Actual source code: rvector.c

petsc-dev 2014-07-30
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  2: /*
  3:      Provides the interface functions for vector operations that have PetscScalar/PetscReal in the signature
  4:    These are the vector functions the user calls.
  5: */
  6: #include <petsc-private/vecimpl.h>       /*I  "petscvec.h"   I*/
  7: static PetscInt VecGetSubVectorSavedStateId = -1;

 10:   if ((x)->map->N != (y)->map->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Incompatible vector global lengths %d != %d", (x)->map->N, (y)->map->N); \
 11:   if ((x)->map->n != (y)->map->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Incompatible vector local lengths %d != %d", (x)->map->n, (y)->map->n);

 15: PETSC_EXTERN PetscErrorCode VecValidValues(Vec vec,PetscInt argnum,PetscBool begin)
 16: {
 17: #if defined(PETSC_USE_DEBUG)
 18:   PetscErrorCode    ierr;
 19:   PetscInt          n,i;
 20:   const PetscScalar *x;

 23: #if defined(PETSC_HAVE_CUSP)
 24:   if ((vec->petscnative || vec->ops->getarray) && vec->valid_GPU_array != PETSC_CUSP_GPU) {
 25: #else
 26:   if (vec->petscnative || vec->ops->getarray) {
 27: #endif
 28:     VecGetLocalSize(vec,&n);
 29:     VecGetArrayRead(vec,&x);
 30:     for (i=0; i<n; i++) {
 31:       if (begin) {
 32:         if (PetscIsInfOrNanScalar(x[i])) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FP,"Vec entry at local location %D is not-a-number or infinite at beginning of function: Parameter number %D",i,argnum);
 33:       } else {
 34:         if (PetscIsInfOrNanScalar(x[i])) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FP,"Vec entry at local location %D is not-a-number or infinite at end of function: Parameter number %D",i,argnum);
 35:       }
 36:     }
 37:     VecRestoreArrayRead(vec,&x);
 38:   }
 39:   return(0);
 40: #else
 41:   return 0;
 42: #endif
 43: }

 47: /*@
 48:    VecMaxPointwiseDivide - Computes the maximum of the componentwise division max = max_i abs(x_i/y_i).

 50:    Logically Collective on Vec

 52:    Input Parameters:
 53: .  x, y  - the vectors

 55:    Output Parameter:
 56: .  max - the result

 58:    Level: advanced

 60:    Notes: x and y may be the same vector
 61:           if a particular y_i is zero, it is treated as 1 in the above formula

 63: .seealso: VecPointwiseDivide(), VecPointwiseMult(), VecPointwiseMax(), VecPointwiseMin(), VecPointwiseMaxAbs()
 64: @*/
 65: PetscErrorCode  VecMaxPointwiseDivide(Vec x,Vec y,PetscReal *max)
 66: {


 78:   (*x->ops->maxpointwisedivide)(x,y,max);
 79:   return(0);
 80: }

 84: /*@
 85:    VecDot - Computes the vector dot product.

 87:    Collective on Vec

 89:    Input Parameters:
 90: .  x, y - the vectors

 92:    Output Parameter:
 93: .  val - the dot product

 95:    Performance Issues:
 96: $    per-processor memory bandwidth
 97: $    interprocessor latency
 98: $    work load inbalance that causes certain processes to arrive much earlier than others

100:    Notes for Users of Complex Numbers:
101:    For complex vectors, VecDot() computes
102: $     val = (x,y) = y^H x,
103:    where y^H denotes the conjugate transpose of y. Note that this corresponds to the usual "mathematicians" complex
104:    inner product where the SECOND argument gets the complex conjugate. Since the BLASdot() complex conjugates the first
105:    first argument we call the BLASdot() with the arguments reversed.

107:    Use VecTDot() for the indefinite form
108: $     val = (x,y) = y^T x,
109:    where y^T denotes the transpose of y.

111:    Level: intermediate

113:    Concepts: inner product
114:    Concepts: vector^inner product

116: .seealso: VecMDot(), VecTDot(), VecNorm(), VecDotBegin(), VecDotEnd(), VecDotRealPart()
117: @*/
118: PetscErrorCode  VecDot(Vec x,Vec y,PetscScalar *val)
119: {


131:   PetscLogEventBarrierBegin(VEC_DotBarrier,x,y,0,0,PetscObjectComm((PetscObject)x));
132:   (*x->ops->dot)(x,y,val);
133:   PetscLogEventBarrierEnd(VEC_DotBarrier,x,y,0,0,PetscObjectComm((PetscObject)x));
134:   return(0);
135: }

139: /*@
140:    VecDotRealPart - Computes the real part of the vector dot product.

142:    Collective on Vec

144:    Input Parameters:
145: .  x, y - the vectors

147:    Output Parameter:
148: .  val - the real part of the dot product;

150:    Performance Issues:
151: $    per-processor memory bandwidth
152: $    interprocessor latency
153: $    work load inbalance that causes certain processes to arrive much earlier than others

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

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

160:      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
161:      the space R^{2n} (that is a vector of 2n components with the real or imaginary part of the complex numbers for components)

163:    Developer Note: This is not currently optimized to compute only the real part of the dot product.

165:    Level: intermediate

167:    Concepts: inner product
168:    Concepts: vector^inner product

170: .seealso: VecMDot(), VecTDot(), VecNorm(), VecDotBegin(), VecDotEnd(), VecDot(), VecDotNorm2()
171: @*/
172: PetscErrorCode  VecDotRealPart(Vec x,Vec y,PetscReal *val)
173: {
175:   PetscScalar    fdot;

178:   VecDot(x,y,&fdot);
179:   *val = PetscRealPart(fdot);
180:   return(0);
181: }

185: /*@
186:    VecNorm  - Computes the vector norm.

188:    Collective on Vec

190:    Input Parameters:
191: +  x - the vector
192: -  type - one of NORM_1, NORM_2, NORM_INFINITY.  Also available
193:           NORM_1_AND_2, which computes both norms and stores them
194:           in a two element array.

196:    Output Parameter:
197: .  val - the norm

199:    Notes:
200: $     NORM_1 denotes sum_i |x_i|
201: $     NORM_2 denotes sqrt(sum_i (x_i)^2)
202: $     NORM_INFINITY denotes max_i |x_i|

204:    Level: intermediate

206:    Performance Issues:
207: $    per-processor memory bandwidth
208: $    interprocessor latency
209: $    work load inbalance that causes certain processes to arrive much earlier than others

211:    Compile Option:
212:    PETSC_HAVE_SLOW_BLAS_NORM2 will cause a C (loop unrolled) version of the norm to be used, rather
213:  than the BLAS. This should probably only be used when one is using the FORTRAN BLAS routines
214:  (as opposed to vendor provided) because the FORTRAN BLAS NRM2() routine is very slow.

216:    Concepts: norm
217:    Concepts: vector^norm

219: .seealso: VecDot(), VecTDot(), VecNorm(), VecDotBegin(), VecDotEnd(), VecNormAvailable(),
220:           VecNormBegin(), VecNormEnd()

222: @*/
223: PetscErrorCode  VecNorm(Vec x,NormType type,PetscReal *val)
224: {
225:   PetscBool      flg;

232:   if (((PetscObject)x)->precision != sizeof(PetscReal)) SETERRQ(PetscObjectComm((PetscObject)x),PETSC_ERR_SUP,"Wrong precision of input argument");

234:   /*
235:    * Cached data?
236:    */
237:   if (type!=NORM_1_AND_2) {
238:     PetscObjectComposedDataGetReal((PetscObject)x,NormIds[type],*val,flg);
239:     if (flg) return(0);
240:   }
241:   PetscLogEventBarrierBegin(VEC_NormBarrier,x,0,0,0,PetscObjectComm((PetscObject)x));
242:   (*x->ops->norm)(x,type,val);
243:   PetscLogEventBarrierEnd(VEC_NormBarrier,x,0,0,0,PetscObjectComm((PetscObject)x));

245:   if (type!=NORM_1_AND_2) {
246:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[type],*val);
247:   }
248:   return(0);
249: }

253: /*@
254:    VecNormAvailable  - Returns the vector norm if it is already known.

256:    Not Collective

258:    Input Parameters:
259: +  x - the vector
260: -  type - one of NORM_1, NORM_2, NORM_INFINITY.  Also available
261:           NORM_1_AND_2, which computes both norms and stores them
262:           in a two element array.

264:    Output Parameter:
265: +  available - PETSC_TRUE if the val returned is valid
266: -  val - the norm

268:    Notes:
269: $     NORM_1 denotes sum_i |x_i|
270: $     NORM_2 denotes sqrt(sum_i (x_i)^2)
271: $     NORM_INFINITY denotes max_i |x_i|

273:    Level: intermediate

275:    Performance Issues:
276: $    per-processor memory bandwidth
277: $    interprocessor latency
278: $    work load inbalance that causes certain processes to arrive much earlier than others

280:    Compile Option:
281:    PETSC_HAVE_SLOW_BLAS_NORM2 will cause a C (loop unrolled) version of the norm to be used, rather
282:  than the BLAS. This should probably only be used when one is using the FORTRAN BLAS routines
283:  (as opposed to vendor provided) because the FORTRAN BLAS NRM2() routine is very slow.

285:    Concepts: norm
286:    Concepts: vector^norm

288: .seealso: VecDot(), VecTDot(), VecNorm(), VecDotBegin(), VecDotEnd(), VecNorm()
289:           VecNormBegin(), VecNormEnd()

291: @*/
292: PetscErrorCode  VecNormAvailable(Vec x,NormType type,PetscBool  *available,PetscReal *val)
293: {


301:   *available = PETSC_FALSE;
302:   if (type!=NORM_1_AND_2) {
303:     PetscObjectComposedDataGetReal((PetscObject)x,NormIds[type],*val,*available);
304:   }
305:   return(0);
306: }

310: /*@
311:    VecNormalize - Normalizes a vector by 2-norm.

313:    Collective on Vec

315:    Input Parameters:
316: +  x - the vector

318:    Output Parameter:
319: .  x - the normalized vector
320: -  val - the vector norm before normalization

322:    Level: intermediate

324:    Concepts: vector^normalizing
325:    Concepts: normalizing^vector

327: @*/
328: PetscErrorCode  VecNormalize(Vec x,PetscReal *val)
329: {
331:   PetscReal      norm;

336:   PetscLogEventBegin(VEC_Normalize,x,0,0,0);
337:   VecNorm(x,NORM_2,&norm);
338:   if (norm == 0.0) {
339:     PetscInfo(x,"Vector of zero norm can not be normalized; Returning only the zero norm\n");
340:   } else if (norm != 1.0) {
341:     PetscScalar tmp = 1.0/norm;
342:     VecScale(x,tmp);
343:   }
344:   if (val) *val = norm;
345:   PetscLogEventEnd(VEC_Normalize,x,0,0,0);
346:   return(0);
347: }

351: /*@C
352:    VecMax - Determines the maximum vector component and its location.

354:    Collective on Vec

356:    Input Parameter:
357: .  x - the vector

359:    Output Parameters:
360: +  val - the maximum component
361: -  p - the location of val (pass NULL if you don't want this)

363:    Notes:
364:    Returns the value PETSC_MIN_REAL and p = -1 if the vector is of length 0.

366:    Returns the smallest index with the maximum value
367:    Level: intermediate

369:    Concepts: maximum^of vector
370:    Concepts: vector^maximum value

372: .seealso: VecNorm(), VecMin()
373: @*/
374: PetscErrorCode  VecMax(Vec x,PetscInt *p,PetscReal *val)
375: {

382:   PetscLogEventBegin(VEC_Max,x,0,0,0);
383:   (*x->ops->max)(x,p,val);
384:   PetscLogEventEnd(VEC_Max,x,0,0,0);
385:   return(0);
386: }

390: /*@
391:    VecMin - Determines the minimum vector component and its location.

393:    Collective on Vec

395:    Input Parameters:
396: .  x - the vector

398:    Output Parameter:
399: +  val - the minimum component
400: -  p - the location of val (pass NULL if you don't want this location)

402:    Level: intermediate

404:    Notes:
405:    Returns the value PETSC_MAX_REAL and p = -1 if the vector is of length 0.

407:    This returns the smallest index with the minumum value

409:    Concepts: minimum^of vector
410:    Concepts: vector^minimum entry

412: .seealso: VecMax()
413: @*/
414: PetscErrorCode  VecMin(Vec x,PetscInt *p,PetscReal *val)
415: {

422:   PetscLogEventBegin(VEC_Min,x,0,0,0);
423:   (*x->ops->min)(x,p,val);
424:   PetscLogEventEnd(VEC_Min,x,0,0,0);
425:   return(0);
426: }

430: /*@
431:    VecTDot - Computes an indefinite vector dot product. That is, this
432:    routine does NOT use the complex conjugate.

434:    Collective on Vec

436:    Input Parameters:
437: .  x, y - the vectors

439:    Output Parameter:
440: .  val - the dot product

442:    Notes for Users of Complex Numbers:
443:    For complex vectors, VecTDot() computes the indefinite form
444: $     val = (x,y) = y^T x,
445:    where y^T denotes the transpose of y.

447:    Use VecDot() for the inner product
448: $     val = (x,y) = y^H x,
449:    where y^H denotes the conjugate transpose of y.

451:    Level: intermediate

453:    Concepts: inner product^non-Hermitian
454:    Concepts: vector^inner product
455:    Concepts: non-Hermitian inner product

457: .seealso: VecDot(), VecMTDot()
458: @*/
459: PetscErrorCode  VecTDot(Vec x,Vec y,PetscScalar *val)
460: {


472:   PetscLogEventBegin(VEC_TDot,x,y,0,0);
473:   (*x->ops->tdot)(x,y,val);
474:   PetscLogEventEnd(VEC_TDot,x,y,0,0);
475:   return(0);
476: }

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

483:    Not collective on Vec

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

489:    Output Parameter:
490: .  x - the scaled vector

492:    Note:
493:    For a vector with n components, VecScale() computes
494: $      x[i] = alpha * x[i], for i=1,...,n.

496:    Level: intermediate

498:    Concepts: vector^scaling
499:    Concepts: scaling^vector

501: @*/
502: PetscErrorCode  VecScale(Vec x, PetscScalar alpha)
503: {
504:   PetscReal      norms[4] = {0.0,0.0,0.0, 0.0};
505:   PetscBool      flgs[4];
507:   PetscInt       i;

512:   if (x->stash.insertmode != NOT_SET_VALUES) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled vector");
513:   PetscLogEventBegin(VEC_Scale,x,0,0,0);
514:   if (alpha != (PetscScalar)1.0) {
515:     /* get current stashed norms */
516:     for (i=0; i<4; i++) {
517:       PetscObjectComposedDataGetReal((PetscObject)x,NormIds[i],norms[i],flgs[i]);
518:     }
519:     (*x->ops->scale)(x,alpha);
520:     PetscObjectStateIncrease((PetscObject)x);
521:     /* put the scaled stashed norms back into the Vec */
522:     for (i=0; i<4; i++) {
523:       if (flgs[i]) {
524:         PetscObjectComposedDataSetReal((PetscObject)x,NormIds[i],PetscAbsScalar(alpha)*norms[i]);
525:       }
526:     }
527:   }
528:   PetscLogEventEnd(VEC_Scale,x,0,0,0);
529:   return(0);
530: }

534: /*@
535:    VecSet - Sets all components of a vector to a single scalar value.

537:    Logically Collective on Vec

539:    Input Parameters:
540: +  x  - the vector
541: -  alpha - the scalar

543:    Output Parameter:
544: .  x  - the vector

546:    Note:
547:    For a vector of dimension n, VecSet() computes
548: $     x[i] = alpha, for i=1,...,n,
549:    so that all vector entries then equal the identical
550:    scalar value, alpha.  Use the more general routine
551:    VecSetValues() to set different vector entries.

553:    You CANNOT call this after you have called VecSetValues() but before you call
554:    VecAssemblyBegin/End().

556:    Level: beginner

558: .seealso VecSetValues(), VecSetValuesBlocked(), VecSetRandom()

560:    Concepts: vector^setting to constant

562: @*/
563: PetscErrorCode  VecSet(Vec x,PetscScalar alpha)
564: {
565:   PetscReal      val;

571:   if (x->stash.insertmode != NOT_SET_VALUES) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"You cannot call this after you have called VecSetValues() but\n before you have called VecAssemblyBegin/End()");

574:   PetscLogEventBegin(VEC_Set,x,0,0,0);
575:   (*x->ops->set)(x,alpha);
576:   PetscLogEventEnd(VEC_Set,x,0,0,0);
577:   PetscObjectStateIncrease((PetscObject)x);

579:   /*  norms can be simply set (if |alpha|*N not too large) */
580:   val  = PetscAbsScalar(alpha);
581:   if (x->map->N == 0) {
582:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_1],0.0l);
583:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_INFINITY],0.0);
584:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_2],0.0);
585:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_FROBENIUS],0.0);
586:   } else if (val > PETSC_MAX_REAL/x->map->N) {
587:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_INFINITY],val);
588:   } else {
589:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_1],x->map->N * val);
590:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_INFINITY],val);
591:     val  = PetscSqrtReal((PetscReal)x->map->N) * val;
592:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_2],val);
593:     PetscObjectComposedDataSetReal((PetscObject)x,NormIds[NORM_FROBENIUS],val);
594:   }
595:   return(0);
596: }


601: /*@
602:    VecAXPY - Computes y = alpha x + y.

604:    Logically Collective on Vec

606:    Input Parameters:
607: +  alpha - the scalar
608: -  x, y  - the vectors

610:    Output Parameter:
611: .  y - output vector

613:    Level: intermediate

615:    Notes: x and y MUST be different vectors

617:    Concepts: vector^BLAS
618:    Concepts: BLAS

620: .seealso: VecAYPX(), VecMAXPY(), VecWAXPY()
621: @*/
622: PetscErrorCode  VecAXPY(Vec y,PetscScalar alpha,Vec x)
623: {

633:   if (x == y) SETERRQ(PetscObjectComm((PetscObject)x),PETSC_ERR_ARG_IDN,"x and y cannot be the same vector");

636:   PetscLogEventBegin(VEC_AXPY,x,y,0,0);
637:   (*y->ops->axpy)(y,alpha,x);
638:   PetscLogEventEnd(VEC_AXPY,x,y,0,0);
639:   PetscObjectStateIncrease((PetscObject)y);
640:   return(0);
641: }

645: /*@
646:    VecAXPBY - Computes y = alpha x + beta y.

648:    Logically Collective on Vec

650:    Input Parameters:
651: +  alpha,beta - the scalars
652: -  x, y  - the vectors

654:    Output Parameter:
655: .  y - output vector

657:    Level: intermediate

659:    Notes: x and y MUST be different vectors

661:    Concepts: BLAS
662:    Concepts: vector^BLAS

664: .seealso: VecAYPX(), VecMAXPY(), VecWAXPY(), VecAXPY()
665: @*/
666: PetscErrorCode  VecAXPBY(Vec y,PetscScalar alpha,PetscScalar beta,Vec x)
667: {

677:   if (x == y) SETERRQ(PetscObjectComm((PetscObject)x),PETSC_ERR_ARG_IDN,"x and y cannot be the same vector");

681:   PetscLogEventBegin(VEC_AXPY,x,y,0,0);
682:   (*y->ops->axpby)(y,alpha,beta,x);
683:   PetscLogEventEnd(VEC_AXPY,x,y,0,0);
684:   PetscObjectStateIncrease((PetscObject)y);
685:   return(0);
686: }

690: /*@
691:    VecAXPBYPCZ - Computes z = alpha x + beta y + gamma z

693:    Logically Collective on Vec

695:    Input Parameters:
696: +  alpha,beta, gamma - the scalars
697: -  x, y, z  - the vectors

699:    Output Parameter:
700: .  z - output vector

702:    Level: intermediate

704:    Notes: x, y and z must be different vectors

706:    Developer Note:   alpha = 1 or gamma = 1 or gamma = 0.0 are handled as special cases

708:    Concepts: BLAS
709:    Concepts: vector^BLAS

711: .seealso: VecAYPX(), VecMAXPY(), VecWAXPY(), VecAXPY()
712: @*/
713: PetscErrorCode  VecAXPBYPCZ(Vec z,PetscScalar alpha,PetscScalar beta,PetscScalar gamma,Vec x,Vec y)
714: {

728:   if (x == y || x == z) SETERRQ(PetscObjectComm((PetscObject)x),PETSC_ERR_ARG_IDN,"x, y, and z must be different vectors");
729:   if (y == z) SETERRQ(PetscObjectComm((PetscObject)y),PETSC_ERR_ARG_IDN,"x, y, and z must be different vectors");

734:   PetscLogEventBegin(VEC_AXPBYPCZ,x,y,z,0);
735:   (*y->ops->axpbypcz)(z,alpha,beta,gamma,x,y);
736:   PetscLogEventEnd(VEC_AXPBYPCZ,x,y,z,0);
737:   PetscObjectStateIncrease((PetscObject)z);
738:   return(0);
739: }

743: /*@
744:    VecAYPX - Computes y = x + alpha y.

746:    Logically Collective on Vec

748:    Input Parameters:
749: +  alpha - the scalar
750: -  x, y  - the vectors

752:    Output Parameter:
753: .  y - output vector

755:    Level: intermediate

757:    Notes: x and y MUST be different vectors

759:    Concepts: vector^BLAS
760:    Concepts: BLAS

762: .seealso: VecAXPY(), VecWAXPY()
763: @*/
764: PetscErrorCode  VecAYPX(Vec y,PetscScalar alpha,Vec x)
765: {

773:   if (x == y) SETERRQ(PetscObjectComm((PetscObject)x),PETSC_ERR_ARG_IDN,"x and y must be different vectors");

776:   PetscLogEventBegin(VEC_AYPX,x,y,0,0);
777:    (*y->ops->aypx)(y,alpha,x);
778:   PetscLogEventEnd(VEC_AYPX,x,y,0,0);
779:   PetscObjectStateIncrease((PetscObject)y);
780:   return(0);
781: }


786: /*@
787:    VecWAXPY - Computes w = alpha x + y.

789:    Logically Collective on Vec

791:    Input Parameters:
792: +  alpha - the scalar
793: -  x, y  - the vectors

795:    Output Parameter:
796: .  w - the result

798:    Level: intermediate

800:    Notes: w cannot be either x or y, but x and y can be the same

802:    Concepts: vector^BLAS
803:    Concepts: BLAS

805: .seealso: VecAXPY(), VecAYPX(), VecAXPBY()
806: @*/
807: PetscErrorCode  VecWAXPY(Vec w,PetscScalar alpha,Vec x,Vec y)
808: {

822:   if (w == y) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Result vector w cannot be same as input vector y, suggest VecAXPY()");
823:   if (w == x) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Result vector w cannot be same as input vector x, suggest VecAYPX()");

826:   PetscLogEventBegin(VEC_WAXPY,x,y,w,0);
827:    (*w->ops->waxpy)(w,alpha,x,y);
828:   PetscLogEventEnd(VEC_WAXPY,x,y,w,0);
829:   PetscObjectStateIncrease((PetscObject)w);
830:   return(0);
831: }


836: /*@
837:    VecSetValues - Inserts or adds values into certain locations of a vector.

839:    Not Collective

841:    Input Parameters:
842: +  x - vector to insert in
843: .  ni - number of elements to add
844: .  ix - indices where to add
845: .  y - array of values
846: -  iora - either INSERT_VALUES or ADD_VALUES, where
847:    ADD_VALUES adds values to any existing entries, and
848:    INSERT_VALUES replaces existing entries with new values

850:    Notes:
851:    VecSetValues() sets x[ix[i]] = y[i], for i=0,...,ni-1.

853:    Calls to VecSetValues() with the INSERT_VALUES and ADD_VALUES
854:    options cannot be mixed without intervening calls to the assembly
855:    routines.

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

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

862:    If you call VecSetOption(x, VEC_IGNORE_NEGATIVE_INDICES,PETSC_TRUE),
863:    negative indices may be passed in ix. These rows are
864:    simply ignored. This allows easily inserting element load matrices
865:    with homogeneous Dirchlet boundary conditions that you don't want represented
866:    in the vector.

868:    Level: beginner

870:    Concepts: vector^setting values

872: .seealso:  VecAssemblyBegin(), VecAssemblyEnd(), VecSetValuesLocal(),
873:            VecSetValue(), VecSetValuesBlocked(), InsertMode, INSERT_VALUES, ADD_VALUES, VecGetValues()
874: @*/
875: PetscErrorCode  VecSetValues(Vec x,PetscInt ni,const PetscInt ix[],const PetscScalar y[],InsertMode iora)
876: {

884:   PetscLogEventBegin(VEC_SetValues,x,0,0,0);
885:   (*x->ops->setvalues)(x,ni,ix,y,iora);
886:   PetscLogEventEnd(VEC_SetValues,x,0,0,0);
887:   PetscObjectStateIncrease((PetscObject)x);
888:   return(0);
889: }

893: /*@
894:    VecGetValues - Gets values from certain locations of a vector. Currently
895:           can only get values on the same processor

897:     Not Collective

899:    Input Parameters:
900: +  x - vector to get values from
901: .  ni - number of elements to get
902: -  ix - indices where to get them from (in global 1d numbering)

904:    Output Parameter:
905: .   y - array of values

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

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

912:    VecAssemblyBegin() and VecAssemblyEnd()  MUST be called before calling this

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

916:    If you call VecSetOption(x, VEC_IGNORE_NEGATIVE_INDICES,PETSC_TRUE),
917:    negative indices may be passed in ix. These rows are
918:    simply ignored.

920:    Level: beginner

922:    Concepts: vector^getting values

924: .seealso:  VecAssemblyBegin(), VecAssemblyEnd(), VecGetValuesLocal(),
925:            VecGetValuesBlocked(), InsertMode, INSERT_VALUES, ADD_VALUES, VecSetValues()
926: @*/
927: PetscErrorCode  VecGetValues(Vec x,PetscInt ni,const PetscInt ix[],PetscScalar y[])
928: {

936:   (*x->ops->getvalues)(x,ni,ix,y);
937:   return(0);
938: }

942: /*@
943:    VecSetValuesBlocked - Inserts or adds blocks of values into certain locations of a vector.

945:    Not Collective

947:    Input Parameters:
948: +  x - vector to insert in
949: .  ni - number of blocks to add
950: .  ix - indices where to add in block count, rather than element count
951: .  y - array of values
952: -  iora - either INSERT_VALUES or ADD_VALUES, where
953:    ADD_VALUES adds values to any existing entries, and
954:    INSERT_VALUES replaces existing entries with new values

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

960:    Calls to VecSetValuesBlocked() with the INSERT_VALUES and ADD_VALUES
961:    options cannot be mixed without intervening calls to the assembly
962:    routines.

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

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

969:    Negative indices may be passed in ix, these rows are
970:    simply ignored. This allows easily inserting element load matrices
971:    with homogeneous Dirchlet boundary conditions that you don't want represented
972:    in the vector.

974:    Level: intermediate

976:    Concepts: vector^setting values blocked

978: .seealso:  VecAssemblyBegin(), VecAssemblyEnd(), VecSetValuesBlockedLocal(),
979:            VecSetValues()
980: @*/
981: PetscErrorCode  VecSetValuesBlocked(Vec x,PetscInt ni,const PetscInt ix[],const PetscScalar y[],InsertMode iora)
982: {

990:   PetscLogEventBegin(VEC_SetValues,x,0,0,0);
991:   (*x->ops->setvaluesblocked)(x,ni,ix,y,iora);
992:   PetscLogEventEnd(VEC_SetValues,x,0,0,0);
993:   PetscObjectStateIncrease((PetscObject)x);
994:   return(0);
995: }


1000: /*@
1001:    VecSetValuesLocal - Inserts or adds values into certain locations of a vector,
1002:    using a local ordering of the nodes.

1004:    Not Collective

1006:    Input Parameters:
1007: +  x - vector to insert in
1008: .  ni - number of elements to add
1009: .  ix - indices where to add
1010: .  y - array of values
1011: -  iora - either INSERT_VALUES or ADD_VALUES, where
1012:    ADD_VALUES adds values to any existing entries, and
1013:    INSERT_VALUES replaces existing entries with new values

1015:    Level: intermediate

1017:    Notes:
1018:    VecSetValuesLocal() sets x[ix[i]] = y[i], for i=0,...,ni-1.

1020:    Calls to VecSetValues() with the INSERT_VALUES and ADD_VALUES
1021:    options cannot be mixed without intervening calls to the assembly
1022:    routines.

1024:    These values may be cached, so VecAssemblyBegin() and VecAssemblyEnd()
1025:    MUST be called after all calls to VecSetValuesLocal() have been completed.

1027:    VecSetValuesLocal() uses 0-based indices in Fortran as well as in C.

1029:    Concepts: vector^setting values with local numbering

1031: .seealso:  VecAssemblyBegin(), VecAssemblyEnd(), VecSetValues(), VecSetLocalToGlobalMapping(),
1032:            VecSetValuesBlockedLocal()
1033: @*/
1034: PetscErrorCode  VecSetValuesLocal(Vec x,PetscInt ni,const PetscInt ix[],const PetscScalar y[],InsertMode iora)
1035: {
1037:   PetscInt       lixp[128],*lix = lixp;


1045:   PetscLogEventBegin(VEC_SetValues,x,0,0,0);
1046:   if (!x->ops->setvalueslocal) {
1047:     if (!x->map->mapping) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Local to global never set with VecSetLocalToGlobalMapping()");
1048:     if (ni > 128) {
1049:       PetscMalloc1(ni,&lix);
1050:     }
1051:     ISLocalToGlobalMappingApply(x->map->mapping,ni,(PetscInt*)ix,lix);
1052:     (*x->ops->setvalues)(x,ni,lix,y,iora);
1053:     if (ni > 128) {
1054:       PetscFree(lix);
1055:     }
1056:   } else {
1057:     (*x->ops->setvalueslocal)(x,ni,ix,y,iora);
1058:   }
1059:   PetscLogEventEnd(VEC_SetValues,x,0,0,0);
1060:   PetscObjectStateIncrease((PetscObject)x);
1061:   return(0);
1062: }

1066: /*@
1067:    VecSetValuesBlockedLocal - Inserts or adds values into certain locations of a vector,
1068:    using a local ordering of the nodes.

1070:    Not Collective

1072:    Input Parameters:
1073: +  x - vector to insert in
1074: .  ni - number of blocks to add
1075: .  ix - indices where to add in block count, not element count
1076: .  y - array of values
1077: -  iora - either INSERT_VALUES or ADD_VALUES, where
1078:    ADD_VALUES adds values to any existing entries, and
1079:    INSERT_VALUES replaces existing entries with new values

1081:    Level: intermediate

1083:    Notes:
1084:    VecSetValuesBlockedLocal() sets x[bs*ix[i]+j] = y[bs*i+j],
1085:    for j=0,..bs-1, for i=0,...,ni-1, where bs has been set with VecSetBlockSize().

1087:    Calls to VecSetValuesBlockedLocal() with the INSERT_VALUES and ADD_VALUES
1088:    options cannot be mixed without intervening calls to the assembly
1089:    routines.

1091:    These values may be cached, so VecAssemblyBegin() and VecAssemblyEnd()
1092:    MUST be called after all calls to VecSetValuesBlockedLocal() have been completed.

1094:    VecSetValuesBlockedLocal() uses 0-based indices in Fortran as well as in C.


1097:    Concepts: vector^setting values blocked with local numbering

1099: .seealso:  VecAssemblyBegin(), VecAssemblyEnd(), VecSetValues(), VecSetValuesBlocked(),
1100:            VecSetLocalToGlobalMapping()
1101: @*/
1102: PetscErrorCode  VecSetValuesBlockedLocal(Vec x,PetscInt ni,const PetscInt ix[],const PetscScalar y[],InsertMode iora)
1103: {
1105:   PetscInt       lixp[128],*lix = lixp;

1112:   if (ni > 128) {
1113:     PetscMalloc1(ni,&lix);
1114:   }

1116:   PetscLogEventBegin(VEC_SetValues,x,0,0,0);
1117:   ISLocalToGlobalMappingApplyBlock(x->map->mapping,ni,(PetscInt*)ix,lix);
1118:   (*x->ops->setvaluesblocked)(x,ni,lix,y,iora);
1119:   PetscLogEventEnd(VEC_SetValues,x,0,0,0);
1120:   if (ni > 128) {
1121:     PetscFree(lix);
1122:   }
1123:   PetscObjectStateIncrease((PetscObject)x);
1124:   return(0);
1125: }

1129: /*@
1130:    VecMTDot - Computes indefinite vector multiple dot products.
1131:    That is, it does NOT use the complex conjugate.

1133:    Collective on Vec

1135:    Input Parameters:
1136: +  x - one vector
1137: .  nv - number of vectors
1138: -  y - array of vectors.  Note that vectors are pointers

1140:    Output Parameter:
1141: .  val - array of the dot products

1143:    Notes for Users of Complex Numbers:
1144:    For complex vectors, VecMTDot() computes the indefinite form
1145: $      val = (x,y) = y^T x,
1146:    where y^T denotes the transpose of y.

1148:    Use VecMDot() for the inner product
1149: $      val = (x,y) = y^H x,
1150:    where y^H denotes the conjugate transpose of y.

1152:    Level: intermediate

1154:    Concepts: inner product^multiple
1155:    Concepts: vector^multiple inner products

1157: .seealso: VecMDot(), VecTDot()
1158: @*/
1159: PetscErrorCode  VecMTDot(Vec x,PetscInt nv,const Vec y[],PetscScalar val[])
1160: {


1173:   PetscLogEventBegin(VEC_MTDot,x,*y,0,0);
1174:   (*x->ops->mtdot)(x,nv,y,val);
1175:   PetscLogEventEnd(VEC_MTDot,x,*y,0,0);
1176:   return(0);
1177: }

1181: /*@
1182:    VecMDot - Computes vector multiple dot products.

1184:    Collective on Vec

1186:    Input Parameters:
1187: +  x - one vector
1188: .  nv - number of vectors
1189: -  y - array of vectors.

1191:    Output Parameter:
1192: .  val - array of the dot products (does not allocate the array)

1194:    Notes for Users of Complex Numbers:
1195:    For complex vectors, VecMDot() computes
1196: $     val = (x,y) = y^H x,
1197:    where y^H denotes the conjugate transpose of y.

1199:    Use VecMTDot() for the indefinite form
1200: $     val = (x,y) = y^T x,
1201:    where y^T denotes the transpose of y.

1203:    Level: intermediate

1205:    Concepts: inner product^multiple
1206:    Concepts: vector^multiple inner products

1208: .seealso: VecMTDot(), VecDot()
1209: @*/
1210: PetscErrorCode  VecMDot(Vec x,PetscInt nv,const Vec y[],PetscScalar val[])
1211: {

1216:   if (!nv) return(0);
1217:   if (nv < 0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Number of vectors (given %D) cannot be negative",nv);

1226:   PetscLogEventBarrierBegin(VEC_MDotBarrier,x,*y,0,0,PetscObjectComm((PetscObject)x));
1227:   (*x->ops->mdot)(x,nv,y,val);
1228:   PetscLogEventBarrierEnd(VEC_MDotBarrier,x,*y,0,0,PetscObjectComm((PetscObject)x));
1229:   return(0);
1230: }

1234: /*@
1235:    VecMAXPY - Computes y = y + sum alpha[j] x[j]

1237:    Logically Collective on Vec

1239:    Input Parameters:
1240: +  nv - number of scalars and x-vectors
1241: .  alpha - array of scalars
1242: .  y - one vector
1243: -  x - array of vectors

1245:    Level: intermediate

1247:    Notes: y cannot be any of the x vectors

1249:    Concepts: BLAS

1251: .seealso: VecAXPY(), VecWAXPY(), VecAYPX()
1252: @*/
1253: PetscErrorCode  VecMAXPY(Vec y,PetscInt nv,const PetscScalar alpha[],Vec x[])
1254: {
1256:   PetscInt       i;

1260:   if (!nv) return(0);
1261:   if (nv < 0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Number of vectors (given %D) cannot be negative",nv);

1271:   PetscLogEventBegin(VEC_MAXPY,*x,y,0,0);
1272:   (*y->ops->maxpy)(y,nv,alpha,x);
1273:   PetscLogEventEnd(VEC_MAXPY,*x,y,0,0);
1274:   PetscObjectStateIncrease((PetscObject)y);
1275:   return(0);
1276: }

1280: /*@
1281:    VecGetSubVector - Gets a vector representing part of another vector

1283:    Collective on IS (and Vec if nonlocal entries are needed)

1285:    Input Arguments:
1286: + X - vector from which to extract a subvector
1287: - is - index set representing portion of X to extract

1289:    Output Arguments:
1290: . Y - subvector corresponding to is

1292:    Level: advanced

1294:    Notes:
1295:    The subvector Y should be returned with VecRestoreSubVector().

1297:    This function may return a subvector without making a copy, therefore it is not safe to use the original vector while
1298:    modifying the subvector.  Other non-overlapping subvectors can still be obtained from X using this function.

1300: .seealso: MatGetSubMatrix()
1301: @*/
1302: PetscErrorCode  VecGetSubVector(Vec X,IS is,Vec *Y)
1303: {
1304:   PetscErrorCode   ierr;
1305:   Vec              Z;
1306:   PetscObjectState state;

1312:   if (X->ops->getsubvector) {
1313:     (*X->ops->getsubvector)(X,is,&Z);
1314:   } else {                      /* Default implementation currently does no caching */
1315:     PetscInt  gstart,gend,start;
1316:     PetscBool contiguous,gcontiguous;
1317:     VecGetOwnershipRange(X,&gstart,&gend);
1318:     ISContiguousLocal(is,gstart,gend,&start,&contiguous);
1319:     MPI_Allreduce(&contiguous,&gcontiguous,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)is));
1320:     if (gcontiguous) {          /* We can do a no-copy implementation */
1321:       PetscInt    n,N,bs;
1322:       PetscScalar *x;
1323:       PetscMPIInt size;
1324:       ISGetLocalSize(is,&n);
1325:       VecGetArray(X,&x);
1326:       VecGetBlockSize(X,&bs);
1327:       if (n%bs) bs = 1;
1328:       MPI_Comm_size(PetscObjectComm((PetscObject)X),&size);
1329:       if (size == 1) {
1330:         VecCreateSeqWithArray(PetscObjectComm((PetscObject)X),bs,n,x+start,&Z);
1331:       } else {
1332:         ISGetSize(is,&N);
1333:         VecCreateMPIWithArray(PetscObjectComm((PetscObject)X),bs,n,N,x+start,&Z);
1334:       }
1335:       VecRestoreArray(X,&x);
1336:     } else {                    /* Have to create a scatter and do a copy */
1337:       VecScatter scatter;
1338:       PetscInt   n,N;
1339:       ISGetLocalSize(is,&n);
1340:       ISGetSize(is,&N);
1341:       VecCreate(PetscObjectComm((PetscObject)is),&Z);
1342:       VecSetSizes(Z,n,N);
1343:       VecSetType(Z,((PetscObject)X)->type_name);
1344:       VecScatterCreate(X,is,Z,NULL,&scatter);
1345:       VecScatterBegin(scatter,X,Z,INSERT_VALUES,SCATTER_FORWARD);
1346:       VecScatterEnd(scatter,X,Z,INSERT_VALUES,SCATTER_FORWARD);
1347:       VecScatterDestroy(&scatter);
1348:     }
1349:   }
1350:   /* Record the state when the subvector was gotten so we know whether its values need to be put back */
1351:   if (VecGetSubVectorSavedStateId < 0) {PetscObjectComposedDataRegister(&VecGetSubVectorSavedStateId);}
1352:   PetscObjectStateGet((PetscObject)Z,&state);
1353:   PetscObjectComposedDataSetInt((PetscObject)Z,VecGetSubVectorSavedStateId,state);
1354:   *Y   = Z;
1355:   return(0);
1356: }

1360: /*@
1361:    VecRestoreSubVector - Restores a subvector extracted using VecGetSubVector()

1363:    Collective on IS (and Vec if nonlocal entries need to be written)

1365:    Input Arguments:
1366: + X - vector from which subvector was obtained
1367: . is - index set representing the subset of X
1368: - Y - subvector being restored

1370:    Level: advanced

1372: .seealso: VecGetSubVector()
1373: @*/
1374: PetscErrorCode  VecRestoreSubVector(Vec X,IS is,Vec *Y)
1375: {

1383:   if (X->ops->restoresubvector) {
1384:     (*X->ops->restoresubvector)(X,is,Y);
1385:   } else {
1386:     PetscObjectState savedstate=0,newstate;
1387:     PetscBool valid;
1388:     PetscObjectComposedDataGetInt((PetscObject)*Y,VecGetSubVectorSavedStateId,savedstate,valid);
1389:     PetscObjectStateGet((PetscObject)*Y,&newstate);
1390:     if (valid && savedstate < newstate) {
1391:       /* We might need to copy entries back, first check whether we have no-copy view */
1392:       PetscInt  gstart,gend,start;
1393:       PetscBool contiguous,gcontiguous;
1394:       VecGetOwnershipRange(X,&gstart,&gend);
1395:       ISContiguousLocal(is,gstart,gend,&start,&contiguous);
1396:       MPI_Allreduce(&contiguous,&gcontiguous,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)is));
1397:       if (!gcontiguous) SETERRQ(PetscObjectComm((PetscObject)is),PETSC_ERR_SUP,"Unhandled case, values have been changed and need to be copied back into X");
1398:     }
1399:     VecDestroy(Y);
1400:   }
1401:   return(0);
1402: }

1406: /*@C
1407:    VecGetArray - Returns a pointer to a contiguous array that contains this
1408:    processor's portion of the vector data. For the standard PETSc
1409:    vectors, VecGetArray() returns a pointer to the local data array and
1410:    does not use any copies. If the underlying vector data is not stored
1411:    in a contiquous array this routine will copy the data to a contiquous
1412:    array and return a pointer to that. You MUST call VecRestoreArray()
1413:    when you no longer need access to the array.

1415:    Logically Collective on Vec

1417:    Input Parameter:
1418: .  x - the vector

1420:    Output Parameter:
1421: .  a - location to put pointer to the array

1423:    Fortran Note:
1424:    This routine is used differently from Fortran 77
1425: $    Vec         x
1426: $    PetscScalar x_array(1)
1427: $    PetscOffset i_x
1428: $    PetscErrorCode ierr
1429: $       call VecGetArray(x,x_array,i_x,ierr)
1430: $
1431: $   Access first local entry in vector with
1432: $      value = x_array(i_x + 1)
1433: $
1434: $      ...... other code
1435: $       call VecRestoreArray(x,x_array,i_x,ierr)
1436:    For Fortran 90 see VecGetArrayF90()

1438:    See the Fortran chapter of the users manual and
1439:    petsc/src/snes/examples/tutorials/ex5f.F for details.

1441:    Level: beginner

1443:    Concepts: vector^accessing local values

1445: .seealso: VecRestoreArray(), VecGetArrayRead(), VecGetArrays(), VecGetArrayF90(), VecPlaceArray(), VecGetArray2d()
1446: @*/
1447: PetscErrorCode VecGetArray(Vec x,PetscScalar **a)
1448: {

1453:   if (x->petscnative) {
1454: #if defined(PETSC_HAVE_CUSP)
1455:     if (x->valid_GPU_array == PETSC_CUSP_GPU) {
1456:       VecCUSPCopyFromGPU(x);
1457:     }
1458: #endif
1459: #if defined(PETSC_HAVE_VIENNACL)
1460:     if (x->valid_GPU_array == PETSC_VIENNACL_GPU) {
1461:       VecViennaCLCopyFromGPU(x);
1462:     }
1463: #endif
1464:     *a = *((PetscScalar **)x->data);
1465:   } else {
1466:     (*x->ops->getarray)(x,a);
1467:   }
1468:   return(0);
1469: }

1473: /*@C
1474:    VecGetArrayRead - Get read-only pointer to contiguous array containing this processor's portion of the vector data.

1476:    Not Collective

1478:    Input Parameters:
1479: .  x - the vector

1481:    Output Parameter:
1482: .  a - the array

1484:    Level: beginner

1486:    Notes:
1487:    The array must be returned using a matching call to VecRestoreArrayRead().

1489:    Unlike VecGetArray(), this routine is not collective and preserves cached information like vector norms.

1491:    Standard PETSc vectors use contiguous storage so that this routine does not perform a copy.  Other vector
1492:    implementations may require a copy, but must such implementations should cache the contiguous representation so that
1493:    only one copy is performed when this routine is called multiple times in sequence.

1495: .seealso: VecGetArray(), VecRestoreArray()
1496: @*/
1497: PetscErrorCode VecGetArrayRead(Vec x,const PetscScalar **a)
1498: {

1503:   if (x->petscnative) {
1504: #if defined(PETSC_HAVE_CUSP)
1505:     if (x->valid_GPU_array == PETSC_CUSP_GPU) {
1506:       VecCUSPCopyFromGPU(x);
1507:     }
1508: #endif
1509: #if defined(PETSC_HAVE_VIENNACL)
1510:     if (x->valid_GPU_array == PETSC_VIENNACL_GPU) {
1511:       VecViennaCLCopyFromGPU(x);
1512:     }
1513: #endif
1514:     *a = *((PetscScalar **)x->data);
1515:   } else if (x->ops->getarrayread) {
1516:     (*x->ops->getarrayread)(x,a);
1517:   } else {
1518:     (*x->ops->getarray)(x,(PetscScalar**)a);
1519:   }
1520:   return(0);
1521: }

1525: /*@C
1526:    VecGetArrays - Returns a pointer to the arrays in a set of vectors
1527:    that were created by a call to VecDuplicateVecs().  You MUST call
1528:    VecRestoreArrays() when you no longer need access to the array.

1530:    Logically Collective on Vec

1532:    Input Parameter:
1533: +  x - the vectors
1534: -  n - the number of vectors

1536:    Output Parameter:
1537: .  a - location to put pointer to the array

1539:    Fortran Note:
1540:    This routine is not supported in Fortran.

1542:    Level: intermediate

1544: .seealso: VecGetArray(), VecRestoreArrays()
1545: @*/
1546: PetscErrorCode  VecGetArrays(const Vec x[],PetscInt n,PetscScalar **a[])
1547: {
1549:   PetscInt       i;
1550:   PetscScalar    **q;

1556:   if (n <= 0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Must get at least one array n = %D",n);
1557:   PetscMalloc1(n,&q);
1558:   for (i=0; i<n; ++i) {
1559:     VecGetArray(x[i],&q[i]);
1560:   }
1561:   *a = q;
1562:   return(0);
1563: }

1567: /*@C
1568:    VecRestoreArrays - Restores a group of vectors after VecGetArrays()
1569:    has been called.

1571:    Logically Collective on Vec

1573:    Input Parameters:
1574: +  x - the vector
1575: .  n - the number of vectors
1576: -  a - location of pointer to arrays obtained from VecGetArrays()

1578:    Notes:
1579:    For regular PETSc vectors this routine does not involve any copies. For
1580:    any special vectors that do not store local vector data in a contiguous
1581:    array, this routine will copy the data back into the underlying
1582:    vector data structure from the arrays obtained with VecGetArrays().

1584:    Fortran Note:
1585:    This routine is not supported in Fortran.

1587:    Level: intermediate

1589: .seealso: VecGetArrays(), VecRestoreArray()
1590: @*/
1591: PetscErrorCode  VecRestoreArrays(const Vec x[],PetscInt n,PetscScalar **a[])
1592: {
1594:   PetscInt       i;
1595:   PetscScalar    **q = *a;


1602:   for (i=0; i<n; ++i) {
1603:     VecRestoreArray(x[i],&q[i]);
1604:   }
1605:   PetscFree(q);
1606:   return(0);
1607: }

1611: /*@C
1612:    VecRestoreArray - Restores a vector after VecGetArray() has been called.

1614:    Logically Collective on Vec

1616:    Input Parameters:
1617: +  x - the vector
1618: -  a - location of pointer to array obtained from VecGetArray()

1620:    Level: beginner

1622:    Notes:
1623:    For regular PETSc vectors this routine does not involve any copies. For
1624:    any special vectors that do not store local vector data in a contiguous
1625:    array, this routine will copy the data back into the underlying
1626:    vector data structure from the array obtained with VecGetArray().

1628:    This routine actually zeros out the a pointer. This is to prevent accidental
1629:    us of the array after it has been restored. If you pass null for a it will
1630:    not zero the array pointer a.

1632:    Fortran Note:
1633:    This routine is used differently from Fortran 77
1634: $    Vec         x
1635: $    PetscScalar x_array(1)
1636: $    PetscOffset i_x
1637: $    PetscErrorCode ierr
1638: $       call VecGetArray(x,x_array,i_x,ierr)
1639: $
1640: $   Access first local entry in vector with
1641: $      value = x_array(i_x + 1)
1642: $
1643: $      ...... other code
1644: $       call VecRestoreArray(x,x_array,i_x,ierr)

1646:    See the Fortran chapter of the users manual and
1647:    petsc/src/snes/examples/tutorials/ex5f.F for details.
1648:    For Fortran 90 see VecRestoreArrayF90()

1650: .seealso: VecGetArray(), VecRestoreArrayRead(), VecRestoreArrays(), VecRestoreArrayF90(), VecPlaceArray(), VecRestoreArray2d()
1651: @*/
1652: PetscErrorCode VecRestoreArray(Vec x,PetscScalar **a)
1653: {

1658:   if (x->petscnative) {
1659: #if defined(PETSC_HAVE_CUSP)
1660:     x->valid_GPU_array = PETSC_CUSP_CPU;
1661: #endif
1662: #if defined(PETSC_HAVE_VIENNACL)
1663:     x->valid_GPU_array = PETSC_VIENNACL_CPU;
1664: #endif
1665:   } else {
1666:     (*x->ops->restorearray)(x,a);
1667:   }
1668:   if (a) *a = NULL;
1669:   PetscObjectStateIncrease((PetscObject)x);
1670:   return(0);
1671: }

1675: /*@C
1676:    VecRestoreArrayRead - Restore array obtained with VecGetArrayRead()

1678:    Not Collective

1680:    Input Parameters:
1681: +  vec - the vector
1682: -  array - the array

1684:    Level: beginner

1686: .seealso: VecGetArray(), VecRestoreArray()
1687: @*/
1688: PetscErrorCode VecRestoreArrayRead(Vec x,const PetscScalar **a)
1689: {

1694:   if (x->petscnative) {
1695: #if defined(PETSC_HAVE_VIENNACL)
1696:     x->valid_GPU_array = PETSC_VIENNACL_CPU;
1697: #endif
1698:   } else if (x->ops->restorearrayread) {
1699:     (*x->ops->restorearrayread)(x,a);
1700:   } else {
1701:     (*x->ops->restorearray)(x,(PetscScalar**)a);
1702:   }
1703:   if (a) *a = NULL;
1704:   return(0);
1705: }

1709: /*@
1710:    VecPlaceArray - Allows one to replace the array in a vector with an
1711:    array provided by the user. This is useful to avoid copying an array
1712:    into a vector.

1714:    Not Collective

1716:    Input Parameters:
1717: +  vec - the vector
1718: -  array - the array

1720:    Notes:
1721:    You can return to the original array with a call to VecResetArray()

1723:    Level: developer

1725: .seealso: VecGetArray(), VecRestoreArray(), VecReplaceArray(), VecResetArray()

1727: @*/
1728: PetscErrorCode  VecPlaceArray(Vec vec,const PetscScalar array[])
1729: {

1736:   if (vec->ops->placearray) {
1737:     (*vec->ops->placearray)(vec,array);
1738:   } else SETERRQ(PetscObjectComm((PetscObject)vec),PETSC_ERR_SUP,"Cannot place array in this type of vector");
1739:   PetscObjectStateIncrease((PetscObject)vec);
1740:   return(0);
1741: }

1745: /*@C
1746:    VecReplaceArray - Allows one to replace the array in a vector with an
1747:    array provided by the user. This is useful to avoid copying an array
1748:    into a vector.

1750:    Not Collective

1752:    Input Parameters:
1753: +  vec - the vector
1754: -  array - the array

1756:    Notes:
1757:    This permanently replaces the array and frees the memory associated
1758:    with the old array.

1760:    The memory passed in MUST be obtained with PetscMalloc() and CANNOT be
1761:    freed by the user. It will be freed when the vector is destroy.

1763:    Not supported from Fortran

1765:    Level: developer

1767: .seealso: VecGetArray(), VecRestoreArray(), VecPlaceArray(), VecResetArray()

1769: @*/
1770: PetscErrorCode  VecReplaceArray(Vec vec,const PetscScalar array[])
1771: {

1777:   if (vec->ops->replacearray) {
1778:     (*vec->ops->replacearray)(vec,array);
1779:   } else SETERRQ(PetscObjectComm((PetscObject)vec),PETSC_ERR_SUP,"Cannot replace array in this type of vector");
1780:   PetscObjectStateIncrease((PetscObject)vec);
1781:   return(0);
1782: }

1784: /*MC
1785:     VecDuplicateVecsF90 - Creates several vectors of the same type as an existing vector
1786:     and makes them accessible via a Fortran90 pointer.

1788:     Synopsis:
1789:     VecDuplicateVecsF90(Vec x,PetscInt n,{Vec, pointer :: y(:)},integer ierr)

1791:     Collective on Vec

1793:     Input Parameters:
1794: +   x - a vector to mimic
1795: -   n - the number of vectors to obtain

1797:     Output Parameters:
1798: +   y - Fortran90 pointer to the array of vectors
1799: -   ierr - error code

1801:     Example of Usage:
1802: .vb
1803:     Vec x
1804:     Vec, pointer :: y(:)
1805:     ....
1806:     call VecDuplicateVecsF90(x,2,y,ierr)
1807:     call VecSet(y(2),alpha,ierr)
1808:     call VecSet(y(2),alpha,ierr)
1809:     ....
1810:     call VecDestroyVecsF90(2,y,ierr)
1811: .ve

1813:     Notes:
1814:     Not yet supported for all F90 compilers

1816:     Use VecDestroyVecsF90() to free the space.

1818:     Level: beginner

1820: .seealso:  VecDestroyVecsF90(), VecDuplicateVecs()

1822: M*/

1824: /*MC
1825:     VecRestoreArrayF90 - Restores a vector to a usable state after a call to
1826:     VecGetArrayF90().

1828:     Synopsis:
1829:     VecRestoreArrayF90(Vec x,{Scalar, pointer :: xx_v(:)},integer ierr)

1831:     Logically Collective on Vec

1833:     Input Parameters:
1834: +   x - vector
1835: -   xx_v - the Fortran90 pointer to the array

1837:     Output Parameter:
1838: .   ierr - error code

1840:     Example of Usage:
1841: .vb
1842:     PetscScalar, pointer :: xx_v(:)
1843:     ....
1844:     call VecGetArrayF90(x,xx_v,ierr)
1845:     a = xx_v(3)
1846:     call VecRestoreArrayF90(x,xx_v,ierr)
1847: .ve

1849:     Level: beginner

1851: .seealso:  VecGetArrayF90(), VecGetArray(), VecRestoreArray(), UsingFortran

1853: M*/

1855: /*MC
1856:     VecDestroyVecsF90 - Frees a block of vectors obtained with VecDuplicateVecsF90().

1858:     Synopsis:
1859:     VecDestroyVecsF90(PetscInt n,{Vec, pointer :: x(:)},PetscErrorCode ierr)

1861:     Collective on Vec

1863:     Input Parameters:
1864: +   n - the number of vectors previously obtained
1865: -   x - pointer to array of vector pointers

1867:     Output Parameter:
1868: .   ierr - error code

1870:     Notes:
1871:     Not yet supported for all F90 compilers

1873:     Level: beginner

1875: .seealso:  VecDestroyVecs(), VecDuplicateVecsF90()

1877: M*/

1879: /*MC
1880:     VecGetArrayF90 - Accesses a vector array from Fortran90. For default PETSc
1881:     vectors, VecGetArrayF90() returns a pointer to the local data array. Otherwise,
1882:     this routine is implementation dependent. You MUST call VecRestoreArrayF90()
1883:     when you no longer need access to the array.

1885:     Synopsis:
1886:     VecGetArrayF90(Vec x,{Scalar, pointer :: xx_v(:)},integer ierr)

1888:     Logically Collective on Vec

1890:     Input Parameter:
1891: .   x - vector

1893:     Output Parameters:
1894: +   xx_v - the Fortran90 pointer to the array
1895: -   ierr - error code

1897:     Example of Usage:
1898: .vb
1899:     PetscScalar, pointer :: xx_v(:)
1900:     ....
1901:     call VecGetArrayF90(x,xx_v,ierr)
1902:     a = xx_v(3)
1903:     call VecRestoreArrayF90(x,xx_v,ierr)
1904: .ve

1906:     Level: beginner

1908: .seealso:  VecRestoreArrayF90(), VecGetArray(), VecRestoreArray(), UsingFortran

1910: M*/


1915: /*@C
1916:    VecGetArray2d - Returns a pointer to a 2d contiguous array that contains this
1917:    processor's portion of the vector data.  You MUST call VecRestoreArray2d()
1918:    when you no longer need access to the array.

1920:    Logically Collective

1922:    Input Parameter:
1923: +  x - the vector
1924: .  m - first dimension of two dimensional array
1925: .  n - second dimension of two dimensional array
1926: .  mstart - first index you will use in first coordinate direction (often 0)
1927: -  nstart - first index in the second coordinate direction (often 0)

1929:    Output Parameter:
1930: .  a - location to put pointer to the array

1932:    Level: developer

1934:   Notes:
1935:    For a vector obtained from DMCreateLocalVector() mstart and nstart are likely
1936:    obtained from the corner indices obtained from DMDAGetGhostCorners() while for
1937:    DMCreateGlobalVector() they are the corner indices from DMDAGetCorners(). In both cases
1938:    the arguments from DMDAGet[Ghost]Corners() are reversed in the call to VecGetArray2d().

1940:    For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

1942:    Concepts: vector^accessing local values as 2d array

1944: .seealso: VecGetArray(), VecRestoreArray(), VecGetArrays(), VecGetArrayF90(), VecPlaceArray(),
1945:           VecRestoreArray2d(), DMDAVecGetArray(), DMDAVecRestoreArray(), VecGetArray3d(), VecRestoreArray3d(),
1946:           VecGetArray1d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d()
1947: @*/
1948: PetscErrorCode  VecGetArray2d(Vec x,PetscInt m,PetscInt n,PetscInt mstart,PetscInt nstart,PetscScalar **a[])
1949: {
1951:   PetscInt       i,N;
1952:   PetscScalar    *aa;

1958:   VecGetLocalSize(x,&N);
1959:   if (m*n != N) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Local array size %D does not match 2d array dimensions %D by %D",N,m,n);
1960:   VecGetArray(x,&aa);

1962:   PetscMalloc1(m,a);
1963:   for (i=0; i<m; i++) (*a)[i] = aa + i*n - nstart;
1964:   *a -= mstart;
1965:   return(0);
1966: }

1970: /*@C
1971:    VecRestoreArray2d - Restores a vector after VecGetArray2d() has been called.

1973:    Logically Collective

1975:    Input Parameters:
1976: +  x - the vector
1977: .  m - first dimension of two dimensional array
1978: .  n - second dimension of the two dimensional array
1979: .  mstart - first index you will use in first coordinate direction (often 0)
1980: .  nstart - first index in the second coordinate direction (often 0)
1981: -  a - location of pointer to array obtained from VecGetArray2d()

1983:    Level: developer

1985:    Notes:
1986:    For regular PETSc vectors this routine does not involve any copies. For
1987:    any special vectors that do not store local vector data in a contiguous
1988:    array, this routine will copy the data back into the underlying
1989:    vector data structure from the array obtained with VecGetArray().

1991:    This routine actually zeros out the a pointer.

1993: .seealso: VecGetArray(), VecRestoreArray(), VecRestoreArrays(), VecRestoreArrayF90(), VecPlaceArray(),
1994:           VecGetArray2d(), VecGetArray3d(), VecRestoreArray3d(), DMDAVecGetArray(), DMDAVecRestoreArray()
1995:           VecGetArray1d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d()
1996: @*/
1997: PetscErrorCode  VecRestoreArray2d(Vec x,PetscInt m,PetscInt n,PetscInt mstart,PetscInt nstart,PetscScalar **a[])
1998: {
2000:   void           *dummy;

2006:   dummy = (void*)(*a + mstart);
2007:   PetscFree(dummy);
2008:   VecRestoreArray(x,NULL);
2009:   return(0);
2010: }

2014: /*@C
2015:    VecGetArray1d - Returns a pointer to a 1d contiguous array that contains this
2016:    processor's portion of the vector data.  You MUST call VecRestoreArray1d()
2017:    when you no longer need access to the array.

2019:    Logically Collective

2021:    Input Parameter:
2022: +  x - the vector
2023: .  m - first dimension of two dimensional array
2024: -  mstart - first index you will use in first coordinate direction (often 0)

2026:    Output Parameter:
2027: .  a - location to put pointer to the array

2029:    Level: developer

2031:   Notes:
2032:    For a vector obtained from DMCreateLocalVector() mstart are likely
2033:    obtained from the corner indices obtained from DMDAGetGhostCorners() while for
2034:    DMCreateGlobalVector() they are the corner indices from DMDAGetCorners().

2036:    For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2038: .seealso: VecGetArray(), VecRestoreArray(), VecGetArrays(), VecGetArrayF90(), VecPlaceArray(),
2039:           VecRestoreArray2d(), DMDAVecGetArray(), DMDAVecRestoreArray(), VecGetArray3d(), VecRestoreArray3d(),
2040:           VecGetArray2d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d()
2041: @*/
2042: PetscErrorCode  VecGetArray1d(Vec x,PetscInt m,PetscInt mstart,PetscScalar *a[])
2043: {
2045:   PetscInt       N;

2051:   VecGetLocalSize(x,&N);
2052:   if (m != N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local array size %D does not match 1d array dimensions %D",N,m);
2053:   VecGetArray(x,a);
2054:   *a  -= mstart;
2055:   return(0);
2056: }

2060: /*@C
2061:    VecRestoreArray1d - Restores a vector after VecGetArray1d() has been called.

2063:    Logically Collective

2065:    Input Parameters:
2066: +  x - the vector
2067: .  m - first dimension of two dimensional array
2068: .  mstart - first index you will use in first coordinate direction (often 0)
2069: -  a - location of pointer to array obtained from VecGetArray21()

2071:    Level: developer

2073:    Notes:
2074:    For regular PETSc vectors this routine does not involve any copies. For
2075:    any special vectors that do not store local vector data in a contiguous
2076:    array, this routine will copy the data back into the underlying
2077:    vector data structure from the array obtained with VecGetArray1d().

2079:    This routine actually zeros out the a pointer.

2081:    Concepts: vector^accessing local values as 1d array

2083: .seealso: VecGetArray(), VecRestoreArray(), VecRestoreArrays(), VecRestoreArrayF90(), VecPlaceArray(),
2084:           VecGetArray2d(), VecGetArray3d(), VecRestoreArray3d(), DMDAVecGetArray(), DMDAVecRestoreArray()
2085:           VecGetArray1d(), VecRestoreArray2d(), VecGetArray4d(), VecRestoreArray4d()
2086: @*/
2087: PetscErrorCode  VecRestoreArray1d(Vec x,PetscInt m,PetscInt mstart,PetscScalar *a[])
2088: {

2094:   VecRestoreArray(x,NULL);
2095:   return(0);
2096: }


2101: /*@C
2102:    VecGetArray3d - Returns a pointer to a 3d contiguous array that contains this
2103:    processor's portion of the vector data.  You MUST call VecRestoreArray3d()
2104:    when you no longer need access to the array.

2106:    Logically Collective

2108:    Input Parameter:
2109: +  x - the vector
2110: .  m - first dimension of three dimensional array
2111: .  n - second dimension of three dimensional array
2112: .  p - third dimension of three dimensional array
2113: .  mstart - first index you will use in first coordinate direction (often 0)
2114: .  nstart - first index in the second coordinate direction (often 0)
2115: -  pstart - first index in the third coordinate direction (often 0)

2117:    Output Parameter:
2118: .  a - location to put pointer to the array

2120:    Level: developer

2122:   Notes:
2123:    For a vector obtained from DMCreateLocalVector() mstart, nstart, and pstart are likely
2124:    obtained from the corner indices obtained from DMDAGetGhostCorners() while for
2125:    DMCreateGlobalVector() they are the corner indices from DMDAGetCorners(). In both cases
2126:    the arguments from DMDAGet[Ghost]Corners() are reversed in the call to VecGetArray3d().

2128:    For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2130:    Concepts: vector^accessing local values as 3d array

2132: .seealso: VecGetArray(), VecRestoreArray(), VecGetArrays(), VecGetArrayF90(), VecPlaceArray(),
2133:           VecRestoreArray2d(), DMDAVecGetarray(), DMDAVecRestoreArray(), VecGetArray3d(), VecRestoreArray3d(),
2134:           VecGetArray1d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d()
2135: @*/
2136: PetscErrorCode  VecGetArray3d(Vec x,PetscInt m,PetscInt n,PetscInt p,PetscInt mstart,PetscInt nstart,PetscInt pstart,PetscScalar ***a[])
2137: {
2139:   PetscInt       i,N,j;
2140:   PetscScalar    *aa,**b;

2146:   VecGetLocalSize(x,&N);
2147:   if (m*n*p != N) SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Local array size %D does not match 3d array dimensions %D by %D by %D",N,m,n,p);
2148:   VecGetArray(x,&aa);

2150:   PetscMalloc1(m*sizeof(PetscScalar**)+m*n,a);
2151:   b    = (PetscScalar**)((*a) + m);
2152:   for (i=0; i<m; i++) (*a)[i] = b + i*n - nstart;
2153:   for (i=0; i<m; i++)
2154:     for (j=0; j<n; j++)
2155:       b[i*n+j] = aa + i*n*p + j*p - pstart;

2157:   *a -= mstart;
2158:   return(0);
2159: }

2163: /*@C
2164:    VecRestoreArray3d - Restores a vector after VecGetArray3d() has been called.

2166:    Logically Collective

2168:    Input Parameters:
2169: +  x - the vector
2170: .  m - first dimension of three dimensional array
2171: .  n - second dimension of the three dimensional array
2172: .  p - third dimension of the three dimensional array
2173: .  mstart - first index you will use in first coordinate direction (often 0)
2174: .  nstart - first index in the second coordinate direction (often 0)
2175: .  pstart - first index in the third coordinate direction (often 0)
2176: -  a - location of pointer to array obtained from VecGetArray3d()

2178:    Level: developer

2180:    Notes:
2181:    For regular PETSc vectors this routine does not involve any copies. For
2182:    any special vectors that do not store local vector data in a contiguous
2183:    array, this routine will copy the data back into the underlying
2184:    vector data structure from the array obtained with VecGetArray().

2186:    This routine actually zeros out the a pointer.

2188: .seealso: VecGetArray(), VecRestoreArray(), VecRestoreArrays(), VecRestoreArrayF90(), VecPlaceArray(),
2189:           VecGetArray2d(), VecGetArray3d(), VecRestoreArray3d(), DMDAVecGetArray(), DMDAVecRestoreArray()
2190:           VecGetArray1d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d(), VecGet
2191: @*/
2192: PetscErrorCode  VecRestoreArray3d(Vec x,PetscInt m,PetscInt n,PetscInt p,PetscInt mstart,PetscInt nstart,PetscInt pstart,PetscScalar ***a[])
2193: {
2195:   void           *dummy;

2201:   dummy = (void*)(*a + mstart);
2202:   PetscFree(dummy);
2203:   VecRestoreArray(x,NULL);
2204:   return(0);
2205: }

2209: /*@C
2210:    VecGetArray4d - Returns a pointer to a 4d contiguous array that contains this
2211:    processor's portion of the vector data.  You MUST call VecRestoreArray4d()
2212:    when you no longer need access to the array.

2214:    Logically Collective

2216:    Input Parameter:
2217: +  x - the vector
2218: .  m - first dimension of four dimensional array
2219: .  n - second dimension of four dimensional array
2220: .  p - third dimension of four dimensional array
2221: .  q - fourth dimension of four dimensional array
2222: .  mstart - first index you will use in first coordinate direction (often 0)
2223: .  nstart - first index in the second coordinate direction (often 0)
2224: .  pstart - first index in the third coordinate direction (often 0)
2225: -  qstart - first index in the fourth coordinate direction (often 0)

2227:    Output Parameter:
2228: .  a - location to put pointer to the array

2230:    Level: beginner

2232:   Notes:
2233:    For a vector obtained from DMCreateLocalVector() mstart, nstart, and pstart are likely
2234:    obtained from the corner indices obtained from DMDAGetGhostCorners() while for
2235:    DMCreateGlobalVector() they are the corner indices from DMDAGetCorners(). In both cases
2236:    the arguments from DMDAGet[Ghost]Corners() are reversed in the call to VecGetArray3d().

2238:    For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.

2240:    Concepts: vector^accessing local values as 3d array

2242: .seealso: VecGetArray(), VecRestoreArray(), VecGetArrays(), VecGetArrayF90(), VecPlaceArray(),
2243:           VecRestoreArray2d(), DMDAVecGetarray(), DMDAVecRestoreArray(), VecGetArray3d(), VecRestoreArray3d(),
2244:           VecGetArray1d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d()
2245: @*/
2246: PetscErrorCode  VecGetArray4d(Vec x,PetscInt m,PetscInt n,PetscInt p,PetscInt q,PetscInt mstart,PetscInt nstart,PetscInt pstart,PetscInt qstart,PetscScalar ****a[])
2247: {
2249:   PetscInt       i,N,j,k;
2250:   PetscScalar    *aa,***b,**c;

2256:   VecGetLocalSize(x,&N);
2257:   if (m*n*p*q != N) SETERRQ5(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Local array size %D does not match 4d array dimensions %D by %D by %D by %D",N,m,n,p,q);
2258:   VecGetArray(x,&aa);

2260:   PetscMalloc1(m*sizeof(PetscScalar***)+m*n*sizeof(PetscScalar**)+m*n*p,a);
2261:   b    = (PetscScalar***)((*a) + m);
2262:   c    = (PetscScalar**)(b + m*n);
2263:   for (i=0; i<m; i++) (*a)[i] = b + i*n - nstart;
2264:   for (i=0; i<m; i++)
2265:     for (j=0; j<n; j++)
2266:       b[i*n+j] = c + i*n*p + j*p - pstart;
2267:   for (i=0; i<m; i++)
2268:     for (j=0; j<n; j++)
2269:       for (k=0; k<p; k++)
2270:         c[i*n*p+j*p+k] = aa + i*n*p*q + j*p*q + k*q - qstart;
2271:   *a -= mstart;
2272:   return(0);
2273: }

2277: /*@C
2278:    VecRestoreArray4d - Restores a vector after VecGetArray3d() has been called.

2280:    Logically Collective

2282:    Input Parameters:
2283: +  x - the vector
2284: .  m - first dimension of four dimensional array
2285: .  n - second dimension of the four dimensional array
2286: .  p - third dimension of the four dimensional array
2287: .  q - fourth dimension of the four dimensional array
2288: .  mstart - first index you will use in first coordinate direction (often 0)
2289: .  nstart - first index in the second coordinate direction (often 0)
2290: .  pstart - first index in the third coordinate direction (often 0)
2291: .  qstart - first index in the fourth coordinate direction (often 0)
2292: -  a - location of pointer to array obtained from VecGetArray4d()

2294:    Level: beginner

2296:    Notes:
2297:    For regular PETSc vectors this routine does not involve any copies. For
2298:    any special vectors that do not store local vector data in a contiguous
2299:    array, this routine will copy the data back into the underlying
2300:    vector data structure from the array obtained with VecGetArray().

2302:    This routine actually zeros out the a pointer.

2304: .seealso: VecGetArray(), VecRestoreArray(), VecRestoreArrays(), VecRestoreArrayF90(), VecPlaceArray(),
2305:           VecGetArray2d(), VecGetArray3d(), VecRestoreArray3d(), DMDAVecGetArray(), DMDAVecRestoreArray()
2306:           VecGetArray1d(), VecRestoreArray1d(), VecGetArray4d(), VecRestoreArray4d(), VecGet
2307: @*/
2308: PetscErrorCode  VecRestoreArray4d(Vec x,PetscInt m,PetscInt n,PetscInt p,PetscInt q,PetscInt mstart,PetscInt nstart,PetscInt pstart,PetscInt qstart,PetscScalar ****a[])
2309: {
2311:   void           *dummy;

2317:   dummy = (void*)(*a + mstart);
2318:   PetscFree(dummy);
2319:   VecRestoreArray(x,NULL);
2320:   return(0);
2321: }