSetErrorIfLocked(y, 1));
591:   if (x == y) {
592:     PetscCall(VecScale(y, alpha + 1.0));
593:     PetscFunctionReturn(PETSC_SUCCESS);
594:   }
595:   PetscCall(VecLockReadPush(x));
596:   PetscCall(PetscLogEventBegin(VEC_AXPY, x, y, 0, 0));
597:   VecMethodDispatch(y, dctx, VecAsyncFnName(AXPY), axpy, (Vec, PetscScalar, Vec, PetscDeviceContext), alpha, x);
598:   PetscCall(PetscLogEventEnd(VEC_AXPY, x, y, 0, 0));
599:   PetscCall(VecLockReadPop(x));
600:   PetscCall(PetscObjectStateIncrease((PetscObject)y));
601:   PetscFunctionReturn(PETSC_SUCCESS);
602: }
603: /*@
604:   VecAXPY - Computes `y = alpha x + y`.

606:   Logically Collective

608:   Input Parameters:
609: + alpha - the scalar
610: . x     - vector scale by `alpha`
611: - y     - vector accumulated into

613:   Output Parameter:
614: . y - output vector

616:   Level: intermediate

618:   Notes:
619:   This routine is optimized for alpha of 0.0, otherwise it calls the BLAS routine
620: .vb
621:     VecAXPY(y,alpha,x)                   y = alpha x           +      y
622:     VecAYPX(y,beta,x)                    y =       x           + beta y
623:     VecAXPBY(y,alpha,beta,x)             y = alpha x           + beta y
624:     VecWAXPY(w,alpha,x,y)                w = alpha x           +      y
625:     VecAXPBYPCZ(z,alpha,beta,gamma,x,y)  z = alpha x           + beta y + gamma z
626:     VecMAXPY(y,nv,alpha[],x[])           y = sum alpha[i] x[i] +      y
627: .ve

629: .seealso: [](ch_vectors), `Vec`, `VecAYPX()`, `VecMAXPY()`, `VecWAXPY()`, `VecAXPBYPCZ()`, `VecAXPBY()`
630: @*/
631: PetscErrorCode VecAXPY(Vec y, PetscScalar alpha, Vec x)
632: {
633:   PetscFunctionBegin;
634:   PetscCall(VecAXPYAsync_Private(y, alpha, x, NULL));
635:   PetscFunctionReturn(PETSC_SUCCESS);
636: }

638: PetscErrorCode VecAYPXAsync_Private(Vec y, PetscScalar beta, Vec x, PetscDeviceContext dctx)
639: {
640:   PetscFunctionBegin;
645:   PetscCheckSameTypeAndComm(x, 3, y, 1);
646:   VecCheckSameSize(x, 1, y, 3);
647:   VecCheckAssembled(x);
648:   VecCheckAssembled(y);
650:   PetscCall(VecSetErrorIfLocked(y, 1));
651:   if (x == y) {
652:     PetscCall(VecScale(y, beta + 1.0));
653:     PetscFunctionReturn(PETSC_SUCCESS);
654:   }
655:   PetscCall(VecLockReadPush(x));
656:   if (beta == (PetscScalar)0.0) {
657:     PetscCall(VecCopy(x, y));
658:   } else {
659:     PetscCall(PetscLogEventBegin(VEC_AYPX, x, y, 0, 0));
660:     VecMethodDispatch(y, dctx, VecAsyncFnName(AYPX), aypx, (Vec, PetscScalar, Vec, PetscDeviceContext), beta, x);
661:     PetscCall(PetscLogEventEnd(VEC_AYPX, x, y, 0, 0));
662:     PetscCall(PetscObjectStateIncrease((PetscObject)y));
663:   }
664:   PetscCall(VecLockReadPop(x));
665:   PetscFunctionReturn(PETSC_SUCCESS);
666: }

668: /*@
669:   VecAYPX - Computes `y = x + beta y`.

671:   Logically Collective

673:   Input Parameters:
674: + beta - the scalar
675: . x    - the unscaled vector
676: - y    - the vector to be scaled

678:   Output Parameter:
679: . y - output vector

681:   Level: intermediate

683:   Developer Notes:
684:   The implementation is optimized for `beta` of -1.0, 0.0, and 1.0

686: .seealso: [](ch_vectors), `Vec`, `VecMAXPY()`, `VecWAXPY()`, `VecAXPY()`, `VecAXPBYPCZ()`, `VecAXPBY()`
687: @*/
688: PetscErrorCode VecAYPX(Vec y, PetscScalar beta, Vec x)
689: {
690:   PetscFunctionBegin;
691:   PetscCall(VecAYPXAsync_Private(y, beta, x, NULL));
692:   PetscFunctionReturn(PETSC_SUCCESS);
693: }

695: PetscErrorCode VecAXPBYAsync_Private(Vec y, PetscScalar alpha, PetscScalar beta, Vec x, PetscDeviceContext dctx)
696: {
697:   PetscFunctionBegin;
702:   PetscCheckSameTypeAndComm(x, 4, y, 1);
703:   VecCheckSameSize(y, 1, x, 4);
704:   VecCheckAssembled(x);
705:   VecCheckAssembled(y);
708:   if (alpha == (PetscScalar)0.0 && beta == (PetscScalar)1.0) PetscFunctionReturn(PETSC_SUCCESS);
709:   if (x == y) {
710:     PetscCall(VecScale(y, alpha + beta));
711:     PetscFunctionReturn(PETSC_SUCCESS);
712:   }

714:   PetscCall(VecSetErrorIfLocked(y, 1));
715:   PetscCall(VecLockReadPush(x));
716:   PetscCall(PetscLogEventBegin(VEC_AXPY, y, x, 0, 0));
717:   VecMethodDispatch(y, dctx, VecAsyncFnName(AXPBY), axpby, (Vec, PetscScalar, PetscScalar, Vec, PetscDeviceContext), alpha, beta, x);
718:   PetscCall(PetscLogEventEnd(VEC_AXPY, y, x, 0, 0));
719:   PetscCall(PetscObjectStateIncrease((PetscObject)y));
720:   PetscCall(VecLockReadPop(x));
721:   PetscFunctionReturn(PETSC_SUCCESS);
722: }

724: /*@
725:   VecAXPBY - Computes `y = alpha x + beta y`.

727:   Logically Collective

729:   Input Parameters:
730: + alpha - first scalar
731: . beta  - second scalar
732: . x     - the first scaled vector
733: - y     - the second scaled vector

735:   Output Parameter:
736: . y - output vector

738:   Level: intermediate

740:   Developer Notes:
741:   The implementation is optimized for `alpha` and/or `beta` values of 0.0 and 1.0

743: .seealso: [](ch_vectors), `Vec`, `VecAYPX()`, `VecMAXPY()`, `VecWAXPY()`, `VecAXPY()`, `VecAXPBYPCZ()`
744: @*/
745: PetscErrorCode VecAXPBY(Vec y, PetscScalar alpha, PetscScalar beta, Vec x)
746: {
747:   PetscFunctionBegin;
748:   PetscCall(VecAXPBYAsync_Private(y, alpha, beta, x, NULL));
749:   PetscFunctionReturn(PETSC_SUCCESS);
750: }

752: PetscErrorCode VecAXPBYPCZAsync_Private(Vec z, PetscScalar alpha, PetscScalar beta, PetscScalar gamma, Vec x, Vec y, PetscDeviceContext dctx)
753: {
754:   PetscFunctionBegin;
761:   PetscCheckSameTypeAndComm(x, 5, y, 6);
762:   PetscCheckSameTypeAndComm(x, 5, z, 1);
763:   VecCheckSameSize(x, 5, y, 6);
764:   VecCheckSameSize(x, 5, z, 1);
765:   PetscCheck(x != y && x != z, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_IDN, "x, y, and z must be different vectors");
766:   PetscCheck(y != z, PetscObjectComm((PetscObject)y), PETSC_ERR_ARG_IDN, "x, y, and z must be different vectors");
767:   VecCheckAssembled(x);
768:   VecCheckAssembled(y);
769:   VecCheckAssembled(z);
773:   if (alpha == (PetscScalar)0.0 && beta == (PetscScalar)0.0 && gamma == (PetscScalar)1.0) PetscFunctionReturn(PETSC_SUCCESS);

775:   PetscCall(VecSetErrorIfLocked(z, 1));
776:   PetscCall(VecLockReadPush(x));
777:   PetscCall(VecLockReadPush(y));
778:   PetscCall(PetscLogEventBegin(VEC_AXPBYPCZ, x, y, z, 0));
779:   VecMethodDispatch(z, dctx, VecAsyncFnName(AXPBYPCZ), axpbypcz, (Vec, PetscScalar, PetscScalar, PetscScalar, Vec, Vec, PetscDeviceContext), alpha, beta, gamma, x, y);
780:   PetscCall(PetscLogEventEnd(VEC_AXPBYPCZ, x, y, z, 0));
781:   PetscCall(PetscObjectStateIncrease((PetscObject)z));
782:   PetscCall(VecLockReadPop(x));
783:   PetscCall(VecLockReadPop(y));
784:   PetscFunctionReturn(PETSC_SUCCESS);
785: }
786: /*@
787:   VecAXPBYPCZ - Computes `z = alpha x + beta y + gamma z`

789:   Logically Collective

791:   Input Parameters:
792: + alpha - first scalar
793: . beta  - second scalar
794: . gamma - third scalar
795: . x     - first vector
796: . y     - second vector
797: - z     - third vector

799:   Output Parameter:
800: . z - output vector

802:   Level: intermediate

804:   Note:
805:   `x`, `y` and `z` must be different vectors

807:   Developer Notes:
808:   The implementation is optimized for `alpha` of 1.0 and `gamma` of 1.0 or 0.0

810: .seealso: [](ch_vectors), `Vec`, `VecAYPX()`, `VecMAXPY()`, `VecWAXPY()`, `VecAXPY()`, `VecAXPBY()`
811: @*/
812: PetscErrorCode VecAXPBYPCZ(Vec z, PetscScalar alpha, PetscScalar beta, PetscScalar gamma, Vec x, Vec y)
813: {
814:   PetscFunctionBegin;
815:   PetscCall(VecAXPBYPCZAsync_Private(z, alpha, beta, gamma, x, y, NULL));
816:   PetscFunctionReturn(PETSC_SUCCESS);
817: }

819: PetscErrorCode VecWAXPYAsync_Private(Vec w, PetscScalar alpha, Vec x, Vec y, PetscDeviceContext dctx)
820: {
821:   PetscFunctionBegin;
828:   PetscCheckSameTypeAndComm(x, 3, y, 4);
829:   PetscCheckSameTypeAndComm(y, 4, w, 1);
830:   VecCheckSameSize(x, 3, y, 4);
831:   VecCheckSameSize(x, 3, w, 1);
832:   PetscCheck(w != y, PETSC_COMM_SELF, PETSC_ERR_SUP, "Result vector w cannot be same as input vector y, suggest VecAXPY()");
833:   PetscCheck(w != x, PETSC_COMM_SELF, PETSC_ERR_SUP, "Result vector w cannot be same as input vector x, suggest VecAYPX()");
834:   VecCheckAssembled(x);
835:   VecCheckAssembled(y);
837:   PetscCall(VecSetErrorIfLocked(w, 1));

839:   PetscCall(VecLockReadPush(x));
840:   PetscCall(VecLockReadPush(y));
841:   if (alpha == (PetscScalar)0.0) {
842:     PetscCall(VecCopyAsync_Private(y, w, dctx));
843:   } else {
844:     PetscCall(PetscLogEventBegin(VEC_WAXPY, x, y, w, 0));
845:     VecMethodDispatch(w, dctx, VecAsyncFnName(WAXPY), waxpy, (Vec, PetscScalar, Vec, Vec, PetscDeviceContext), alpha, x, y);
846:     PetscCall(PetscLogEventEnd(VEC_WAXPY, x, y, w, 0));
847:     PetscCall(PetscObjectStateIncrease((PetscObject)w));
848:   }
849:   PetscCall(VecLockReadPop(x));
850:   PetscCall(VecLockReadPop(y));
851:   PetscFunctionReturn(PETSC_SUCCESS);
852: }

854: /*@
855:   VecWAXPY - Computes `w = alpha x + y`.

857:   Logically Collective

859:   Input Parameters:
860: + alpha - the scalar
861: . x     - first vector, multiplied by `alpha`
862: - y     - second vector

864:   Output Parameter:
865: . w - the result

867:   Level: intermediate

869:   Note:
870:   `w` cannot be either `x` or `y`, but `x` and `y` can be the same

872:   Developer Notes:
873:   The implementation is optimized for alpha of -1.0, 0.0, and 1.0

875: .seealso: [](ch_vectors), `Vec`, `VecAXPY()`, `VecAYPX()`, `VecAXPBY()`, `VecMAXPY()`, `VecAXPBYPCZ()`
876: @*/
877: PetscErrorCode VecWAXPY(Vec w, PetscScalar alpha, Vec x, Vec y)
878: {
879:   PetscFunctionBegin;
880:   PetscCall(VecWAXPYAsync_Private(w, alpha, x, y, NULL));
881:   PetscFunctionReturn(PETSC_SUCCESS);
882: }

884: /*@
885:   VecSetValues - Inserts or adds values into certain locations of a vector.

887:   Not Collective

889:   Input Parameters:
890: + x    - vector to insert in
891: . ni   - number of elements to add
892: . ix   - indices where to add
893: . y    - array of values
894: - iora - either `INSERT_VALUES` to replace the current values or `ADD_VALUES` to add values to any existing entries

896:   Level: beginner

898:   Notes:
899: .vb
900:    `VecSetValues()` sets x[ix[i]] = y[i], for i=0,...,ni-1.
901: .ve

903:   Calls to `VecSetValues()` with the `INSERT_VALUES` and `ADD_VALUES`
904:   options cannot be mixed without intervening calls to the assembly
905:   routines.

907:   These values may be cached, so `VecAssemblyBegin()` and `VecAssemblyEnd()`
908:   MUST be called after all calls to `VecSetValues()` have been completed.

910:   VecSetValues() uses 0-based indices in Fortran as well as in C.

912:   If you call `VecSetOption`(x, `VEC_IGNORE_NEGATIVE_INDICES`,`PETSC_TRUE`),
913:   negative indices may be passed in ix. These rows are
914:   simply ignored. This allows easily inserting element load matrices
915:   with homogeneous Dirichlet boundary conditions that you don't want represented
916:   in the vector.

918:   Fortran Note:
919:   If any of `ix` and `y` are scalars pass them using, for example,
920: .vb
921:   call VecSetValues(mat, one, [ix], [y], INSERT_VALUES, ierr)
922: .ve

924: .seealso: [](ch_vectors), `Vec`, `VecAssemblyBegin()`, `VecAssemblyEnd()`, `VecSetValuesLocal()`,
925:           `VecSetValue()`, `VecSetValuesBlocked()`, `InsertMode`, `INSERT_VALUES`, `ADD_VALUES`, `VecGetValues()`
926: @*/
927: PetscErrorCode VecSetValues(Vec x, PetscInt ni, const PetscInt ix[], const PetscScalar y[], InsertMode iora)
928: {
929:   PetscFunctionBeginHot;
931:   if (!ni) PetscFunctionReturn(PETSC_SUCCESS);
932:   PetscAssertPointer(ix, 3);
933:   PetscAssertPointer(y, 4);

936:   PetscCall(PetscLogEventBegin(VEC_SetValues, x, 0, 0, 0));
937:   PetscUseTypeMethod(x, setvalues, ni, ix, y, iora);
938:   PetscCall(PetscLogEventEnd(VEC_SetValues, x, 0, 0, 0));
939:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
940:   PetscFunctionReturn(PETSC_SUCCESS);
941: }

943: /*@
944:   VecGetValues - Gets values from certain locations of a vector. Currently
945:   can only get values on the same processor on which they are owned

947:   Not Collective

949:   Input Parameters:
950: + x  - vector to get values from
951: . ni - number of elements to get
952: - ix - indices where to get them from (in global 1d numbering)

954:   Output Parameter:
955: . y - array of values, must be passed in with a length of `ni`

957:   Level: beginner

959:   Notes:
960:   The user provides the allocated array y; it is NOT allocated in this routine

962:   `VecGetValues()` gets y[i] = x[ix[i]], for i=0,...,ni-1.

964:   `VecAssemblyBegin()` and `VecAssemblyEnd()`  MUST be called before calling this if `VecSetValues()` or related routine has been called

966:   VecGetValues() uses 0-based indices in Fortran as well as in C.

968:   If you call `VecSetOption`(x, `VEC_IGNORE_NEGATIVE_INDICES`,`PETSC_TRUE`),
969:   negative indices may be passed in ix. These rows are
970:   simply ignored.

972: .seealso: [](ch_vectors), `Vec`, `VecAssemblyBegin()`, `VecAssemblyEnd()`, `VecSetValues()`
973: @*/
974: PetscErrorCode VecGetValues(Vec x, PetscInt ni, const PetscInt ix[], PetscScalar y[])
975: {
976:   PetscFunctionBegin;
978:   if (!ni) PetscFunctionReturn(PETSC_SUCCESS);
979:   PetscAssertPointer(ix, 3);
980:   PetscAssertPointer(y, 4);
982:   VecCheckAssembled(x);
983:   PetscUseTypeMethod(x, getvalues, ni, ix, y);
984:   PetscFunctionReturn(PETSC_SUCCESS);
985: }

987: /*@
988:   VecSetValuesBlocked - Inserts or adds blocks of values into certain locations of a vector.

990:   Not Collective

992:   Input Parameters:
993: + x    - vector to insert in
994: . ni   - number of blocks to add
995: . ix   - indices where to add in block count, rather than element count
996: . y    - array of values
997: - iora - either `INSERT_VALUES` replaces existing entries with new values, `ADD_VALUES`, adds values to any existing entries

999:   Level: intermediate

1001:   Notes:
1002:   `VecSetValuesBlocked()` sets x[bs*ix[i]+j] = y[bs*i+j],
1003:   for j=0,...,bs-1, for i=0,...,ni-1. where bs was set with VecSetBlockSize().

1005:   Calls to `VecSetValuesBlocked()` with the `INSERT_VALUES` and `ADD_VALUES`
1006:   options cannot be mixed without intervening calls to the assembly
1007:   routines.

1009:   These values may be cached, so `VecAssemblyBegin()` and `VecAssemblyEnd()`
1010:   MUST be called after all calls to `VecSetValuesBlocked()` have been completed.

1012:   `VecSetValuesBlocked()` uses 0-based indices in Fortran as well as in C.

1014:   Negative indices may be passed in ix, these rows are
1015:   simply ignored. This allows easily inserting element load matrices
1016:   with homogeneous Dirichlet boundary conditions that you don't want represented
1017:   in the vector.

1019:   Fortran Note:
1020:   If any of `ix` and `y` are scalars pass them using, for example,
1021: .vb
1022:   call VecSetValuesBlocked(mat, one, [ix], [y], INSERT_VALUES, ierr)
1023: .ve

1025: .seealso: [](ch_vectors), `Vec`, `VecAssemblyBegin()`, `VecAssemblyEnd()`, `VecSetValuesBlockedLocal()`,
1026:           `VecSetValues()`
1027: @*/
1028: PetscErrorCode VecSetValuesBlocked(Vec x, PetscInt ni, const PetscInt ix[], const PetscScalar y[], InsertMode iora)
1029: {
1030:   PetscFunctionBeginHot;
1032:   if (!ni) PetscFunctionReturn(PETSC_SUCCESS);
1033:   PetscAssertPointer(ix, 3);
1034:   PetscAssertPointer(y, 4);

1037:   PetscCall(PetscLogEventBegin(VEC_SetValues, x, 0, 0, 0));
1038:   PetscUseTypeMethod(x, setvaluesblocked, ni, ix, y, iora);
1039:   PetscCall(PetscLogEventEnd(VEC_SetValues, x, 0, 0, 0));
1040:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
1041:   PetscFunctionReturn(PETSC_SUCCESS);
1042: }

1044: /*@
1045:   VecSetValuesLocal - Inserts or adds values into certain locations of a vector,
1046:   using a local ordering of the nodes.

1048:   Not Collective

1050:   Input Parameters:
1051: + x    - vector to insert in
1052: . ni   - number of elements to add
1053: . ix   - indices where to add
1054: . y    - array of values
1055: - iora - either `INSERT_VALUES` replaces existing entries with new values, `ADD_VALUES` adds values to any existing entries

1057:   Level: intermediate

1059:   Notes:
1060:   `VecSetValuesLocal()` sets x[ix[i]] = y[i], for i=0,...,ni-1.

1062:   Calls to `VecSetValuesLocal()` with the `INSERT_VALUES` and `ADD_VALUES`
1063:   options cannot be mixed without intervening calls to the assembly
1064:   routines.

1066:   These values may be cached, so `VecAssemblyBegin()` and `VecAssemblyEnd()`
1067:   MUST be called after all calls to `VecSetValuesLocal()` have been completed.

1069:   `VecSetValuesLocal()` uses 0-based indices in Fortran as well as in C.

1071:   Fortran Note:
1072:   If any of `ix` and `y` are scalars pass them using, for example,
1073: .vb
1074:   call VecSetValuesLocal(mat, one, [ix], [y], INSERT_VALUES, ierr)
1075: .ve

1077: .seealso: [](ch_vectors), `Vec`, `VecAssemblyBegin()`, `VecAssemblyEnd()`, `VecSetValues()`, `VecSetLocalToGlobalMapping()`,
1078:           `VecSetValuesBlockedLocal()`
1079: @*/
1080: PetscErrorCode VecSetValuesLocal(Vec x, PetscInt ni, const PetscInt ix[], const PetscScalar y[], InsertMode iora)
1081: {
1082:   PetscInt lixp[128], *lix = lixp;

1084:   PetscFunctionBeginHot;
1086:   if (!ni) PetscFunctionReturn(PETSC_SUCCESS);
1087:   PetscAssertPointer(ix, 3);
1088:   PetscAssertPointer(y, 4);

1091:   PetscCall(PetscLogEventBegin(VEC_SetValues, x, 0, 0, 0));
1092:   if (!x->ops->setvalueslocal) {
1093:     if (PetscUnlikely(!x->map->mapping && x->ops->getlocaltoglobalmapping)) PetscUseTypeMethod(x, getlocaltoglobalmapping, &x->map->mapping);
1094:     if (x->map->mapping) {
1095:       if (ni > 128) PetscCall(PetscMalloc1(ni, &lix));
1096:       PetscCall(ISLocalToGlobalMappingApply(x->map->mapping, ni, (PetscInt *)ix, lix));
1097:       PetscUseTypeMethod(x, setvalues, ni, lix, y, iora);
1098:       if (ni > 128) PetscCall(PetscFree(lix));
1099:     } else PetscUseTypeMethod(x, setvalues, ni, ix, y, iora);
1100:   } else PetscUseTypeMethod(x, setvalueslocal, ni, ix, y, iora);
1101:   PetscCall(PetscLogEventEnd(VEC_SetValues, x, 0, 0, 0));
1102:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
1103:   PetscFunctionReturn(PETSC_SUCCESS);
1104: }

1106: /*@
1107:   VecSetValuesBlockedLocal - Inserts or adds values into certain locations of a vector,
1108:   using a local ordering of the nodes.

1110:   Not Collective

1112:   Input Parameters:
1113: + x    - vector to insert in
1114: . ni   - number of blocks to add
1115: . ix   - indices where to add in block count, not element count
1116: . y    - array of values
1117: - iora - either `INSERT_VALUES` replaces existing entries with new values, `ADD_VALUES` adds values to any existing entries

1119:   Level: intermediate

1121:   Notes:
1122:   `VecSetValuesBlockedLocal()` sets x[bs*ix[i]+j] = y[bs*i+j],
1123:   for j=0,..bs-1, for i=0,...,ni-1, where bs has been set with `VecSetBlockSize()`.

1125:   Calls to `VecSetValuesBlockedLocal()` with the `INSERT_VALUES` and `ADD_VALUES`
1126:   options cannot be mixed without intervening calls to the assembly
1127:   routines.

1129:   These values may be cached, so `VecAssemblyBegin()` and `VecAssemblyEnd()`
1130:   MUST be called after all calls to `VecSetValuesBlockedLocal()` have been completed.

1132:   `VecSetValuesBlockedLocal()` uses 0-based indices in Fortran as well as in C.

1134:   Fortran Note:
1135:   If any of `ix` and `y` are scalars pass them using, for example,
1136: .vb
1137:   call VecSetValuesBlockedLocal(mat, one, [ix], [y], INSERT_VALUES, ierr)
1138: .ve

1140: .seealso: [](ch_vectors), `Vec`, `VecAssemblyBegin()`, `VecAssemblyEnd()`, `VecSetValues()`, `VecSetValuesBlocked()`,
1141:           `VecSetLocalToGlobalMapping()`
1142: @*/
1143: PetscErrorCode VecSetValuesBlockedLocal(Vec x, PetscInt ni, const PetscInt ix[], const PetscScalar y[], InsertMode iora)
1144: {
1145:   PetscInt lixp[128], *lix = lixp;

1147:   PetscFunctionBeginHot;
1149:   if (!ni) PetscFunctionReturn(PETSC_SUCCESS);
1150:   PetscAssertPointer(ix, 3);
1151:   PetscAssertPointer(y, 4);
1153:   PetscCall(PetscLogEventBegin(VEC_SetValues, x, 0, 0, 0));
1154:   if (PetscUnlikely(!x->map->mapping && x->ops->getlocaltoglobalmapping)) PetscUseTypeMethod(x, getlocaltoglobalmapping, &x->map->mapping);
1155:   if (x->map->mapping) {
1156:     if (ni > 128) PetscCall(PetscMalloc1(ni, &lix));
1157:     PetscCall(ISLocalToGlobalMappingApplyBlock(x->map->mapping, ni, (PetscInt *)ix, lix));
1158:     PetscUseTypeMethod(x, setvaluesblocked, ni, lix, y, iora);
1159:     if (ni > 128) PetscCall(PetscFree(lix));
1160:   } else {
1161:     PetscUseTypeMethod(x, setvaluesblocked, ni, ix, y, iora);
1162:   }
1163:   PetscCall(PetscLogEventEnd(VEC_SetValues, x, 0, 0, 0));
1164:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
1165:   PetscFunctionReturn(PETSC_SUCCESS);
1166: }

1168: static PetscErrorCode VecMXDot_Private(Vec x, PetscInt nv, const Vec y[], PetscScalar result[], PetscErrorCode (*mxdot)(Vec, PetscInt, const Vec[], PetscScalar[]), PetscLogEvent event)
1169: {
1170:   PetscFunctionBegin;
1173:   VecCheckAssembled(x);
1175:   if (!nv) PetscFunctionReturn(PETSC_SUCCESS);
1176:   PetscAssertPointer(y, 3);
1177:   for (PetscInt i = 0; i < nv; ++i) {
1180:     PetscCheckSameTypeAndComm(x, 1, y[i], 3);
1181:     VecCheckSameSize(x, 1, y[i], 3);
1182:     VecCheckAssembled(y[i]);
1183:     PetscCall(VecLockReadPush(y[i]));
1184:   }
1185:   PetscAssertPointer(result, 4);

1188:   PetscCall(VecLockReadPush(x));
1189:   PetscCall(PetscLogEventBegin(event, x, *y, 0, 0));
1190:   PetscCall((*mxdot)(x, nv, y, result));
1191:   PetscCall(PetscLogEventEnd(event, x, *y, 0, 0));
1192:   PetscCall(VecLockReadPop(x));
1193:   for (PetscInt i = 0; i < nv; ++i) PetscCall(VecLockReadPop(y[i]));
1194:   PetscFunctionReturn(PETSC_SUCCESS);
1195: }

1197: /*@
1198:   VecMTDot - Computes indefinite vector multiple dot products.
1199:   That is, it does NOT use the complex conjugate.

1201:   Collective

1203:   Input Parameters:
1204: + x  - one vector
1205: . nv - number of vectors
1206: - y  - array of vectors.  Note that vectors are pointers

1208:   Output Parameter:
1209: . val - array of the dot products

1211:   Level: intermediate

1213:   Notes for Users of Complex Numbers:
1214:   For complex vectors, `VecMTDot()` computes the indefinite form
1215: .vb
1216:   val = (x,y) = y^T x,
1217: .ve
1218:   where y^T denotes the transpose of y.

1220:   Use `VecMDot()` for the inner product
1221: .vb
1222:   val = (x,y) = y^H x,
1223: .ve
1224:   where y^H denotes the conjugate transpose of y.

1226: .seealso: [](ch_vectors), `Vec`, `VecMDot()`, `VecTDot()`
1227: @*/
1228: PetscErrorCode VecMTDot(Vec x, PetscInt nv, const Vec y[], PetscScalar val[])
1229: {
1230:   PetscFunctionBegin;
1232:   PetscCall(VecMXDot_Private(x, nv, y, val, x->ops->mtdot, VEC_MTDot));
1233:   PetscFunctionReturn(PETSC_SUCCESS);
1234: }

1236: /*@
1237:   VecMDot - Computes multiple vector dot products.

1239:   Collective

1241:   Input Parameters:
1242: + x  - one vector
1243: . nv - number of vectors
1244: - y  - array of vectors.

1246:   Output Parameter:
1247: . val - array of the dot products (does not allocate the array)

1249:   Level: intermediate

1251:   Notes for Users of Complex Numbers:
1252:   For complex vectors, `VecMDot()` computes
1253: .vb
1254:   val = (x,y) = y^H x,
1255: .ve
1256:   where y^H denotes the conjugate transpose of y.

1258:   Use `VecMTDot()` for the indefinite form
1259: .vb
1260:   val = (x,y) = y^T x,
1261: .ve
1262:   where y^T denotes the transpose of y.

1264: .seealso: [](ch_vectors), `Vec`, `VecMTDot()`, `VecDot()`
1265: @*/
1266: PetscErrorCode VecMDot(Vec x, PetscInt nv, const Vec y[], PetscScalar val[])
1267: {
1268:   PetscFunctionBegin;
1270:   PetscCall(VecMXDot_Private(x, nv, y, val, x->ops->mdot, VEC_MDot));
1271:   PetscFunctionReturn(PETSC_SUCCESS);
1272: }

1274: PetscErrorCode VecMAXPYAsync_Private(Vec y, PetscInt nv, const PetscScalar alpha[], Vec x[], PetscDeviceContext dctx)
1275: {
1276:   PetscFunctionBegin;
1278:   VecCheckAssembled(y);
1280:   PetscCall(VecSetErrorIfLocked(y, 1));
1281:   PetscCheck(nv >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of vectors (given %" PetscInt_FMT ") cannot be negative", nv);
1282:   if (nv) {
1283:     PetscInt zeros = 0;

1285:     PetscAssertPointer(alpha, 3);
1286:     PetscAssertPointer(x, 4);
1287:     for (PetscInt i = 0; i < nv; ++i) {
1291:       PetscCheckSameTypeAndComm(y, 1, x[i], 4);
1292:       VecCheckSameSize(y, 1, x[i], 4);
1293:       PetscCheck(y != x[i], PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Array of vectors 'x' cannot contain y, found x[%" PetscInt_FMT "] == y", i);
1294:       VecCheckAssembled(x[i]);
1295:       PetscCall(VecLockReadPush(x[i]));
1296:       zeros += alpha[i] == (PetscScalar)0.0;
1297:     }

1299:     if (zeros < nv) {
1300:       PetscCall(PetscLogEventBegin(VEC_MAXPY, y, *x, 0, 0));
1301:       VecMethodDispatch(y, dctx, VecAsyncFnName(MAXPY), maxpy, (Vec, PetscInt, const PetscScalar[], Vec[], PetscDeviceContext), nv, alpha, x);
1302:       PetscCall(PetscLogEventEnd(VEC_MAXPY, y, *x, 0, 0));
1303:       PetscCall(PetscObjectStateIncrease((PetscObject)y));
1304:     }

1306:     for (PetscInt i = 0; i < nv; ++i) PetscCall(VecLockReadPop(x[i]));
1307:   }
1308:   PetscFunctionReturn(PETSC_SUCCESS);
1309: }

1311: /*@
1312:   VecMAXPY - Computes `y = y + sum alpha[i] x[i]`

1314:   Logically Collective

1316:   Input Parameters:
1317: + nv    - number of scalars and x-vectors
1318: . alpha - array of scalars
1319: . y     - one vector
1320: - x     - array of vectors

1322:   Level: intermediate

1324:   Note:
1325:   `y` cannot be any of the `x` vectors

1327: .seealso: [](ch_vectors), `Vec`, `VecMAXPBY()`,`VecAYPX()`, `VecWAXPY()`, `VecAXPY()`, `VecAXPBYPCZ()`, `VecAXPBY()`
1328: @*/
1329: PetscErrorCode VecMAXPY(Vec y, PetscInt nv, const PetscScalar alpha[], Vec x[])
1330: {
1331:   PetscFunctionBegin;
1332:   PetscCall(VecMAXPYAsync_Private(y, nv, alpha, x, NULL));
1333:   PetscFunctionReturn(PETSC_SUCCESS);
1334: }

1336: /*@
1337:   VecMAXPBY - Computes `y = beta y + sum alpha[i] x[i]`

1339:   Logically Collective

1341:   Input Parameters:
1342: + nv    - number of scalars and x-vectors
1343: . alpha - array of scalars
1344: . beta  - scalar
1345: . y     - one vector
1346: - x     - array of vectors

1348:   Level: intermediate

1350:   Note:
1351:   `y` cannot be any of the `x` vectors.

1353:   Developer Notes:
1354:   This is a convenience routine, but implementations might be able to optimize it, for example, when `beta` is zero.

1356: .seealso: [](ch_vectors), `Vec`, `VecMAXPY()`, `VecAYPX()`, `VecWAXPY()`, `VecAXPY()`, `VecAXPBYPCZ()`, `VecAXPBY()`
1357: @*/
1358: PetscErrorCode VecMAXPBY(Vec y, PetscInt nv, const PetscScalar alpha[], PetscScalar beta, Vec x[])
1359: {
1360:   PetscFunctionBegin;
1362:   VecCheckAssembled(y);
1364:   PetscCall(VecSetErrorIfLocked(y, 1));
1365:   PetscCheck(nv >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of vectors (given %" PetscInt_FMT ") cannot be negative", nv);

1368:   if (y->ops->maxpby) {
1369:     PetscInt zeros = 0;

1371:     if (nv) {
1372:       PetscAssertPointer(alpha, 3);
1373:       PetscAssertPointer(x, 5);
1374:     }

1376:     for (PetscInt i = 0; i < nv; ++i) { // scan all alpha[]
1380:       PetscCheckSameTypeAndComm(y, 1, x[i], 5);
1381:       VecCheckSameSize(y, 1, x[i], 5);
1382:       PetscCheck(y != x[i], PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Array of vectors 'x' cannot contain y, found x[%" PetscInt_FMT "] == y", i);
1383:       VecCheckAssembled(x[i]);
1384:       PetscCall(VecLockReadPush(x[i]));
1385:       zeros += alpha[i] == (PetscScalar)0.0;
1386:     }

1388:     if (zeros < nv) { // has nonzero alpha
1389:       PetscCall(PetscLogEventBegin(VEC_MAXPY, y, *x, 0, 0));
1390:       PetscUseTypeMethod(y, maxpby, nv, alpha, beta, x);
1391:       PetscCall(PetscLogEventEnd(VEC_MAXPY, y, *x, 0, 0));
1392:       PetscCall(PetscObjectStateIncrease((PetscObject)y));
1393:     } else {
1394:       PetscCall(VecScale(y, beta));
1395:     }

1397:     for (PetscInt i = 0; i < nv; ++i) PetscCall(VecLockReadPop(x[i]));
1398:   } else { // no maxpby
1399:     if (beta == 0.0) PetscCall(VecSet(y, 0.0));
1400:     else PetscCall(VecScale(y, beta));
1401:     PetscCall(VecMAXPY(y, nv, alpha, x));
1402:   }
1403:   PetscFunctionReturn(PETSC_SUCCESS);
1404: }

1406: /*@
1407:   VecConcatenate - Creates a new vector that is a vertical concatenation of all the given array of vectors
1408:   in the order they appear in the array. The concatenated vector resides on the same
1409:   communicator and is the same type as the source vectors.

1411:   Collective

1413:   Input Parameters:
1414: + nx - number of vectors to be concatenated
1415: - X  - array containing the vectors to be concatenated in the order of concatenation

1417:   Output Parameters:
1418: + Y    - concatenated vector
1419: - x_is - array of index sets corresponding to the concatenated components of `Y` (pass `NULL` if not needed)

1421:   Level: advanced

1423:   Notes:
1424:   Concatenation is similar to the functionality of a `VECNEST` object; they both represent combination of
1425:   different vector spaces. However, concatenated vectors do not store any information about their
1426:   sub-vectors and own their own data. Consequently, this function provides index sets to enable the
1427:   manipulation of data in the concatenated vector that corresponds to the original components at creation.

1429:   This is a useful tool for outer loop algorithms, particularly constrained optimizers, where the solver
1430:   has to operate on combined vector spaces and cannot utilize `VECNEST` objects due to incompatibility with
1431:   bound projections.

1433: .seealso: [](ch_vectors), `Vec`, `VECNEST`, `VECSCATTER`, `VecScatterCreate()`
1434: @*/
1435: PetscErrorCode VecConcatenate(PetscInt nx, const Vec X[], Vec *Y, IS *x_is[])
1436: {
1437:   MPI_Comm comm;
1438:   VecType  vec_type;
1439:   Vec      Ytmp, Xtmp;
1440:   IS      *is_tmp;
1441:   PetscInt i, shift = 0, Xnl, Xng, Xbegin;

1443:   PetscFunctionBegin;
1447:   PetscAssertPointer(Y, 3);

1449:   if ((*X)->ops->concatenate) {
1450:     /* use the dedicated concatenation function if available */
1451:     PetscCall((*(*X)->ops->concatenate)(nx, X, Y, x_is));
1452:   } else {
1453:     /* loop over vectors and start creating IS */
1454:     comm = PetscObjectComm((PetscObject)*X);
1455:     PetscCall(VecGetType(*X, &vec_type));
1456:     PetscCall(PetscMalloc1(nx, &is_tmp));
1457:     for (i = 0; i < nx; i++) {
1458:       PetscCall(VecGetSize(X[i], &Xng));
1459:       PetscCall(VecGetLocalSize(X[i], &Xnl));
1460:       PetscCall(VecGetOwnershipRange(X[i], &Xbegin, NULL));
1461:       PetscCall(ISCreateStride(comm, Xnl, shift + Xbegin, 1, &is_tmp[i]));
1462:       shift += Xng;
1463:     }
1464:     /* create the concatenated vector */
1465:     PetscCall(VecCreate(comm, &Ytmp));
1466:     PetscCall(VecSetType(Ytmp, vec_type));
1467:     PetscCall(VecSetSizes(Ytmp, PETSC_DECIDE, shift));
1468:     PetscCall(VecSetUp(Ytmp));
1469:     /* copy data from X array to Y and return */
1470:     for (i = 0; i < nx; i++) {
1471:       PetscCall(VecGetSubVector(Ytmp, is_tmp[i], &Xtmp));
1472:       PetscCall(VecCopy(X[i], Xtmp));
1473:       PetscCall(VecRestoreSubVector(Ytmp, is_tmp[i], &Xtmp));
1474:     }
1475:     *Y = Ytmp;
1476:     if (x_is) {
1477:       *x_is = is_tmp;
1478:     } else {
1479:       for (i = 0; i < nx; i++) PetscCall(ISDestroy(&is_tmp[i]));
1480:       PetscCall(PetscFree(is_tmp));
1481:     }
1482:   }
1483:   PetscFunctionReturn(PETSC_SUCCESS);
1484: }

1486: /* A helper function for VecGetSubVector to check if we can implement it with no-copy (i.e. the subvector shares
1487:    memory with the original vector), and the block size of the subvector.

1489:     Input Parameters:
1490: +   X - the original vector
1491: -   is - the index set of the subvector

1493:     Output Parameters:
1494: +   contig - PETSC_TRUE if the index set refers to contiguous entries on this process, else PETSC_FALSE
1495: .   start  - start of contiguous block, as an offset from the start of the ownership range of the original vector
1496: -   blocksize - the block size of the subvector

1498: */
1499: PetscErrorCode VecGetSubVectorContiguityAndBS_Private(Vec X, IS is, PetscBool *contig, PetscInt *start, PetscInt *blocksize)
1500: {
1501:   PetscInt  gstart, gend, lstart;
1502:   PetscBool red[2] = {PETSC_TRUE /*contiguous*/, PETSC_TRUE /*validVBS*/};
1503:   PetscInt  n, N, ibs, vbs, bs = 1;

1505:   PetscFunctionBegin;
1506:   PetscCall(ISGetLocalSize(is, &n));
1507:   PetscCall(ISGetSize(is, &N));
1508:   PetscCall(ISGetBlockSize(is, &ibs));
1509:   PetscCall(VecGetBlockSize(X, &vbs));
1510:   PetscCall(VecGetOwnershipRange(X, &gstart, &gend));
1511:   PetscCall(ISContiguousLocal(is, gstart, gend, &lstart, &red[0]));
1512:   /* block size is given by IS if ibs > 1; otherwise, check the vector */
1513:   if (ibs > 1) {
1514:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, red, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)is)));
1515:     bs = ibs;
1516:   } else {
1517:     if (n % vbs || vbs == 1) red[1] = PETSC_FALSE; /* this process invalidate the collectiveness of block size */
1518:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, red, 2, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)is)));
1519:     if (red[0] && red[1]) bs = vbs; /* all processes have a valid block size and the access will be contiguous */
1520:   }

1522:   *contig    = red[0];
1523:   *start     = lstart;
1524:   *blocksize = bs;
1525:   PetscFunctionReturn(PETSC_SUCCESS);
1526: }

1528: /* A helper function for VecGetSubVector, to be used when we have to build a standalone subvector through VecScatter

1530:     Input Parameters:
1531: +   X - the original vector
1532: .   is - the index set of the subvector
1533: -   bs - the block size of the subvector, gotten from VecGetSubVectorContiguityAndBS_Private()

1535:     Output Parameter:
1536: .   Z  - the subvector, which will compose the VecScatter context on output
1537: */
1538: PetscErrorCode VecGetSubVectorThroughVecScatter_Private(Vec X, IS is, PetscInt bs, Vec *Z)
1539: {
1540:   PetscInt   n, N;
1541:   VecScatter vscat;
1542:   Vec        Y;

1544:   PetscFunctionBegin;
1545:   PetscCall(ISGetLocalSize(is, &n));
1546:   PetscCall(ISGetSize(is, &N));
1547:   PetscCall(VecCreate(PetscObjectComm((PetscObject)is), &Y));
1548:   PetscCall(VecSetSizes(Y, n, N));
1549:   PetscCall(VecSetBlockSize(Y, bs));
1550:   PetscCall(VecSetType(Y, ((PetscObject)X)->type_name));
1551:   PetscCall(VecScatterCreate(X, is, Y, NULL, &vscat));
1552:   PetscCall(VecScatterBegin(vscat, X, Y, INSERT_VALUES, SCATTER_FORWARD));
1553:   PetscCall(VecScatterEnd(vscat, X, Y, INSERT_VALUES, SCATTER_FORWARD));
1554:   PetscCall(PetscObjectCompose((PetscObject)Y, "VecGetSubVector_Scatter", (PetscObject)vscat));
1555:   PetscCall(VecScatterDestroy(&vscat));
1556:   *Z = Y;
1557:   PetscFunctionReturn(PETSC_SUCCESS);
1558: }

1560: /*@
1561:   VecGetSubVector - Gets a vector representing part of another vector

1563:   Collective

1565:   Input Parameters:
1566: + X  - vector from which to extract a subvector
1567: - is - index set representing portion of `X` to extract

1569:   Output Parameter:
1570: . Y - subvector corresponding to `is`

1572:   Level: advanced

1574:   Notes:
1575:   The subvector `Y` should be returned with `VecRestoreSubVector()`.
1576:   `X` and `is` must be defined on the same communicator

1578:   Changes to the subvector will be reflected in the `X` vector on the call to `VecRestoreSubVector()`.

1580:   This function may return a subvector without making a copy, therefore it is not safe to use the original vector while
1581:   modifying the subvector.  Other non-overlapping subvectors can still be obtained from `X` using this function.

1583:   The resulting subvector inherits the block size from `is` if greater than one. Otherwise, the block size is guessed from the block size of the original `X`.

1585: .seealso: [](ch_vectors), `Vec`, `IS`, `VECNEST`, `MatCreateSubMatrix()`
1586: @*/
1587: PetscErrorCode VecGetSubVector(Vec X, IS is, Vec *Y)
1588: {
1589:   Vec Z;

1591:   PetscFunctionBegin;
1594:   PetscCheckSameComm(X, 1, is, 2);
1595:   PetscAssertPointer(Y, 3);
1596:   if (X->ops->getsubvector) {
1597:     PetscUseTypeMethod(X, getsubvector, is, &Z);
1598:   } else { /* Default implementation currently does no caching */
1599:     PetscBool contig;
1600:     PetscInt  n, N, start, bs;

1602:     PetscCall(ISGetLocalSize(is, &n));
1603:     PetscCall(ISGetSize(is, &N));
1604:     PetscCall(VecGetSubVectorContiguityAndBS_Private(X, is, &contig, &start, &bs));
1605:     if (contig) { /* We can do a no-copy implementation */
1606:       const PetscScalar *x;
1607:       PetscInt           state = 0;
1608:       PetscBool          isstd, iscuda, iship;

1610:       PetscCall(PetscObjectTypeCompareAny((PetscObject)X, &isstd, VECSEQ, VECMPI, VECSTANDARD, ""));
1611:       PetscCall(PetscObjectTypeCompareAny((PetscObject)X, &iscuda, VECSEQCUDA, VECMPICUDA, ""));
1612:       PetscCall(PetscObjectTypeCompareAny((PetscObject)X, &iship, VECSEQHIP, VECMPIHIP, ""));
1613:       if (iscuda) {
1614: #if defined(PETSC_HAVE_CUDA)
1615:         const PetscScalar *x_d;
1616:         PetscMPIInt        size;
1617:         PetscOffloadMask   flg;

1619:         PetscCall(VecCUDAGetArrays_Private(X, &x, &x_d, &flg));
1620:         PetscCheck(flg != PETSC_OFFLOAD_UNALLOCATED, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not for PETSC_OFFLOAD_UNALLOCATED");
1621:         PetscCheck(!n || x || x_d, PETSC_COMM_SELF, PETSC_ERR_SUP, "Missing vector data");
1622:         if (x) x += start;
1623:         if (x_d) x_d += start;
1624:         PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)X), &size));
1625:         if (size == 1) {
1626:           PetscCall(VecCreateSeqCUDAWithArrays(PetscObjectComm((PetscObject)X), bs, n, x, x_d, &Z));
1627:         } else {
1628:           PetscCall(VecCreateMPICUDAWithArrays(PetscObjectComm((PetscObject)X), bs, n, N, x, x_d, &Z));
1629:         }
1630:         Z->offloadmask = flg;
1631: #endif
1632:       } else if (iship) {
1633: #if defined(PETSC_HAVE_HIP)
1634:         const PetscScalar *x_d;
1635:         PetscMPIInt        size;
1636:         PetscOffloadMask   flg;

1638:         PetscCall(VecHIPGetArrays_Private(X, &x, &x_d, &flg));
1639:         PetscCheck(flg != PETSC_OFFLOAD_UNALLOCATED, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not for PETSC_OFFLOAD_UNALLOCATED");
1640:         PetscCheck(!n || x || x_d, PETSC_COMM_SELF, PETSC_ERR_SUP, "Missing vector data");
1641:         if (x) x += start;
1642:         if (x_d) x_d += start;
1643:         PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)X), &size));
1644:         if (size == 1) {
1645:           PetscCall(VecCreateSeqHIPWithArrays(PetscObjectComm((PetscObject)X), bs, n, x, x_d, &Z));
1646:         } else {
1647:           PetscCall(VecCreateMPIHIPWithArrays(PetscObjectComm((PetscObject)X), bs, n, N, x, x_d, &Z));
1648:         }
1649:         Z->offloadmask = flg;
1650: #endif
1651:       } else if (isstd) {
1652:         PetscMPIInt size;

1654:         PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)X), &size));
1655:         PetscCall(VecGetArrayRead(X, &x));
1656:         if (x) x += start;
1657:         if (size == 1) {
1658:           PetscCall(VecCreateSeqWithArray(PetscObjectComm((PetscObject)X), bs, n, x, &Z));
1659:         } else {
1660:           PetscCall(VecCreateMPIWithArray(PetscObjectComm((PetscObject)X), bs, n, N, x, &Z));
1661:         }
1662:         PetscCall(VecRestoreArrayRead(X, &x));
1663:       } else { /* default implementation: use place array */
1664:         PetscCall(VecGetArrayRead(X, &x));
1665:         PetscCall(VecCreate(PetscObjectComm((PetscObject)X), &Z));
1666:         PetscCall(VecSetType(Z, ((PetscObject)X)->type_name));
1667:         PetscCall(VecSetSizes(Z, n, N));
1668:         PetscCall(VecSetBlockSize(Z, bs));
1669:         PetscCall(VecPlaceArray(Z, PetscSafePointerPlusOffset(x, start)));
1670:         PetscCall(VecRestoreArrayRead(X, &x));
1671:       }

1673:       /* this is relevant only in debug mode */
1674:       PetscCall(VecLockGet(X, &state));
1675:       if (state) PetscCall(VecLockReadPush(Z));
1676:       Z->ops->placearray   = NULL;
1677:       Z->ops->replacearray = NULL;
1678:     } else { /* Have to create a scatter and do a copy */
1679:       PetscCall(VecGetSubVectorThroughVecScatter_Private(X, is, bs, &Z));
1680:     }
1681:   }
1682:   /* Record the state when the subvector was gotten so we know whether its values need to be put back */
1683:   if (VecGetSubVectorSavedStateId < 0) PetscCall(PetscObjectComposedDataRegister(&VecGetSubVectorSavedStateId));
1684:   PetscCall(PetscObjectComposedDataSetInt((PetscObject)Z, VecGetSubVectorSavedStateId, 1));
1685:   *Y = Z;
1686:   PetscFunctionReturn(PETSC_SUCCESS);
1687: }

1689: /*@
1690:   VecRestoreSubVector - Restores a subvector extracted using `VecGetSubVector()`

1692:   Collective

1694:   Input Parameters:
1695: + X  - vector from which subvector was obtained
1696: . is - index set representing the subset of `X`
1697: - Y  - subvector being restored

1699:   Level: advanced

1701: .seealso: [](ch_vectors), `Vec`, `IS`, `VecGetSubVector()`
1702: @*/
1703: PetscErrorCode VecRestoreSubVector(Vec X, IS is, Vec *Y)
1704: {
1705:   PETSC_UNUSED PetscObjectState dummystate = 0;
1706:   PetscBool                     unchanged;

1708:   PetscFunctionBegin;
1711:   PetscCheckSameComm(X, 1, is, 2);
1712:   PetscAssertPointer(Y, 3);

1715:   if (X->ops->restoresubvector) PetscUseTypeMethod(X, restoresubvector, is, Y);
1716:   else {
1717:     PetscCall(PetscObjectComposedDataGetInt((PetscObject)*Y, VecGetSubVectorSavedStateId, dummystate, unchanged));
1718:     if (!unchanged) { /* If Y's state has not changed since VecGetSubVector(), we only need to destroy Y */
1719:       VecScatter scatter;
1720:       PetscInt   state;

1722:       PetscCall(VecLockGet(X, &state));
1723:       PetscCheck(state == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Vec X is locked for read-only or read/write access");

1725:       PetscCall(PetscObjectQuery((PetscObject)*Y, "VecGetSubVector_Scatter", (PetscObject *)&scatter));
1726:       if (scatter) {
1727:         PetscCall(VecScatterBegin(scatter, *Y, X, INSERT_VALUES, SCATTER_REVERSE));
1728:         PetscCall(VecScatterEnd(scatter, *Y, X, INSERT_VALUES, SCATTER_REVERSE));
1729:       } else {
1730:         PetscBool iscuda, iship;
1731:         PetscCall(PetscObjectTypeCompareAny((PetscObject)X, &iscuda, VECSEQCUDA, VECMPICUDA, ""));
1732:         PetscCall(PetscObjectTypeCompareAny((PetscObject)X, &iship, VECSEQHIP, VECMPIHIP, ""));

1734:         if (iscuda) {
1735: #if defined(PETSC_HAVE_CUDA)
1736:           PetscOffloadMask ymask = (*Y)->offloadmask;

1738:           /* The offloadmask of X dictates where to move memory
1739:               If X GPU data is valid, then move Y data on GPU if needed
1740:               Otherwise, move back to the CPU */
1741:           switch (X->offloadmask) {
1742:           case PETSC_OFFLOAD_BOTH:
1743:             if (ymask == PETSC_OFFLOAD_CPU) {
1744:               PetscCall(VecCUDAResetArray(*Y));
1745:             } else if (ymask == PETSC_OFFLOAD_GPU) {
1746:               X->offloadmask = PETSC_OFFLOAD_GPU;
1747:             }
1748:             break;
1749:           case PETSC_OFFLOAD_GPU:
1750:             if (ymask == PETSC_OFFLOAD_CPU) PetscCall(VecCUDAResetArray(*Y));
1751:             break;
1752:           case PETSC_OFFLOAD_CPU:
1753:             if (ymask == PETSC_OFFLOAD_GPU) PetscCall(VecResetArray(*Y));
1754:             break;
1755:           case PETSC_OFFLOAD_UNALLOCATED:
1756:           case PETSC_OFFLOAD_KOKKOS:
1757:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_PLIB, "This should not happen");
1758:           }
1759: #endif
1760:         } else if (iship) {
1761: #if defined(PETSC_HAVE_HIP)
1762:           PetscOffloadMask ymask = (*Y)->offloadmask;

1764:           /* The offloadmask of X dictates where to move memory
1765:               If X GPU data is valid, then move Y data on GPU if needed
1766:               Otherwise, move back to the CPU */
1767:           switch (X->offloadmask) {
1768:           case PETSC_OFFLOAD_BOTH:
1769:             if (ymask == PETSC_OFFLOAD_CPU) {
1770:               PetscCall(VecHIPResetArray(*Y));
1771:             } else if (ymask == PETSC_OFFLOAD_GPU) {
1772:               X->offloadmask = PETSC_OFFLOAD_GPU;
1773:             }
1774:             break;
1775:           case PETSC_OFFLOAD_GPU:
1776:             if (ymask == PETSC_OFFLOAD_CPU) PetscCall(VecHIPResetArray(*Y));
1777:             break;
1778:           case PETSC_OFFLOAD_CPU:
1779:             if (ymask == PETSC_OFFLOAD_GPU) PetscCall(VecResetArray(*Y));
1780:             break;
1781:           case PETSC_OFFLOAD_UNALLOCATED:
1782:           case PETSC_OFFLOAD_KOKKOS:
1783:             SETERRQ(PETSC_COMM_SELF, PETSC_ERR_PLIB, "This should not happen");
1784:           }
1785: #endif
1786:         } else {
1787:           /* If OpenCL vecs updated the device memory, this triggers a copy on the CPU */
1788:           PetscCall(VecResetArray(*Y));
1789:         }
1790:         PetscCall(PetscObjectStateIncrease((PetscObject)X));
1791:       }
1792:     }
1793:   }
1794:   PetscCall(VecDestroy(Y));
1795:   PetscFunctionReturn(PETSC_SUCCESS);
1796: }

1798: /*@
1799:   VecCreateLocalVector - Creates a vector object suitable for use with `VecGetLocalVector()` and friends. You must call `VecDestroy()` when the
1800:   vector is no longer needed.

1802:   Not Collective.

1804:   Input Parameter:
1805: . v - The vector for which the local vector is desired.

1807:   Output Parameter:
1808: . w - Upon exit this contains the local vector.

1810:   Level: beginner

1812: .seealso: [](ch_vectors), `Vec`, `VecGetLocalVectorRead()`, `VecRestoreLocalVectorRead()`, `VecGetLocalVector()`, `VecRestoreLocalVector()`
1813: @*/
1814: PetscErrorCode VecCreateLocalVector(Vec v, Vec *w)
1815: {
1816:   VecType  roottype;
1817:   PetscInt n;

1819:   PetscFunctionBegin;
1821:   PetscAssertPointer(w, 2);
1822:   if (v->ops->createlocalvector) {
1823:     PetscUseTypeMethod(v, createlocalvector, w);
1824:     PetscFunctionReturn(PETSC_SUCCESS);
1825:   }
1826:   PetscCall(VecGetRootType_Private(v, &roottype));
1827:   PetscCall(VecCreate(PETSC_COMM_SELF, w));
1828:   PetscCall(VecGetLocalSize(v, &n));
1829:   PetscCall(VecSetSizes(*w, n, n));
1830:   PetscCall(VecGetBlockSize(v, &n));
1831:   PetscCall(VecSetBlockSize(*w, n));
1832:   PetscCall(VecSetType(*w, roottype));
1833:   PetscFunctionReturn(PETSC_SUCCESS);
1834: }

1836: /*@
1837:   VecGetLocalVectorRead - Maps the local portion of a vector into a
1838:   vector.

1840:   Not Collective.

1842:   Input Parameter:
1843: . v - The vector for which the local vector is desired.

1845:   Output Parameter:
1846: . w - Upon exit this contains the local vector.

1848:   Level: beginner

1850:   Notes:
1851:   You must call `VecRestoreLocalVectorRead()` when the local
1852:   vector is no longer needed.

1854:   This function is similar to `VecGetArrayRead()` which maps the local
1855:   portion into a raw pointer.  `VecGetLocalVectorRead()` is usually
1856:   almost as efficient as `VecGetArrayRead()` but in certain circumstances
1857:   `VecGetLocalVectorRead()` can be much more efficient than
1858:   `VecGetArrayRead()`.  This is because the construction of a contiguous
1859:   array representing the vector data required by `VecGetArrayRead()` can
1860:   be an expensive operation for certain vector types.  For example, for
1861:   GPU vectors `VecGetArrayRead()` requires that the data between device
1862:   and host is synchronized.

1864:   Unlike `VecGetLocalVector()`, this routine is not collective and
1865:   preserves cached information.

1867: .seealso: [](ch_vectors), `Vec`, `VecCreateLocalVector()`, `VecRestoreLocalVectorRead()`, `VecGetLocalVector()`, `VecGetArrayRead()`, `VecGetArray()`
1868: @*/
1869: PetscErrorCode VecGetLocalVectorRead(Vec v, Vec w)
1870: {
1871:   PetscFunctionBegin;
1874:   VecCheckSameLocalSize(v, 1, w, 2);
1875:   if (v->ops->getlocalvectorread) {
1876:     PetscUseTypeMethod(v, getlocalvectorread, w);
1877:   } else {
1878:     PetscScalar *a;

1880:     PetscCall(VecGetArrayRead(v, (const PetscScalar **)&a));
1881:     PetscCall(VecPlaceArray(w, a));
1882:   }
1883:   PetscCall(PetscObjectStateIncrease((PetscObject)w));
1884:   PetscCall(VecLockReadPush(v));
1885:   PetscCall(VecLockReadPush(w));
1886:   PetscFunctionReturn(PETSC_SUCCESS);
1887: }

1889: /*@
1890:   VecRestoreLocalVectorRead - Unmaps the local portion of a vector
1891:   previously mapped into a vector using `VecGetLocalVectorRead()`.

1893:   Not Collective.

1895:   Input Parameters:
1896: + v - The local portion of this vector was previously mapped into `w` using `VecGetLocalVectorRead()`.
1897: - w - The vector into which the local portion of `v` was mapped.

1899:   Level: beginner

1901: .seealso: [](ch_vectors), `Vec`, `VecCreateLocalVector()`, `VecGetLocalVectorRead()`, `VecGetLocalVector()`, `VecGetArrayRead()`, `VecGetArray()`
1902: @*/
1903: PetscErrorCode VecRestoreLocalVectorRead(Vec v, Vec w)
1904: {
1905:   PetscFunctionBegin;
1908:   if (v->ops->restorelocalvectorread) {
1909:     PetscUseTypeMethod(v, restorelocalvectorread, w);
1910:   } else {
1911:     const PetscScalar *a;

1913:     PetscCall(VecGetArrayRead(w, &a));
1914:     PetscCall(VecRestoreArrayRead(v, &a));
1915:     PetscCall(VecResetArray(w));
1916:   }
1917:   PetscCall(VecLockReadPop(v));
1918:   PetscCall(VecLockReadPop(w));
1919:   PetscCall(PetscObjectStateIncrease((PetscObject)w));
1920:   PetscFunctionReturn(PETSC_SUCCESS);
1921: }

1923: /*@
1924:   VecGetLocalVector - Maps the local portion of a vector into a
1925:   vector.

1927:   Collective

1929:   Input Parameter:
1930: . v - The vector for which the local vector is desired.

1932:   Output Parameter:
1933: . w - Upon exit this contains the local vector.

1935:   Level: beginner

1937:   Notes:
1938:   You must call `VecRestoreLocalVector()` when the local
1939:   vector is no longer needed.

1941:   This function is similar to `VecGetArray()` which maps the local
1942:   portion into a raw pointer.  `VecGetLocalVector()` is usually about as
1943:   efficient as `VecGetArray()` but in certain circumstances
1944:   `VecGetLocalVector()` can be much more efficient than `VecGetArray()`.
1945:   This is because the construction of a contiguous array representing
1946:   the vector data required by `VecGetArray()` can be an expensive
1947:   operation for certain vector types.  For example, for GPU vectors
1948:   `VecGetArray()` requires that the data between device and host is
1949:   synchronized.

1951: .seealso: [](ch_vectors), `Vec`, `VecCreateLocalVector()`, `VecRestoreLocalVector()`, `VecGetLocalVectorRead()`, `VecGetArrayRead()`, `VecGetArray()`
1952: @*/
1953: PetscErrorCode VecGetLocalVector(Vec v, Vec w)
1954: {
1955:   PetscFunctionBegin;
1958:   VecCheckSameLocalSize(v, 1, w, 2);
1959:   if (v->ops->getlocalvector) {
1960:     PetscUseTypeMethod(v, getlocalvector, w);
1961:   } else {
1962:     PetscScalar *a;

1964:     PetscCall(VecGetArray(v, &a));
1965:     PetscCall(VecPlaceArray(w, a));
1966:   }
1967:   PetscCall(PetscObjectStateIncrease((PetscObject)w));
1968:   PetscFunctionReturn(PETSC_SUCCESS);
1969: }

1971: /*@
1972:   VecRestoreLocalVector - Unmaps the local portion of a vector
1973:   previously mapped into a vector using `VecGetLocalVector()`.

1975:   Logically Collective.

1977:   Input Parameters:
1978: + v - The local portion of this vector was previously mapped into `w` using `VecGetLocalVector()`.
1979: - w - The vector into which the local portion of `v` was mapped.

1981:   Level: beginner

1983: .seealso: [](ch_vectors), `Vec`, `VecCreateLocalVector()`, `VecGetLocalVector()`, `VecGetLocalVectorRead()`, `VecRestoreLocalVectorRead()`, `LocalVectorRead()`, `VecGetArrayRead()`, `VecGetArray()`
1984: @*/
1985: PetscErrorCode VecRestoreLocalVector(Vec v, Vec w)
1986: {
1987:   PetscFunctionBegin;
1990:   if (v->ops->restorelocalvector) {
1991:     PetscUseTypeMethod(v, restorelocalvector, w);
1992:   } else {
1993:     PetscScalar *a;
1994:     PetscCall(VecGetArray(w, &a));
1995:     PetscCall(VecRestoreArray(v, &a));
1996:     PetscCall(VecResetArray(w));
1997:   }
1998:   PetscCall(PetscObjectStateIncrease((PetscObject)w));
1999:   PetscCall(PetscObjectStateIncrease((PetscObject)v));
2000:   PetscFunctionReturn(PETSC_SUCCESS);
2001: }

2003: /*@C
2004:   VecGetArray - Returns a pointer to a contiguous array that contains this
2005:   MPI processes's portion of the vector data

2007:   Logically Collective

2009:   Input Parameter:
2010: . x - the vector

2012:   Output Parameter:
2013: . a - location to put pointer to the array

2015:   Level: beginner

2017:   Notes:
2018:   For the standard PETSc vectors, `VecGetArray()` returns a pointer to the local data array and
2019:   does not use any copies. If the underlying vector data is not stored in a contiguous array
2020:   this routine will copy the data to a contiguous array and return a pointer to that. You MUST
2021:   call `VecRestoreArray()` when you no longer need access to the array.

2023:   Fortran Note:
2024: .vb
2025:   PetscScalar, pointer :: a(:)
2026: .ve

2028: .seealso: [](ch_vectors), `Vec`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecGetArrays()`, `VecPlaceArray()`, `VecGetArray2d()`,
2029:           `VecGetArrayPair()`, `VecRestoreArrayPair()`, `VecGetArrayWrite()`, `VecRestoreArrayWrite()`
2030: @*/
2031: PetscErrorCode VecGetArray(Vec x, PetscScalar *a[])
2032: {
2033:   PetscFunctionBegin;
2035:   PetscCall(VecSetErrorIfLocked(x, 1));
2036:   if (x->ops->getarray) { /* The if-else order matters! VECNEST, VECCUDA etc should have ops->getarray while VECCUDA etc are petscnative */
2037:     PetscUseTypeMethod(x, getarray, a);
2038:   } else if (x->petscnative) { /* VECSTANDARD */
2039:     *a = *((PetscScalar **)x->data);
2040:   } else SETERRQ(PetscObjectComm((PetscObject)x), PETSC_ERR_SUP, "Cannot get array for vector type \"%s\"", ((PetscObject)x)->type_name);
2041:   PetscFunctionReturn(PETSC_SUCCESS);
2042: }

2044: /*@C
2045:   VecRestoreArray - Restores a vector after `VecGetArray()` has been called and the array is no longer needed

2047:   Logically Collective

2049:   Input Parameters:
2050: + x - the vector
2051: - a - location of pointer to array obtained from `VecGetArray()`

2053:   Level: beginner

2055: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArrayRead()`, `VecRestoreArrays()`, `VecPlaceArray()`, `VecRestoreArray2d()`,
2056:           `VecGetArrayPair()`, `VecRestoreArrayPair()`
2057: @*/
2058: PetscErrorCode VecRestoreArray(Vec x, PetscScalar *a[])
2059: {
2060:   PetscFunctionBegin;
2062:   if (a) PetscAssertPointer(a, 2);
2063:   if (x->ops->restorearray) {
2064:     PetscUseTypeMethod(x, restorearray, a);
2065:   } else PetscCheck(x->petscnative, PetscObjectComm((PetscObject)x), PETSC_ERR_SUP, "Cannot restore array for vector type \"%s\"", ((PetscObject)x)->type_name);
2066:   if (a) *a = NULL;
2067:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
2068:   PetscFunctionReturn(PETSC_SUCCESS);
2069: }
2070: /*@C
2071:   VecGetArrayRead - Get read-only pointer to contiguous array containing this processor's portion of the vector data.

2073:   Not Collective

2075:   Input Parameter:
2076: . x - the vector

2078:   Output Parameter:
2079: . a - the array

2081:   Level: beginner

2083:   Notes:
2084:   The array must be returned using a matching call to `VecRestoreArrayRead()`.

2086:   Unlike `VecGetArray()`, preserves cached information like vector norms.

2088:   Standard PETSc vectors use contiguous storage so that this routine does not perform a copy.  Other vector
2089:   implementations may require a copy, but such implementations should cache the contiguous representation so that
2090:   only one copy is performed when this routine is called multiple times in sequence.

2092: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`
2093: @*/
2094: PetscErrorCode VecGetArrayRead(Vec x, const PetscScalar *a[])
2095: {
2096:   PetscFunctionBegin;
2098:   PetscAssertPointer(a, 2);
2099:   if (x->ops->getarrayread) {
2100:     PetscUseTypeMethod(x, getarrayread, a);
2101:   } else if (x->ops->getarray) {
2102:     PetscObjectState state;

2104:     /* VECNEST, VECCUDA, VECKOKKOS etc */
2105:     // x->ops->getarray may bump the object state, but since we know this is a read-only get
2106:     // we can just undo that
2107:     PetscCall(PetscObjectStateGet((PetscObject)x, &state));
2108:     PetscUseTypeMethod(x, getarray, (PetscScalar **)a);
2109:     PetscCall(PetscObjectStateSet((PetscObject)x, state));
2110:   } else if (x->petscnative) {
2111:     /* VECSTANDARD */
2112:     *a = *((PetscScalar **)x->data);
2113:   } else SETERRQ(PetscObjectComm((PetscObject)x), PETSC_ERR_SUP, "Cannot get array read for vector type \"%s\"", ((PetscObject)x)->type_name);
2114:   PetscFunctionReturn(PETSC_SUCCESS);
2115: }

2117: /*@C
2118:   VecRestoreArrayRead - Restore array obtained with `VecGetArrayRead()`

2120:   Not Collective

2122:   Input Parameters:
2123: + x - the vector
2124: - a - the array

2126:   Level: beginner

2128: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`
2129: @*/
2130: PetscErrorCode VecRestoreArrayRead(Vec x, const PetscScalar *a[])
2131: {
2132:   PetscFunctionBegin;
2134:   if (a) PetscAssertPointer(a, 2);
2135:   if (x->petscnative) { /* VECSTANDARD, VECCUDA, VECKOKKOS etc */
2136:     /* nothing */
2137:   } else if (x->ops->restorearrayread) { /* VECNEST */
2138:     PetscUseTypeMethod(x, restorearrayread, a);
2139:   } else { /* No one? */
2140:     PetscObjectState state;

2142:     // x->ops->restorearray may bump the object state, but since we know this is a read-restore
2143:     // we can just undo that
2144:     PetscCall(PetscObjectStateGet((PetscObject)x, &state));
2145:     PetscUseTypeMethod(x, restorearray, (PetscScalar **)a);
2146:     PetscCall(PetscObjectStateSet((PetscObject)x, state));
2147:   }
2148:   if (a) *a = NULL;
2149:   PetscFunctionReturn(PETSC_SUCCESS);
2150: }

2152: /*@C
2153:   VecGetArrayWrite - Returns a pointer to a contiguous array that WILL contain this
2154:   MPI processes's portion of the vector data.

2156:   Logically Collective

2158:   Input Parameter:
2159: . x - the vector

2161:   Output Parameter:
2162: . a - location to put pointer to the array

2164:   Level: intermediate

2166:   Note:
2167:   The values in this array are NOT valid, the caller of this routine is responsible for putting
2168:   values into the array; any values it does not set will be invalid.

2170:   The array must be returned using a matching call to `VecRestoreArrayWrite()`.

2172:   For vectors associated with GPUs, the host and device vectors are not synchronized before
2173:   giving access. If you need correct values in the array use `VecGetArray()`

2175: .seealso: [](ch_vectors), `Vec`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecGetArrays()`, `VecPlaceArray()`, `VecGetArray2d()`,
2176:           `VecGetArrayPair()`, `VecRestoreArrayPair()`, `VecGetArray()`, `VecRestoreArrayWrite()`
2177: @*/
2178: PetscErrorCode VecGetArrayWrite(Vec x, PetscScalar *a[])
2179: {
2180:   PetscFunctionBegin;
2182:   PetscAssertPointer(a, 2);
2183:   PetscCall(VecSetErrorIfLocked(x, 1));
2184:   if (x->ops->getarraywrite) {
2185:     PetscUseTypeMethod(x, getarraywrite, a);
2186:   } else {
2187:     PetscCall(VecGetArray(x, a));
2188:   }
2189:   PetscFunctionReturn(PETSC_SUCCESS);
2190: }

2192: /*@C
2193:   VecRestoreArrayWrite - Restores a vector after `VecGetArrayWrite()` has been called.

2195:   Logically Collective

2197:   Input Parameters:
2198: + x - the vector
2199: - a - location of pointer to array obtained from `VecGetArray()`

2201:   Level: beginner

2203: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArrayRead()`, `VecRestoreArrays()`, `VecPlaceArray()`, `VecRestoreArray2d()`,
2204:           `VecGetArrayPair()`, `VecRestoreArrayPair()`, `VecGetArrayWrite()`
2205: @*/
2206: PetscErrorCode VecRestoreArrayWrite(Vec x, PetscScalar *a[])
2207: {
2208:   PetscFunctionBegin;
2210:   if (a) PetscAssertPointer(a, 2);
2211:   if (x->ops->restorearraywrite) {
2212:     PetscUseTypeMethod(x, restorearraywrite, a);
2213:   } else if (x->ops->restorearray) {
2214:     PetscUseTypeMethod(x, restorearray, a);
2215:   }
2216:   if (a) *a = NULL;
2217:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
2218:   PetscFunctionReturn(PETSC_SUCCESS);
2219: }

2221: /*@C
2222:   VecGetArrays - Returns a pointer to the arrays in a set of vectors
2223:   that were created by a call to `VecDuplicateVecs()`.

2225:   Logically Collective; No Fortran Support

2227:   Input Parameters:
2228: + x - the vectors
2229: - n - the number of vectors

2231:   Output Parameter:
2232: . a - location to put pointer to the array

2234:   Level: intermediate

2236:   Note:
2237:   You MUST call `VecRestoreArrays()` when you no longer need access to the arrays.

2239: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArrays()`
2240: @*/
2241: PetscErrorCode VecGetArrays(const Vec x[], PetscInt n, PetscScalar **a[])
2242: {
2243:   PetscInt      i;
2244:   PetscScalar **q;

2246:   PetscFunctionBegin;
2247:   PetscAssertPointer(x, 1);
2249:   PetscAssertPointer(a, 3);
2250:   PetscCheck(n > 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Must get at least one array n = %" PetscInt_FMT, n);
2251:   PetscCall(PetscMalloc1(n, &q));
2252:   for (i = 0; i < n; ++i) PetscCall(VecGetArray(x[i], &q[i]));
2253:   *a = q;
2254:   PetscFunctionReturn(PETSC_SUCCESS);
2255: }

2257: /*@C
2258:   VecRestoreArrays - Restores a group of vectors after `VecGetArrays()`
2259:   has been called.

2261:   Logically Collective; No Fortran Support

2263:   Input Parameters:
2264: + x - the vector
2265: . n - the number of vectors
2266: - a - location of pointer to arrays obtained from `VecGetArrays()`

2268:   Notes:
2269:   For regular PETSc vectors this routine does not involve any copies. For
2270:   any special vectors that do not store local vector data in a contiguous
2271:   array, this routine will copy the data back into the underlying
2272:   vector data structure from the arrays obtained with `VecGetArrays()`.

2274:   Level: intermediate

2276: .seealso: [](ch_vectors), `Vec`, `VecGetArrays()`, `VecRestoreArray()`
2277: @*/
2278: PetscErrorCode VecRestoreArrays(const Vec x[], PetscInt n, PetscScalar **a[])
2279: {
2280:   PetscInt      i;
2281:   PetscScalar **q = *a;

2283:   PetscFunctionBegin;
2284:   PetscAssertPointer(x, 1);
2286:   PetscAssertPointer(a, 3);

2288:   for (i = 0; i < n; ++i) PetscCall(VecRestoreArray(x[i], &q[i]));
2289:   PetscCall(PetscFree(q));
2290:   PetscFunctionReturn(PETSC_SUCCESS);
2291: }

2293: /*@C
2294:   VecGetArrayAndMemType - Like `VecGetArray()`, but if this is a standard device vector (e.g.,
2295:   `VECCUDA`), the returned pointer will be a device pointer to the device memory that contains
2296:   this MPI processes's portion of the vector data.

2298:   Logically Collective; No Fortran Support

2300:   Input Parameter:
2301: . x - the vector

2303:   Output Parameters:
2304: + a     - location to put pointer to the array
2305: - mtype - memory type of the array

2307:   Level: beginner

2309:   Note:
2310:   Device data is guaranteed to have the latest value. Otherwise, when this is a host vector
2311:   (e.g., `VECMPI`), this routine functions the same as `VecGetArray()` and returns a host
2312:   pointer.

2314:   For `VECKOKKOS`, if Kokkos is configured without device (e.g., use serial or openmp), per
2315:   this function, the vector works like `VECSEQ`/`VECMPI`; otherwise, it works like `VECCUDA` or
2316:   `VECHIP` etc.

2318:   Use `VecRestoreArrayAndMemType()` when the array access is no longer needed.

2320: .seealso: [](ch_vectors), `Vec`, `VecRestoreArrayAndMemType()`, `VecGetArrayReadAndMemType()`, `VecGetArrayWriteAndMemType()`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecGetArrays()`,
2321:           `VecPlaceArray()`, `VecGetArray2d()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`, `VecGetArrayWrite()`, `VecRestoreArrayWrite()`
2322: @*/
2323: PetscErrorCode VecGetArrayAndMemType(Vec x, PetscScalar *a[], PetscMemType *mtype)
2324: {
2325:   PetscFunctionBegin;
2328:   PetscAssertPointer(a, 2);
2329:   if (mtype) PetscAssertPointer(mtype, 3);
2330:   PetscCall(VecSetErrorIfLocked(x, 1));
2331:   if (x->ops->getarrayandmemtype) {
2332:     /* VECCUDA, VECKOKKOS etc */
2333:     PetscUseTypeMethod(x, getarrayandmemtype, a, mtype);
2334:   } else {
2335:     /* VECSTANDARD, VECNEST, VECVIENNACL */
2336:     PetscCall(VecGetArray(x, a));
2337:     if (mtype) *mtype = PETSC_MEMTYPE_HOST;
2338:   }
2339:   PetscFunctionReturn(PETSC_SUCCESS);
2340: }

2342: /*@C
2343:   VecRestoreArrayAndMemType - Restores a vector after `VecGetArrayAndMemType()` has been called.

2345:   Logically Collective; No Fortran Support

2347:   Input Parameters:
2348: + x - the vector
2349: - a - location of pointer to array obtained from `VecGetArrayAndMemType()`

2351:   Level: beginner

2353: .seealso: [](ch_vectors), `Vec`, `VecGetArrayAndMemType()`, `VecGetArray()`, `VecRestoreArrayRead()`, `VecRestoreArrays()`,
2354:           `VecPlaceArray()`, `VecRestoreArray2d()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`
2355: @*/
2356: PetscErrorCode VecRestoreArrayAndMemType(Vec x, PetscScalar *a[])
2357: {
2358:   PetscFunctionBegin;
2361:   if (a) PetscAssertPointer(a, 2);
2362:   if (x->ops->restorearrayandmemtype) {
2363:     /* VECCUDA, VECKOKKOS etc */
2364:     PetscUseTypeMethod(x, restorearrayandmemtype, a);
2365:   } else {
2366:     /* VECNEST, VECVIENNACL */
2367:     PetscCall(VecRestoreArray(x, a));
2368:   } /* VECSTANDARD does nothing */
2369:   if (a) *a = NULL;
2370:   PetscCall(PetscObjectStateIncrease((PetscObject)x));
2371:   PetscFunctionReturn(PETSC_SUCCESS);
2372: }

2374: /*@C
2375:   VecGetArrayReadAndMemType - Like `VecGetArrayRead()`, but if the input vector is a device vector, it will return a read-only device pointer.
2376:   The returned pointer is guaranteed to point to up-to-date data. For host vectors, it functions as `VecGetArrayRead()`.

2378:   Not Collective; No Fortran Support

2380:   Input Parameter:
2381: . x - the vector

2383:   Output Parameters:
2384: + a     - the array
2385: - mtype - memory type of the array

2387:   Level: beginner

2389:   Notes:
2390:   The array must be returned using a matching call to `VecRestoreArrayReadAndMemType()`.

2392: .seealso: [](ch_vectors), `Vec`, `VecRestoreArrayReadAndMemType()`, `VecGetArrayAndMemType()`, `VecGetArrayWriteAndMemType()`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`
2393: @*/
2394: PetscErrorCode VecGetArrayReadAndMemType(Vec x, const PetscScalar *a[], PetscMemType *mtype)
2395: {
2396:   PetscFunctionBegin;
2399:   PetscAssertPointer(a, 2);
2400:   if (mtype) PetscAssertPointer(mtype, 3);
2401:   if (x->ops->getarrayreadandmemtype) {
2402:     /* VECCUDA/VECHIP though they are also petscnative */
2403:     PetscUseTypeMethod(x, getarrayreadandmemtype, a, mtype);
2404:   } else if (x->ops->getarrayandmemtype) {
2405:     /* VECKOKKOS */
2406:     PetscObjectState state;

2408:     // see VecGetArrayRead() for why
2409:     PetscCall(PetscObjectStateGet((PetscObject)x, &state));
2410:     PetscUseTypeMethod(x, getarrayandmemtype, (PetscScalar **)a, mtype);
2411:     PetscCall(PetscObjectStateSet((PetscObject)x, state));
2412:   } else {
2413:     PetscCall(VecGetArrayRead(x, a));
2414:     if (mtype) *mtype = PETSC_MEMTYPE_HOST;
2415:   }
2416:   PetscFunctionReturn(PETSC_SUCCESS);
2417: }

2419: /*@C
2420:   VecRestoreArrayReadAndMemType - Restore array obtained with `VecGetArrayReadAndMemType()`

2422:   Not Collective; No Fortran Support

2424:   Input Parameters:
2425: + x - the vector
2426: - a - the array

2428:   Level: beginner

2430: .seealso: [](ch_vectors), `Vec`, `VecGetArrayReadAndMemType()`, `VecRestoreArrayAndMemType()`, `VecRestoreArrayWriteAndMemType()`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`
2431: @*/
2432: PetscErrorCode VecRestoreArrayReadAndMemType(Vec x, const PetscScalar *a[])
2433: {
2434:   PetscFunctionBegin;
2437:   if (a) PetscAssertPointer(a, 2);
2438:   if (x->ops->restorearrayreadandmemtype) {
2439:     /* VECCUDA/VECHIP */
2440:     PetscUseTypeMethod(x, restorearrayreadandmemtype, a);
2441:   } else if (!x->petscnative) {
2442:     /* VECNEST */
2443:     PetscCall(VecRestoreArrayRead(x, a));
2444:   }
2445:   if (a) *a = NULL;
2446:   PetscFunctionReturn(PETSC_SUCCESS);
2447: }

2449: /*@C
2450:   VecGetArrayWriteAndMemType - Like `VecGetArrayWrite()`, but if this is a device vector it will always return
2451:   a device pointer to the device memory that contains this processor's portion of the vector data.

2453:   Logically Collective; No Fortran Support

2455:   Input Parameter:
2456: . x - the vector

2458:   Output Parameters:
2459: + a     - the array
2460: - mtype - memory type of the array

2462:   Level: beginner

2464:   Note:
2465:   The array must be returned using a matching call to `VecRestoreArrayWriteAndMemType()`, where it will label the device memory as most recent.

2467: .seealso: [](ch_vectors), `Vec`, `VecRestoreArrayWriteAndMemType()`, `VecGetArrayReadAndMemType()`, `VecGetArrayAndMemType()`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`,
2468: @*/
2469: PetscErrorCode VecGetArrayWriteAndMemType(Vec x, PetscScalar *a[], PetscMemType *mtype)
2470: {
2471:   PetscFunctionBegin;
2474:   PetscCall(VecSetErrorIfLocked(x, 1));
2475:   PetscAssertPointer(a, 2);
2476:   if (mtype) PetscAssertPointer(mtype, 3);
2477:   if (x->ops->getarraywriteandmemtype) {
2478:     /* VECCUDA, VECHIP, VECKOKKOS etc, though they are also petscnative */
2479:     PetscUseTypeMethod(x, getarraywriteandmemtype, a, mtype);
2480:   } else if (x->ops->getarrayandmemtype) {
2481:     PetscCall(VecGetArrayAndMemType(x, a, mtype));
2482:   } else {
2483:     /* VECNEST, VECVIENNACL */
2484:     PetscCall(VecGetArrayWrite(x, a));
2485:     if (mtype) *mtype = PETSC_MEMTYPE_HOST;
2486:   }
2487:   PetscFunctionReturn(PETSC_SUCCESS);
2488: }

2490: /*@C
2491:   VecRestoreArrayWriteAndMemType - Restore array obtained with `VecGetArrayWriteAndMemType()`

2493:   Logically Collective; No Fortran Support

2495:   Input Parameters:
2496: + x - the vector
2497: - a - the array

2499:   Level: beginner

2501: .seealso: [](ch_vectors), `Vec`, `VecGetArrayWriteAndMemType()`, `VecRestoreArrayAndMemType()`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrayPair()`, `VecRestoreArrayPair()`
2502: @*/
2503: PetscErrorCode VecRestoreArrayWriteAndMemType(Vec x, PetscScalar *a[])
2504: {
2505:   PetscFunctionBegin;
2508:   PetscCall(VecSetErrorIfLocked(x, 1));
2509:   if (a) PetscAssertPointer(a, 2);
2510:   if (x->ops->restorearraywriteandmemtype) {
2511:     /* VECCUDA/VECHIP */
2512:     PetscMemType PETSC_UNUSED mtype; // since this function doesn't accept a memtype?
2513:     PetscUseTypeMethod(x, restorearraywriteandmemtype, a, &mtype);
2514:   } else if (x->ops->restorearrayandmemtype) {
2515:     PetscCall(VecRestoreArrayAndMemType(x, a));
2516:   } else {
2517:     PetscCall(VecRestoreArray(x, a));
2518:   }
2519:   if (a) *a = NULL;
2520:   PetscFunctionReturn(PETSC_SUCCESS);
2521: }

2523: /*@
2524:   VecPlaceArray - Allows one to replace the array in a vector with an
2525:   array provided by the user. This is useful to avoid copying an array
2526:   into a vector.

2528:   Logically Collective; No Fortran Support

2530:   Input Parameters:
2531: + vec   - the vector
2532: - array - the array

2534:   Level: developer

2536:   Notes:
2537:   Adding `const` to `array` was an oversight, as subsequent operations on `vec` would
2538:   likely modify the data in `array`. However, we have kept it to avoid breaking APIs.

2540:   Use `VecReplaceArray()` instead to permanently replace the array

2542:   You can return to the original array with a call to `VecResetArray()`. `vec` does not take
2543:   ownership of `array` in any way.

2545:   The user must free `array` themselves but be careful not to
2546:   do so before the vector has either been destroyed, had its original array restored with
2547:   `VecResetArray()` or permanently replaced with `VecReplaceArray()`.

2549: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecReplaceArray()`, `VecResetArray()`
2550: @*/
2551: PetscErrorCode VecPlaceArray(Vec vec, const PetscScalar array[])
2552: {
2553:   PetscFunctionBegin;
2556:   if (array) PetscAssertPointer(array, 2);
2557:   PetscUseTypeMethod(vec, placearray, array);
2558:   PetscCall(PetscObjectStateIncrease((PetscObject)vec));
2559:   PetscFunctionReturn(PETSC_SUCCESS);
2560: }

2562: /*@C
2563:   VecReplaceArray - Allows one to replace the array in a vector with an
2564:   array provided by the user. This is useful to avoid copying an array
2565:   into a vector.

2567:   Logically Collective; No Fortran Support

2569:   Input Parameters:
2570: + vec   - the vector
2571: - array - the array

2573:   Level: developer

2575:   Notes:
2576:   Adding `const` to `array` was an oversight, as subsequent operations on `vec` would
2577:   likely modify the data in `array`. However, we have kept it to avoid breaking APIs.

2579:   This permanently replaces the array and frees the memory associated
2580:   with the old array. Use `VecPlaceArray()` to temporarily replace the array.

2582:   The memory passed in MUST be obtained with `PetscMalloc()` and CANNOT be
2583:   freed by the user. It will be freed when the vector is destroyed.

2585: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecPlaceArray()`, `VecResetArray()`
2586: @*/
2587: PetscErrorCode VecReplaceArray(Vec vec, const PetscScalar array[])
2588: {
2589:   PetscFunctionBegin;
2592:   PetscUseTypeMethod(vec, replacearray, array);
2593:   PetscCall(PetscObjectStateIncrease((PetscObject)vec));
2594:   PetscFunctionReturn(PETSC_SUCCESS);
2595: }

2597: /*@C
2598:   VecGetArray2d - Returns a pointer to a 2d contiguous array that contains this
2599:   processor's portion of the vector data.  You MUST call `VecRestoreArray2d()`
2600:   when you no longer need access to the array.

2602:   Logically Collective

2604:   Input Parameters:
2605: + x      - the vector
2606: . m      - first dimension of two dimensional array
2607: . n      - second dimension of two dimensional array
2608: . mstart - first index you will use in first coordinate direction (often 0)
2609: - nstart - first index in the second coordinate direction (often 0)

2611:   Output Parameter:
2612: . a - location to put pointer to the array

2614:   Level: developer

2616:   Notes:
2617:   For a vector obtained from `DMCreateLocalVector()` `mstart` and `nstart` are likely
2618:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
2619:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
2620:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray2d()`.

2622:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2624: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
2625:           `VecRestoreArray2d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
2626:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2627: @*/
2628: PetscErrorCode VecGetArray2d(Vec x, PetscInt m, PetscInt n, PetscInt mstart, PetscInt nstart, PetscScalar **a[])
2629: {
2630:   PetscInt     i, N;
2631:   PetscScalar *aa;

2633:   PetscFunctionBegin;
2635:   PetscAssertPointer(a, 6);
2637:   PetscCall(VecGetLocalSize(x, &N));
2638:   PetscCheck(m * n == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 2d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n);
2639:   PetscCall(VecGetArray(x, &aa));

2641:   PetscCall(PetscMalloc1(m, a));
2642:   for (i = 0; i < m; i++) (*a)[i] = aa + i * n - nstart;
2643:   *a -= mstart;
2644:   PetscFunctionReturn(PETSC_SUCCESS);
2645: }

2647: /*@C
2648:   VecGetArray2dWrite - Returns a pointer to a 2d contiguous array that will contain this
2649:   processor's portion of the vector data.  You MUST call `VecRestoreArray2dWrite()`
2650:   when you no longer need access to the array.

2652:   Logically Collective

2654:   Input Parameters:
2655: + x      - the vector
2656: . m      - first dimension of two dimensional array
2657: . n      - second dimension of two dimensional array
2658: . mstart - first index you will use in first coordinate direction (often 0)
2659: - nstart - first index in the second coordinate direction (often 0)

2661:   Output Parameter:
2662: . a - location to put pointer to the array

2664:   Level: developer

2666:   Notes:
2667:   For a vector obtained from `DMCreateLocalVector()` `mstart` and `nstart` are likely
2668:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
2669:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
2670:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray2d()`.

2672:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2674: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
2675:           `VecRestoreArray2d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
2676:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2677: @*/
2678: PetscErrorCode VecGetArray2dWrite(Vec x, PetscInt m, PetscInt n, PetscInt mstart, PetscInt nstart, PetscScalar **a[])
2679: {
2680:   PetscInt     i, N;
2681:   PetscScalar *aa;

2683:   PetscFunctionBegin;
2685:   PetscAssertPointer(a, 6);
2687:   PetscCall(VecGetLocalSize(x, &N));
2688:   PetscCheck(m * n == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 2d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n);
2689:   PetscCall(VecGetArrayWrite(x, &aa));

2691:   PetscCall(PetscMalloc1(m, a));
2692:   for (i = 0; i < m; i++) (*a)[i] = aa + i * n - nstart;
2693:   *a -= mstart;
2694:   PetscFunctionReturn(PETSC_SUCCESS);
2695: }

2697: /*@C
2698:   VecRestoreArray2d - Restores a vector after `VecGetArray2d()` has been called.

2700:   Logically Collective

2702:   Input Parameters:
2703: + x      - the vector
2704: . m      - first dimension of two dimensional array
2705: . n      - second dimension of the two dimensional array
2706: . mstart - first index you will use in first coordinate direction (often 0)
2707: . nstart - first index in the second coordinate direction (often 0)
2708: - a      - location of pointer to array obtained from `VecGetArray2d()`

2710:   Level: developer

2712:   Notes:
2713:   For regular PETSc vectors this routine does not involve any copies. For
2714:   any special vectors that do not store local vector data in a contiguous
2715:   array, this routine will copy the data back into the underlying
2716:   vector data structure from the array obtained with `VecGetArray()`.

2718:   This routine actually zeros out the `a` pointer.

2720: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
2721:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
2722:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2723: @*/
2724: PetscErrorCode VecRestoreArray2d(Vec x, PetscInt m, PetscInt n, PetscInt mstart, PetscInt nstart, PetscScalar **a[])
2725: {
2726:   void *dummy;

2728:   PetscFunctionBegin;
2730:   PetscAssertPointer(a, 6);
2732:   dummy = (void *)(*a + mstart);
2733:   PetscCall(PetscFree(dummy));
2734:   PetscCall(VecRestoreArray(x, NULL));
2735:   *a = NULL;
2736:   PetscFunctionReturn(PETSC_SUCCESS);
2737: }

2739: /*@C
2740:   VecRestoreArray2dWrite - Restores a vector after `VecGetArray2dWrite()` has been called.

2742:   Logically Collective

2744:   Input Parameters:
2745: + x      - the vector
2746: . m      - first dimension of two dimensional array
2747: . n      - second dimension of the two dimensional array
2748: . mstart - first index you will use in first coordinate direction (often 0)
2749: . nstart - first index in the second coordinate direction (often 0)
2750: - a      - location of pointer to array obtained from `VecGetArray2d()`

2752:   Level: developer

2754:   Notes:
2755:   For regular PETSc vectors this routine does not involve any copies. For
2756:   any special vectors that do not store local vector data in a contiguous
2757:   array, this routine will copy the data back into the underlying
2758:   vector data structure from the array obtained with `VecGetArray()`.

2760:   This routine actually zeros out the `a` pointer.

2762: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
2763:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
2764:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2765: @*/
2766: PetscErrorCode VecRestoreArray2dWrite(Vec x, PetscInt m, PetscInt n, PetscInt mstart, PetscInt nstart, PetscScalar **a[])
2767: {
2768:   void *dummy;

2770:   PetscFunctionBegin;
2772:   PetscAssertPointer(a, 6);
2774:   dummy = (void *)(*a + mstart);
2775:   PetscCall(PetscFree(dummy));
2776:   PetscCall(VecRestoreArrayWrite(x, NULL));
2777:   PetscFunctionReturn(PETSC_SUCCESS);
2778: }

2780: /*@C
2781:   VecGetArray1d - Returns a pointer to a 1d contiguous array that contains this
2782:   processor's portion of the vector data.  You MUST call `VecRestoreArray1d()`
2783:   when you no longer need access to the array.

2785:   Logically Collective

2787:   Input Parameters:
2788: + x      - the vector
2789: . m      - first dimension of two dimensional array
2790: - mstart - first index you will use in first coordinate direction (often 0)

2792:   Output Parameter:
2793: . a - location to put pointer to the array

2795:   Level: developer

2797:   Notes:
2798:   For a vector obtained from `DMCreateLocalVector()` `mstart` is likely
2799:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
2800:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`.

2802:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2804: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
2805:           `VecRestoreArray2d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
2806:           `VecGetArray2d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2807: @*/
2808: PetscErrorCode VecGetArray1d(Vec x, PetscInt m, PetscInt mstart, PetscScalar *a[])
2809: {
2810:   PetscInt N;

2812:   PetscFunctionBegin;
2814:   PetscAssertPointer(a, 4);
2816:   PetscCall(VecGetLocalSize(x, &N));
2817:   PetscCheck(m == N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local array size %" PetscInt_FMT " does not match 1d array dimensions %" PetscInt_FMT, N, m);
2818:   PetscCall(VecGetArray(x, a));
2819:   *a -= mstart;
2820:   PetscFunctionReturn(PETSC_SUCCESS);
2821: }

2823: /*@C
2824:   VecGetArray1dWrite - Returns a pointer to a 1d contiguous array that will contain this
2825:   processor's portion of the vector data.  You MUST call `VecRestoreArray1dWrite()`
2826:   when you no longer need access to the array.

2828:   Logically Collective

2830:   Input Parameters:
2831: + x      - the vector
2832: . m      - first dimension of two dimensional array
2833: - mstart - first index you will use in first coordinate direction (often 0)

2835:   Output Parameter:
2836: . a - location to put pointer to the array

2838:   Level: developer

2840:   Notes:
2841:   For a vector obtained from `DMCreateLocalVector()` `mstart` is likely
2842:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
2843:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`.

2845:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2847: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
2848:           `VecRestoreArray2d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
2849:           `VecGetArray2d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2850: @*/
2851: PetscErrorCode VecGetArray1dWrite(Vec x, PetscInt m, PetscInt mstart, PetscScalar *a[])
2852: {
2853:   PetscInt N;

2855:   PetscFunctionBegin;
2857:   PetscAssertPointer(a, 4);
2859:   PetscCall(VecGetLocalSize(x, &N));
2860:   PetscCheck(m == N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local array size %" PetscInt_FMT " does not match 1d array dimensions %" PetscInt_FMT, N, m);
2861:   PetscCall(VecGetArrayWrite(x, a));
2862:   *a -= mstart;
2863:   PetscFunctionReturn(PETSC_SUCCESS);
2864: }

2866: /*@C
2867:   VecRestoreArray1d - Restores a vector after `VecGetArray1d()` has been called.

2869:   Logically Collective

2871:   Input Parameters:
2872: + x      - the vector
2873: . m      - first dimension of two dimensional array
2874: . mstart - first index you will use in first coordinate direction (often 0)
2875: - a      - location of pointer to array obtained from `VecGetArray1d()`

2877:   Level: developer

2879:   Notes:
2880:   For regular PETSc vectors this routine does not involve any copies. For
2881:   any special vectors that do not store local vector data in a contiguous
2882:   array, this routine will copy the data back into the underlying
2883:   vector data structure from the array obtained with `VecGetArray1d()`.

2885:   This routine actually zeros out the `a` pointer.

2887: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
2888:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
2889:           `VecGetArray1d()`, `VecRestoreArray2d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2890: @*/
2891: PetscErrorCode VecRestoreArray1d(Vec x, PetscInt m, PetscInt mstart, PetscScalar *a[])
2892: {
2893:   PetscFunctionBegin;
2896:   PetscCall(VecRestoreArray(x, NULL));
2897:   *a = NULL;
2898:   PetscFunctionReturn(PETSC_SUCCESS);
2899: }

2901: /*@C
2902:   VecRestoreArray1dWrite - Restores a vector after `VecGetArray1dWrite()` has been called.

2904:   Logically Collective

2906:   Input Parameters:
2907: + x      - the vector
2908: . m      - first dimension of two dimensional array
2909: . mstart - first index you will use in first coordinate direction (often 0)
2910: - a      - location of pointer to array obtained from `VecGetArray1d()`

2912:   Level: developer

2914:   Notes:
2915:   For regular PETSc vectors this routine does not involve any copies. For
2916:   any special vectors that do not store local vector data in a contiguous
2917:   array, this routine will copy the data back into the underlying
2918:   vector data structure from the array obtained with `VecGetArray1d()`.

2920:   This routine actually zeros out the `a` pointer.

2922: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
2923:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
2924:           `VecGetArray1d()`, `VecRestoreArray2d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2925: @*/
2926: PetscErrorCode VecRestoreArray1dWrite(Vec x, PetscInt m, PetscInt mstart, PetscScalar *a[])
2927: {
2928:   PetscFunctionBegin;
2931:   PetscCall(VecRestoreArrayWrite(x, NULL));
2932:   *a = NULL;
2933:   PetscFunctionReturn(PETSC_SUCCESS);
2934: }

2936: /*@C
2937:   VecGetArray3d - Returns a pointer to a 3d contiguous array that contains this
2938:   processor's portion of the vector data.  You MUST call `VecRestoreArray3d()`
2939:   when you no longer need access to the array.

2941:   Logically Collective

2943:   Input Parameters:
2944: + x      - the vector
2945: . m      - first dimension of three dimensional array
2946: . n      - second dimension of three dimensional array
2947: . p      - third dimension of three dimensional array
2948: . mstart - first index you will use in first coordinate direction (often 0)
2949: . nstart - first index in the second coordinate direction (often 0)
2950: - pstart - first index in the third coordinate direction (often 0)

2952:   Output Parameter:
2953: . a - location to put pointer to the array

2955:   Level: developer

2957:   Notes:
2958:   For a vector obtained from `DMCreateLocalVector()` `mstart`, `nstart`, and `pstart` are likely
2959:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
2960:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
2961:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray3d()`.

2963:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2965: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
2966:           `VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecRestoreArray3d()`,
2967:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
2968: @*/
2969: PetscErrorCode VecGetArray3d(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscScalar ***a[])
2970: {
2971:   PetscInt     i, N, j;
2972:   PetscScalar *aa, **b;

2974:   PetscFunctionBegin;
2976:   PetscAssertPointer(a, 8);
2978:   PetscCall(VecGetLocalSize(x, &N));
2979:   PetscCheck(m * n * p == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 3d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n, p);
2980:   PetscCall(VecGetArray(x, &aa));

2982:   PetscCall(PetscMalloc(m * sizeof(PetscScalar **) + m * n * sizeof(PetscScalar *), a));
2983:   b = (PetscScalar **)((*a) + m);
2984:   for (i = 0; i < m; i++) (*a)[i] = b + i * n - nstart;
2985:   for (i = 0; i < m; i++)
2986:     for (j = 0; j < n; j++) b[i * n + j] = PetscSafePointerPlusOffset(aa, i * n * p + j * p - pstart);
2987:   *a -= mstart;
2988:   PetscFunctionReturn(PETSC_SUCCESS);
2989: }

2991: /*@C
2992:   VecGetArray3dWrite - Returns a pointer to a 3d contiguous array that will contain this
2993:   processor's portion of the vector data.  You MUST call `VecRestoreArray3dWrite()`
2994:   when you no longer need access to the array.

2996:   Logically Collective

2998:   Input Parameters:
2999: + x      - the vector
3000: . m      - first dimension of three dimensional array
3001: . n      - second dimension of three dimensional array
3002: . p      - third dimension of three dimensional array
3003: . mstart - first index you will use in first coordinate direction (often 0)
3004: . nstart - first index in the second coordinate direction (often 0)
3005: - pstart - first index in the third coordinate direction (often 0)

3007:   Output Parameter:
3008: . a - location to put pointer to the array

3010:   Level: developer

3012:   Notes:
3013:   For a vector obtained from `DMCreateLocalVector()` `mstart`, `nstart`, and `pstart` are likely
3014:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3015:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
3016:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray3d()`.

3018:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3020: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3021:           `VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3022:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3023: @*/
3024: PetscErrorCode VecGetArray3dWrite(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscScalar ***a[])
3025: {
3026:   PetscInt     i, N, j;
3027:   PetscScalar *aa, **b;

3029:   PetscFunctionBegin;
3031:   PetscAssertPointer(a, 8);
3033:   PetscCall(VecGetLocalSize(x, &N));
3034:   PetscCheck(m * n * p == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 3d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n, p);
3035:   PetscCall(VecGetArrayWrite(x, &aa));

3037:   PetscCall(PetscMalloc(m * sizeof(PetscScalar **) + m * n * sizeof(PetscScalar *), a));
3038:   b = (PetscScalar **)((*a) + m);
3039:   for (i = 0; i < m; i++) (*a)[i] = b + i * n - nstart;
3040:   for (i = 0; i < m; i++)
3041:     for (j = 0; j < n; j++) b[i * n + j] = aa + i * n * p + j * p - pstart;

3043:   *a -= mstart;
3044:   PetscFunctionReturn(PETSC_SUCCESS);
3045: }

3047: /*@C
3048:   VecRestoreArray3d - Restores a vector after `VecGetArray3d()` has been called.

3050:   Logically Collective

3052:   Input Parameters:
3053: + x      - the vector
3054: . m      - first dimension of three dimensional array
3055: . n      - second dimension of the three dimensional array
3056: . p      - third dimension of the three dimensional array
3057: . mstart - first index you will use in first coordinate direction (often 0)
3058: . nstart - first index in the second coordinate direction (often 0)
3059: . pstart - first index in the third coordinate direction (often 0)
3060: - a      - location of pointer to array obtained from VecGetArray3d()

3062:   Level: developer

3064:   Notes:
3065:   For regular PETSc vectors this routine does not involve any copies. For
3066:   any special vectors that do not store local vector data in a contiguous
3067:   array, this routine will copy the data back into the underlying
3068:   vector data structure from the array obtained with `VecGetArray()`.

3070:   This routine actually zeros out the `a` pointer.

3072: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3073:           `VecGetArray2d()`, `VecGetArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3074:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3075: @*/
3076: PetscErrorCode VecRestoreArray3d(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscScalar ***a[])
3077: {
3078:   void *dummy;

3080:   PetscFunctionBegin;
3082:   PetscAssertPointer(a, 8);
3084:   dummy = (void *)(*a + mstart);
3085:   PetscCall(PetscFree(dummy));
3086:   PetscCall(VecRestoreArray(x, NULL));
3087:   *a = NULL;
3088:   PetscFunctionReturn(PETSC_SUCCESS);
3089: }

3091: /*@C
3092:   VecRestoreArray3dWrite - Restores a vector after `VecGetArray3dWrite()` has been called.

3094:   Logically Collective

3096:   Input Parameters:
3097: + x      - the vector
3098: . m      - first dimension of three dimensional array
3099: . n      - second dimension of the three dimensional array
3100: . p      - third dimension of the three dimensional array
3101: . mstart - first index you will use in first coordinate direction (often 0)
3102: . nstart - first index in the second coordinate direction (often 0)
3103: . pstart - first index in the third coordinate direction (often 0)
3104: - a      - location of pointer to array obtained from VecGetArray3d()

3106:   Level: developer

3108:   Notes:
3109:   For regular PETSc vectors this routine does not involve any copies. For
3110:   any special vectors that do not store local vector data in a contiguous
3111:   array, this routine will copy the data back into the underlying
3112:   vector data structure from the array obtained with `VecGetArray()`.

3114:   This routine actually zeros out the `a` pointer.

3116: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3117:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3118:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3119: @*/
3120: PetscErrorCode VecRestoreArray3dWrite(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscScalar ***a[])
3121: {
3122:   void *dummy;

3124:   PetscFunctionBegin;
3126:   PetscAssertPointer(a, 8);
3128:   dummy = (void *)(*a + mstart);
3129:   PetscCall(PetscFree(dummy));
3130:   PetscCall(VecRestoreArrayWrite(x, NULL));
3131:   *a = NULL;
3132:   PetscFunctionReturn(PETSC_SUCCESS);
3133: }

3135: /*@C
3136:   VecGetArray4d - Returns a pointer to a 4d contiguous array that contains this
3137:   processor's portion of the vector data.  You MUST call `VecRestoreArray4d()`
3138:   when you no longer need access to the array.

3140:   Logically Collective

3142:   Input Parameters:
3143: + x      - the vector
3144: . m      - first dimension of four dimensional array
3145: . n      - second dimension of four dimensional array
3146: . p      - third dimension of four dimensional array
3147: . q      - fourth dimension of four dimensional array
3148: . mstart - first index you will use in first coordinate direction (often 0)
3149: . nstart - first index in the second coordinate direction (often 0)
3150: . pstart - first index in the third coordinate direction (often 0)
3151: - qstart - first index in the fourth coordinate direction (often 0)

3153:   Output Parameter:
3154: . a - location to put pointer to the array

3156:   Level: developer

3158:   Notes:
3159:   For a vector obtained from `DMCreateLocalVector()` `mstart`, `nstart`, and `pstart` are likely
3160:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3161:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
3162:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray3d()`.

3164:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3166: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3167:           `VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3168:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecRestoreArray4d()`
3169: @*/
3170: PetscErrorCode VecGetArray4d(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
3171: {
3172:   PetscInt     i, N, j, k;
3173:   PetscScalar *aa, ***b, **c;

3175:   PetscFunctionBegin;
3177:   PetscAssertPointer(a, 10);
3179:   PetscCall(VecGetLocalSize(x, &N));
3180:   PetscCheck(m * n * p * q == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 4d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n, p, q);
3181:   PetscCall(VecGetArray(x, &aa));

3183:   PetscCall(PetscMalloc(m * sizeof(PetscScalar ***) + m * n * sizeof(PetscScalar **) + m * n * p * sizeof(PetscScalar *), a));
3184:   b = (PetscScalar ***)((*a) + m);
3185:   c = (PetscScalar **)(b + m * n);
3186:   for (i = 0; i < m; i++) (*a)[i] = b + i * n - nstart;
3187:   for (i = 0; i < m; i++)
3188:     for (j = 0; j < n; j++) b[i * n + j] = c + i * n * p + j * p - pstart;
3189:   for (i = 0; i < m; i++)
3190:     for (j = 0; j < n; j++)
3191:       for (k = 0; k < p; k++) c[i * n * p + j * p + k] = aa + i * n * p * q + j * p * q + k * q - qstart;
3192:   *a -= mstart;
3193:   PetscFunctionReturn(PETSC_SUCCESS);
3194: }

3196: /*@C
3197:   VecGetArray4dWrite - Returns a pointer to a 4d contiguous array that will contain this
3198:   processor's portion of the vector data.  You MUST call `VecRestoreArray4dWrite()`
3199:   when you no longer need access to the array.

3201:   Logically Collective

3203:   Input Parameters:
3204: + x      - the vector
3205: . m      - first dimension of four dimensional array
3206: . n      - second dimension of four dimensional array
3207: . p      - third dimension of four dimensional array
3208: . q      - fourth dimension of four dimensional array
3209: . mstart - first index you will use in first coordinate direction (often 0)
3210: . nstart - first index in the second coordinate direction (often 0)
3211: . pstart - first index in the third coordinate direction (often 0)
3212: - qstart - first index in the fourth coordinate direction (often 0)

3214:   Output Parameter:
3215: . a - location to put pointer to the array

3217:   Level: developer

3219:   Notes:
3220:   For a vector obtained from `DMCreateLocalVector()` `mstart`, `nstart`, and `pstart` are likely
3221:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3222:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
3223:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray3d()`.

3225:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3227: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3228:           `VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3229:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3230: @*/
3231: PetscErrorCode VecGetArray4dWrite(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
3232: {
3233:   PetscInt     i, N, j, k;
3234:   PetscScalar *aa, ***b, **c;

3236:   PetscFunctionBegin;
3238:   PetscAssertPointer(a, 10);
3240:   PetscCall(VecGetLocalSize(x, &N));
3241:   PetscCheck(m * n * p * q == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 4d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n, p, q);
3242:   PetscCall(VecGetArrayWrite(x, &aa));

3244:   PetscCall(PetscMalloc(m * sizeof(PetscScalar ***) + m * n * sizeof(PetscScalar **) + m * n * p * sizeof(PetscScalar *), a));
3245:   b = (PetscScalar ***)((*a) + m);
3246:   c = (PetscScalar **)(b + m * n);
3247:   for (i = 0; i < m; i++) (*a)[i] = b + i * n - nstart;
3248:   for (i = 0; i < m; i++)
3249:     for (j = 0; j < n; j++) b[i * n + j] = c + i * n * p + j * p - pstart;
3250:   for (i = 0; i < m; i++)
3251:     for (j = 0; j < n; j++)
3252:       for (k = 0; k < p; k++) c[i * n * p + j * p + k] = aa + i * n * p * q + j * p * q + k * q - qstart;
3253:   *a -= mstart;
3254:   PetscFunctionReturn(PETSC_SUCCESS);
3255: }

3257: /*@C
3258:   VecRestoreArray4d - Restores a vector after `VecGetArray4d()` has been called.

3260:   Logically Collective

3262:   Input Parameters:
3263: + x      - the vector
3264: . m      - first dimension of four dimensional array
3265: . n      - second dimension of the four dimensional array
3266: . p      - third dimension of the four dimensional array
3267: . q      - fourth dimension of the four dimensional array
3268: . mstart - first index you will use in first coordinate direction (often 0)
3269: . nstart - first index in the second coordinate direction (often 0)
3270: . pstart - first index in the third coordinate direction (often 0)
3271: . qstart - first index in the fourth coordinate direction (often 0)
3272: - a      - location of pointer to array obtained from VecGetArray4d()

3274:   Level: developer

3276:   Notes:
3277:   For regular PETSc vectors this routine does not involve any copies. For
3278:   any special vectors that do not store local vector data in a contiguous
3279:   array, this routine will copy the data back into the underlying
3280:   vector data structure from the array obtained with `VecGetArray()`.

3282:   This routine actually zeros out the `a` pointer.

3284: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3285:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3286:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`
3287: @*/
3288: PetscErrorCode VecRestoreArray4d(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
3289: {
3290:   void *dummy;

3292:   PetscFunctionBegin;
3294:   PetscAssertPointer(a, 10);
3296:   dummy = (void *)(*a + mstart);
3297:   PetscCall(PetscFree(dummy));
3298:   PetscCall(VecRestoreArray(x, NULL));
3299:   *a = NULL;
3300:   PetscFunctionReturn(PETSC_SUCCESS);
3301: }

3303: /*@C
3304:   VecRestoreArray4dWrite - Restores a vector after `VecGetArray4dWrite()` has been called.

3306:   Logically Collective

3308:   Input Parameters:
3309: + x      - the vector
3310: . m      - first dimension of four dimensional array
3311: . n      - second dimension of the four dimensional array
3312: . p      - third dimension of the four dimensional array
3313: . q      - fourth dimension of the four dimensional array
3314: . mstart - first index you will use in first coordinate direction (often 0)
3315: . nstart - first index in the second coordinate direction (often 0)
3316: . pstart - first index in the third coordinate direction (often 0)
3317: . qstart - first index in the fourth coordinate direction (often 0)
3318: - a      - location of pointer to array obtained from `VecGetArray4d()`

3320:   Level: developer

3322:   Notes:
3323:   For regular PETSc vectors this routine does not involve any copies. For
3324:   any special vectors that do not store local vector data in a contiguous
3325:   array, this routine will copy the data back into the underlying
3326:   vector data structure from the array obtained with `VecGetArray()`.

3328:   This routine actually zeros out the `a` pointer.

3330: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3331:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3332:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3333: @*/
3334: PetscErrorCode VecRestoreArray4dWrite(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
3335: {
3336:   void *dummy;

3338:   PetscFunctionBegin;
3340:   PetscAssertPointer(a, 10);
3342:   dummy = (void *)(*a + mstart);
3343:   PetscCall(PetscFree(dummy));
3344:   PetscCall(VecRestoreArrayWrite(x, NULL));
3345:   *a = NULL;
3346:   PetscFunctionReturn(PETSC_SUCCESS);
3347: }

3349: /*@C
3350:   VecGetArray2dRead - Returns a pointer to a 2d contiguous array that contains this
3351:   processor's portion of the vector data.  You MUST call `VecRestoreArray2dRead()`
3352:   when you no longer need access to the array.

3354:   Logically Collective

3356:   Input Parameters:
3357: + x      - the vector
3358: . m      - first dimension of two dimensional array
3359: . n      - second dimension of two dimensional array
3360: . mstart - first index you will use in first coordinate direction (often 0)
3361: - nstart - first index in the second coordinate direction (often 0)

3363:   Output Parameter:
3364: . a - location to put pointer to the array

3366:   Level: developer

3368:   Notes:
3369:   For a vector obtained from `DMCreateLocalVector()` `mstart` and `nstart` are likely
3370:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3371:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
3372:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray2d()`.

3374:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3376: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3377:           `VecRestoreArray2d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3378:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3379: @*/
3380: PetscErrorCode VecGetArray2dRead(Vec x, PetscInt m, PetscInt n, PetscInt mstart, PetscInt nstart, PetscScalar **a[])
3381: {
3382:   PetscInt           i, N;
3383:   const PetscScalar *aa;

3385:   PetscFunctionBegin;
3387:   PetscAssertPointer(a, 6);
3389:   PetscCall(VecGetLocalSize(x, &N));
3390:   PetscCheck(m * n == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 2d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n);
3391:   PetscCall(VecGetArrayRead(x, &aa));

3393:   PetscCall(PetscMalloc1(m, a));
3394:   for (i = 0; i < m; i++) (*a)[i] = (PetscScalar *)aa + i * n - nstart;
3395:   *a -= mstart;
3396:   PetscFunctionReturn(PETSC_SUCCESS);
3397: }

3399: /*@C
3400:   VecRestoreArray2dRead - Restores a vector after `VecGetArray2dRead()` has been called.

3402:   Logically Collective

3404:   Input Parameters:
3405: + x      - the vector
3406: . m      - first dimension of two dimensional array
3407: . n      - second dimension of the two dimensional array
3408: . mstart - first index you will use in first coordinate direction (often 0)
3409: . nstart - first index in the second coordinate direction (often 0)
3410: - a      - location of pointer to array obtained from VecGetArray2d()

3412:   Level: developer

3414:   Notes:
3415:   For regular PETSc vectors this routine does not involve any copies. For
3416:   any special vectors that do not store local vector data in a contiguous
3417:   array, this routine will copy the data back into the underlying
3418:   vector data structure from the array obtained with `VecGetArray()`.

3420:   This routine actually zeros out the `a` pointer.

3422: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3423:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3424:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3425: @*/
3426: PetscErrorCode VecRestoreArray2dRead(Vec x, PetscInt m, PetscInt n, PetscInt mstart, PetscInt nstart, PetscScalar **a[])
3427: {
3428:   void *dummy;

3430:   PetscFunctionBegin;
3432:   PetscAssertPointer(a, 6);
3434:   dummy = (void *)(*a + mstart);
3435:   PetscCall(PetscFree(dummy));
3436:   PetscCall(VecRestoreArrayRead(x, NULL));
3437:   *a = NULL;
3438:   PetscFunctionReturn(PETSC_SUCCESS);
3439: }

3441: /*@C
3442:   VecGetArray1dRead - Returns a pointer to a 1d contiguous array that contains this
3443:   processor's portion of the vector data.  You MUST call `VecRestoreArray1dRead()`
3444:   when you no longer need access to the array.

3446:   Logically Collective

3448:   Input Parameters:
3449: + x      - the vector
3450: . m      - first dimension of two dimensional array
3451: - mstart - first index you will use in first coordinate direction (often 0)

3453:   Output Parameter:
3454: . a - location to put pointer to the array

3456:   Level: developer

3458:   Notes:
3459:   For a vector obtained from `DMCreateLocalVector()` `mstart` is likely
3460:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3461:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`.

3463:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3465: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3466:           `VecRestoreArray2d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3467:           `VecGetArray2d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3468: @*/
3469: PetscErrorCode VecGetArray1dRead(Vec x, PetscInt m, PetscInt mstart, PetscScalar *a[])
3470: {
3471:   PetscInt N;

3473:   PetscFunctionBegin;
3475:   PetscAssertPointer(a, 4);
3477:   PetscCall(VecGetLocalSize(x, &N));
3478:   PetscCheck(m == N, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Local array size %" PetscInt_FMT " does not match 1d array dimensions %" PetscInt_FMT, N, m);
3479:   PetscCall(VecGetArrayRead(x, (const PetscScalar **)a));
3480:   *a -= mstart;
3481:   PetscFunctionReturn(PETSC_SUCCESS);
3482: }

3484: /*@C
3485:   VecRestoreArray1dRead - Restores a vector after `VecGetArray1dRead()` has been called.

3487:   Logically Collective

3489:   Input Parameters:
3490: + x      - the vector
3491: . m      - first dimension of two dimensional array
3492: . mstart - first index you will use in first coordinate direction (often 0)
3493: - a      - location of pointer to array obtained from `VecGetArray1dRead()`

3495:   Level: developer

3497:   Notes:
3498:   For regular PETSc vectors this routine does not involve any copies. For
3499:   any special vectors that do not store local vector data in a contiguous
3500:   array, this routine will copy the data back into the underlying
3501:   vector data structure from the array obtained with `VecGetArray1dRead()`.

3503:   This routine actually zeros out the `a` pointer.

3505: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3506:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3507:           `VecGetArray1d()`, `VecRestoreArray2d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3508: @*/
3509: PetscErrorCode VecRestoreArray1dRead(Vec x, PetscInt m, PetscInt mstart, PetscScalar *a[])
3510: {
3511:   PetscFunctionBegin;
3514:   PetscCall(VecRestoreArrayRead(x, NULL));
3515:   *a = NULL;
3516:   PetscFunctionReturn(PETSC_SUCCESS);
3517: }

3519: /*@C
3520:   VecGetArray3dRead - Returns a pointer to a 3d contiguous array that contains this
3521:   processor's portion of the vector data.  You MUST call `VecRestoreArray3dRead()`
3522:   when you no longer need access to the array.

3524:   Logically Collective

3526:   Input Parameters:
3527: + x      - the vector
3528: . m      - first dimension of three dimensional array
3529: . n      - second dimension of three dimensional array
3530: . p      - third dimension of three dimensional array
3531: . mstart - first index you will use in first coordinate direction (often 0)
3532: . nstart - first index in the second coordinate direction (often 0)
3533: - pstart - first index in the third coordinate direction (often 0)

3535:   Output Parameter:
3536: . a - location to put pointer to the array

3538:   Level: developer

3540:   Notes:
3541:   For a vector obtained from `DMCreateLocalVector()` `mstart`, `nstart`, and `pstart` are likely
3542:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3543:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
3544:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray3dRead()`.

3546:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3548: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3549:           `VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3550:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3551: @*/
3552: PetscErrorCode VecGetArray3dRead(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscScalar ***a[])
3553: {
3554:   PetscInt           i, N, j;
3555:   const PetscScalar *aa;
3556:   PetscScalar      **b;

3558:   PetscFunctionBegin;
3560:   PetscAssertPointer(a, 8);
3562:   PetscCall(VecGetLocalSize(x, &N));
3563:   PetscCheck(m * n * p == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 3d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n, p);
3564:   PetscCall(VecGetArrayRead(x, &aa));

3566:   PetscCall(PetscMalloc(m * sizeof(PetscScalar **) + m * n * sizeof(PetscScalar *), a));
3567:   b = (PetscScalar **)((*a) + m);
3568:   for (i = 0; i < m; i++) (*a)[i] = b + i * n - nstart;
3569:   for (i = 0; i < m; i++)
3570:     for (j = 0; j < n; j++) b[i * n + j] = PetscSafePointerPlusOffset((PetscScalar *)aa, i * n * p + j * p - pstart);
3571:   *a -= mstart;
3572:   PetscFunctionReturn(PETSC_SUCCESS);
3573: }

3575: /*@C
3576:   VecRestoreArray3dRead - Restores a vector after `VecGetArray3dRead()` has been called.

3578:   Logically Collective

3580:   Input Parameters:
3581: + x      - the vector
3582: . m      - first dimension of three dimensional array
3583: . n      - second dimension of the three dimensional array
3584: . p      - third dimension of the three dimensional array
3585: . mstart - first index you will use in first coordinate direction (often 0)
3586: . nstart - first index in the second coordinate direction (often 0)
3587: . pstart - first index in the third coordinate direction (often 0)
3588: - a      - location of pointer to array obtained from `VecGetArray3dRead()`

3590:   Level: developer

3592:   Notes:
3593:   For regular PETSc vectors this routine does not involve any copies. For
3594:   any special vectors that do not store local vector data in a contiguous
3595:   array, this routine will copy the data back into the underlying
3596:   vector data structure from the array obtained with `VecGetArray()`.

3598:   This routine actually zeros out the `a` pointer.

3600: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3601:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3602:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3603: @*/
3604: PetscErrorCode VecRestoreArray3dRead(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscScalar ***a[])
3605: {
3606:   void *dummy;

3608:   PetscFunctionBegin;
3610:   PetscAssertPointer(a, 8);
3612:   dummy = (void *)(*a + mstart);
3613:   PetscCall(PetscFree(dummy));
3614:   PetscCall(VecRestoreArrayRead(x, NULL));
3615:   *a = NULL;
3616:   PetscFunctionReturn(PETSC_SUCCESS);
3617: }

3619: /*@C
3620:   VecGetArray4dRead - Returns a pointer to a 4d contiguous array that contains this
3621:   processor's portion of the vector data.  You MUST call `VecRestoreArray4dRead()`
3622:   when you no longer need access to the array.

3624:   Logically Collective

3626:   Input Parameters:
3627: + x      - the vector
3628: . m      - first dimension of four dimensional array
3629: . n      - second dimension of four dimensional array
3630: . p      - third dimension of four dimensional array
3631: . q      - fourth dimension of four dimensional array
3632: . mstart - first index you will use in first coordinate direction (often 0)
3633: . nstart - first index in the second coordinate direction (often 0)
3634: . pstart - first index in the third coordinate direction (often 0)
3635: - qstart - first index in the fourth coordinate direction (often 0)

3637:   Output Parameter:
3638: . a - location to put pointer to the array

3640:   Level: beginner

3642:   Notes:
3643:   For a vector obtained from `DMCreateLocalVector()` `mstart`, `nstart`, and `pstart` are likely
3644:   obtained from the corner indices obtained from `DMDAGetGhostCorners()` while for
3645:   `DMCreateGlobalVector()` they are the corner indices from `DMDAGetCorners()`. In both cases
3646:   the arguments from `DMDAGet[Ghost]Corners()` are reversed in the call to `VecGetArray3d()`.

3648:   For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

3650: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecPlaceArray()`,
3651:           `VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
3652:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3653: @*/
3654: PetscErrorCode VecGetArray4dRead(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
3655: {
3656:   PetscInt           i, N, j, k;
3657:   const PetscScalar *aa;
3658:   PetscScalar     ***b, **c;

3660:   PetscFunctionBegin;
3662:   PetscAssertPointer(a, 10);
3664:   PetscCall(VecGetLocalSize(x, &N));
3665:   PetscCheck(m * n * p * q == N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Local array size %" PetscInt_FMT " does not match 4d array dimensions %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT " by %" PetscInt_FMT, N, m, n, p, q);
3666:   PetscCall(VecGetArrayRead(x, &aa));

3668:   PetscCall(PetscMalloc(m * sizeof(PetscScalar ***) + m * n * sizeof(PetscScalar **) + m * n * p * sizeof(PetscScalar *), a));
3669:   b = (PetscScalar ***)((*a) + m);
3670:   c = (PetscScalar **)(b + m * n);
3671:   for (i = 0; i < m; i++) (*a)[i] = b + i * n - nstart;
3672:   for (i = 0; i < m; i++)
3673:     for (j = 0; j < n; j++) b[i * n + j] = c + i * n * p + j * p - pstart;
3674:   for (i = 0; i < m; i++)
3675:     for (j = 0; j < n; j++)
3676:       for (k = 0; k < p; k++) c[i * n * p + j * p + k] = (PetscScalar *)aa + i * n * p * q + j * p * q + k * q - qstart;
3677:   *a -= mstart;
3678:   PetscFunctionReturn(PETSC_SUCCESS);
3679: }

3681: /*@C
3682:   VecRestoreArray4dRead - Restores a vector after `VecGetArray4d()` has been called.

3684:   Logically Collective

3686:   Input Parameters:
3687: + x      - the vector
3688: . m      - first dimension of four dimensional array
3689: . n      - second dimension of the four dimensional array
3690: . p      - third dimension of the four dimensional array
3691: . q      - fourth dimension of the four dimensional array
3692: . mstart - first index you will use in first coordinate direction (often 0)
3693: . nstart - first index in the second coordinate direction (often 0)
3694: . pstart - first index in the third coordinate direction (often 0)
3695: . qstart - first index in the fourth coordinate direction (often 0)
3696: - a      - location of pointer to array obtained from `VecGetArray4dRead()`

3698:   Level: beginner

3700:   Notes:
3701:   For regular PETSc vectors this routine does not involve any copies. For
3702:   any special vectors that do not store local vector data in a contiguous
3703:   array, this routine will copy the data back into the underlying
3704:   vector data structure from the array obtained with `VecGetArray()`.

3706:   This routine actually zeros out the `a` pointer.

3708: .seealso: [](ch_vectors), `Vec`, `VecGetArray()`, `VecRestoreArray()`, `VecRestoreArrays()`, `VecPlaceArray()`,
3709:           `VecGetArray2d()`, `VecGetArray3d()`, `VecRestoreArray3d()`, `DMDAVecGetArray()`, `DMDAVecRestoreArray()`
3710:           `VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`
3711: @*/
3712: PetscErrorCode VecRestoreArray4dRead(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
3713: {
3714:   void *dummy;

3716:   PetscFunctionBegin;
3718:   PetscAssertPointer(a, 10);
3720:   dummy = (void *)(*a + mstart);
3721:   PetscCall(PetscFree(dummy));
3722:   PetscCall(VecRestoreArrayRead(x, NULL));
3723:   *a = NULL;
3724:   PetscFunctionReturn(PETSC_SUCCESS);
3725: }

3727: /*@
3728:   VecLockGet - Get the current lock status of a vector

3730:   Logically Collective

3732:   Input Parameter:
3733: . x - the vector

3735:   Output Parameter:
3736: . state - greater than zero indicates the vector is locked for read; less than zero indicates the vector is
3737:            locked for write; equal to zero means the vector is unlocked, that is, it is free to read or write.

3739:   Level: advanced

3741: .seealso: [](ch_vectors), `Vec`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecLockReadPush()`, `VecLockReadPop()`
3742: @*/
3743: PetscErrorCode VecLockGet(Vec x, PetscInt *state)
3744: {
3745:   PetscFunctionBegin;
3747:   PetscAssertPointer(state, 2);
3748:   *state = x->lock;
3749:   PetscFunctionReturn(PETSC_SUCCESS);
3750: }

3752: PetscErrorCode VecLockGetLocation(Vec x, const char *file[], const char *func[], int *line)
3753: {
3754:   PetscFunctionBegin;
3756:   PetscAssertPointer(file, 2);
3757:   PetscAssertPointer(func, 3);
3758:   PetscAssertPointer(line, 4);
3759: #if PetscDefined(USE_DEBUG) && !PetscDefined(HAVE_THREADSAFETY)
3760:   {
3761:     const int index = x->lockstack.currentsize - 1;

3763:     *file = index < 0 ? NULL : x->lockstack.file[index];
3764:     *func = index < 0 ? NULL : x->lockstack.function[index];
3765:     *line = index < 0 ? 0 : x->lockstack.line[index];
3766:   }
3767: #else
3768:   *file = NULL;
3769:   *func = NULL;
3770:   *line = 0;
3771: #endif
3772:   PetscFunctionReturn(PETSC_SUCCESS);
3773: }

3775: /*@
3776:   VecLockReadPush - Push a read-only lock on a vector to prevent it from being written to

3778:   Logically Collective

3780:   Input Parameter:
3781: . x - the vector

3783:   Level: intermediate

3785:   Notes:
3786:   If this is set then calls to `VecGetArray()` or `VecSetValues()` or any other routines that change the vectors values will generate an error.

3788:   The call can be nested, i.e., called multiple times on the same vector, but each `VecLockReadPush()` has to have one matching
3789:   `VecLockReadPop()`, which removes the latest read-only lock.

3791: .seealso: [](ch_vectors), `Vec`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecLockReadPop()`, `VecLockGet()`
3792: @*/
3793: PetscErrorCode VecLockReadPush(Vec x)
3794: {
3795:   PetscFunctionBegin;
3797:   PetscCheck(x->lock++ >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Vector is already locked for exclusive write access but you want to read it");
3798: #if PetscDefined(USE_DEBUG) && !PetscDefined(HAVE_THREADSAFETY)
3799:   {
3800:     const char *file, *func;
3801:     int         index, line;

3803:     if ((index = petscstack.currentsize - 2) < 0) {
3804:       // vec was locked "outside" of petsc, either in user-land or main. the error message will
3805:       // now show this function as the culprit, but it will include the stacktrace
3806:       file = "unknown user-file";
3807:       func = "unknown_user_function";
3808:       line = 0;
3809:     } else {
3810:       file = petscstack.file[index];
3811:       func = petscstack.function[index];
3812:       line = petscstack.line[index];
3813:     }
3814:     PetscStackPush_Private(x->lockstack, file, func, line, petscstack.petscroutine[index], PETSC_FALSE);
3815:   }
3816: #endif
3817:   PetscFunctionReturn(PETSC_SUCCESS);
3818: }

3820: /*@
3821:   VecLockReadPop - Pop a read-only lock from a vector

3823:   Logically Collective

3825:   Input Parameter:
3826: . x - the vector

3828:   Level: intermediate

3830: .seealso: [](ch_vectors), `Vec`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecLockReadPush()`, `VecLockGet()`
3831: @*/
3832: PetscErrorCode VecLockReadPop(Vec x)
3833: {
3834:   PetscFunctionBegin;
3836:   PetscCheck(--x->lock >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Vector has been unlocked from read-only access too many times");
3837: #if PetscDefined(USE_DEBUG) && !PetscDefined(HAVE_THREADSAFETY)
3838:   {
3839:     const char *previous = x->lockstack.function[x->lockstack.currentsize - 1];

3841:     PetscStackPop_Private(x->lockstack, previous);
3842:   }
3843: #endif
3844:   PetscFunctionReturn(PETSC_SUCCESS);
3845: }

3847: /*@
3848:   VecLockWriteSet - Lock or unlock a vector for exclusive read/write access

3850:   Logically Collective

3852:   Input Parameters:
3853: + x   - the vector
3854: - flg - `PETSC_TRUE` to lock the vector for exclusive read/write access; `PETSC_FALSE` to unlock it.

3856:   Level: intermediate

3858:   Notes:
3859:   The function is useful in split-phase computations, which usually have a begin phase and an end phase.
3860:   One can call `VecLockWriteSet`(x,`PETSC_TRUE`) in the begin phase to lock a vector for exclusive
3861:   access, and call `VecLockWriteSet`(x,`PETSC_FALSE`) in the end phase to unlock the vector from exclusive
3862:   access. In this way, one is ensured no other operations can access the vector in between. The code may like

3864: .vb
3865:        VecGetArray(x,&xdata); // begin phase
3866:        VecLockWriteSet(v,PETSC_TRUE);

3868:        Other operations, which can not access x anymore (they can access xdata, of course)

3870:        VecRestoreArray(x,&vdata); // end phase
3871:        VecLockWriteSet(v,PETSC_FALSE);
3872: .ve

3874:   The call can not be nested on the same vector, in other words, one can not call `VecLockWriteSet`(x,`PETSC_TRUE`)
3875:   again before calling `VecLockWriteSet`(v,`PETSC_FALSE`).

3877: .seealso: [](ch_vectors), `Vec`, `VecRestoreArray()`, `VecGetArrayRead()`, `VecLockReadPush()`, `VecLockReadPop()`, `VecLockGet()`
3878: @*/
3879: PetscErrorCode VecLockWriteSet(Vec x, PetscBool flg)
3880: {
3881:   PetscFunctionBegin;
3883:   if (flg) {
3884:     PetscCheck(x->lock <= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Vector is already locked for read-only access but you want to write it");
3885:     PetscCheck(x->lock >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Vector is already locked for exclusive write access but you want to write it");
3886:     x->lock = -1;
3887:   } else {
3888:     PetscCheck(x->lock == -1, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Vector is not locked for exclusive write access but you want to unlock it from that");
3889:     x->lock = 0;
3890:   }
3891:   PetscFunctionReturn(PETSC_SUCCESS);
3892: }