Actual source code: bvbasic.c

slepc-3.21.0 2024-03-30
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain

  6:    This file is part of SLEPc.
  7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
  8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  9: */
 10: /*
 11:    Basic BV routines
 12: */

 14: #include <slepc/private/bvimpl.h>

 16: PetscBool         BVRegisterAllCalled = PETSC_FALSE;
 17: PetscFunctionList BVList = NULL;

 19: /*@C
 20:    BVSetType - Selects the type for the BV object.

 22:    Logically Collective

 24:    Input Parameters:
 25: +  bv   - the basis vectors context
 26: -  type - a known type

 28:    Options Database Key:
 29: .  -bv_type <type> - Sets BV type

 31:    Level: intermediate

 33: .seealso: BVGetType()
 34: @*/
 35: PetscErrorCode BVSetType(BV bv,BVType type)
 36: {
 37:   PetscErrorCode (*r)(BV);
 38:   PetscBool      match;

 40:   PetscFunctionBegin;
 42:   PetscAssertPointer(type,2);

 44:   PetscCall(PetscObjectTypeCompare((PetscObject)bv,type,&match));
 45:   if (match) PetscFunctionReturn(PETSC_SUCCESS);
 46:   PetscCall(PetscStrcmp(type,BVTENSOR,&match));
 47:   PetscCheck(!match,PetscObjectComm((PetscObject)bv),PETSC_ERR_ORDER,"Use BVCreateTensor() to create a BV of type tensor");

 49:   PetscCall(PetscFunctionListFind(BVList,type,&r));
 50:   PetscCheck(r,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested BV type %s",type);

 52:   PetscTryTypeMethod(bv,destroy);
 53:   PetscCall(PetscMemzero(bv->ops,sizeof(struct _BVOps)));

 55:   PetscCall(PetscObjectChangeTypeName((PetscObject)bv,type));
 56:   if (bv->n < 0 && bv->N < 0) {
 57:     bv->ops->create = r;
 58:   } else {
 59:     PetscCall(PetscLogEventBegin(BV_Create,bv,0,0,0));
 60:     PetscCall((*r)(bv));
 61:     PetscCall(PetscLogEventEnd(BV_Create,bv,0,0,0));
 62:   }
 63:   PetscFunctionReturn(PETSC_SUCCESS);
 64: }

 66: /*@C
 67:    BVGetType - Gets the BV type name (as a string) from the BV context.

 69:    Not Collective

 71:    Input Parameter:
 72: .  bv - the basis vectors context

 74:    Output Parameter:
 75: .  type - name of the type of basis vectors

 77:    Level: intermediate

 79: .seealso: BVSetType()
 80: @*/
 81: PetscErrorCode BVGetType(BV bv,BVType *type)
 82: {
 83:   PetscFunctionBegin;
 85:   PetscAssertPointer(type,2);
 86:   *type = ((PetscObject)bv)->type_name;
 87:   PetscFunctionReturn(PETSC_SUCCESS);
 88: }

 90: /*@
 91:    BVSetSizes - Sets the local and global sizes, and the number of columns.

 93:    Collective

 95:    Input Parameters:
 96: +  bv - the basis vectors
 97: .  n  - the local size (or PETSC_DECIDE to have it set)
 98: .  N  - the global size (or PETSC_DECIDE)
 99: -  m  - the number of columns

101:    Notes:
102:    n and N cannot be both PETSC_DECIDE.
103:    If one processor calls this with N of PETSC_DECIDE then all processors must,
104:    otherwise the program will hang.

106:    Level: beginner

108: .seealso: BVSetSizesFromVec(), BVGetSizes(), BVResize()
109: @*/
110: PetscErrorCode BVSetSizes(BV bv,PetscInt n,PetscInt N,PetscInt m)
111: {
112:   PetscInt       ma;
113:   PetscMPIInt    size;

115:   PetscFunctionBegin;
119:   PetscCheck(N<0 || n<=N,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Local size %" PetscInt_FMT " cannot be larger than global size %" PetscInt_FMT,n,N);
120:   PetscCheck(m>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Number of columns %" PetscInt_FMT " must be positive",m);
121:   PetscCheck((bv->n<0 && bv->N<0) || (bv->n==n && bv->N==N),PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Cannot change/reset vector sizes to %" PetscInt_FMT " local %" PetscInt_FMT " global after previously setting them to %" PetscInt_FMT " local %" PetscInt_FMT " global",n,N,bv->n,bv->N);
122:   PetscCheck(bv->m<=0 || bv->m==m,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Cannot change the number of columns to %" PetscInt_FMT " after previously setting it to %" PetscInt_FMT "; use BVResize()",m,bv->m);
123:   PetscCheck(!bv->map,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Vector layout was already defined by a previous call to BVSetSizes/FromVec");
124:   bv->n = n;
125:   bv->N = N;
126:   bv->m = m;
127:   bv->k = m;
128:   /* create layout and get actual dimensions */
129:   PetscCall(PetscLayoutCreate(PetscObjectComm((PetscObject)bv),&bv->map));
130:   PetscCall(PetscLayoutSetSize(bv->map,bv->N));
131:   PetscCall(PetscLayoutSetLocalSize(bv->map,bv->n));
132:   PetscCall(PetscLayoutSetUp(bv->map));
133:   PetscCall(PetscLayoutGetSize(bv->map,&bv->N));
134:   PetscCall(PetscLayoutGetLocalSize(bv->map,&bv->n));
135:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)bv),&size));
136:   PetscCall(BVSetVecType(bv,(size==1)?VECSEQ:VECMPI));
137:   if (bv->matrix) {  /* check compatible dimensions of user-provided matrix */
138:     PetscCall(MatGetLocalSize(bv->matrix,&ma,NULL));
139:     PetscCheck(bv->n==ma,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Local dimension %" PetscInt_FMT " does not match that of matrix given at BVSetMatrix %" PetscInt_FMT,bv->n,ma);
140:   }
141:   if (bv->ops->create) {
142:     PetscCall(PetscLogEventBegin(BV_Create,bv,0,0,0));
143:     PetscUseTypeMethod(bv,create);
144:     PetscCall(PetscLogEventEnd(BV_Create,bv,0,0,0));
145:     bv->ops->create = NULL;
146:     bv->defersfo = PETSC_FALSE;
147:   }
148:   PetscFunctionReturn(PETSC_SUCCESS);
149: }

151: /*@
152:    BVSetSizesFromVec - Sets the local and global sizes, and the number of columns.
153:    Local and global sizes are specified indirectly by passing a template vector.

155:    Collective

157:    Input Parameters:
158: +  bv - the basis vectors
159: .  t  - the template vector
160: -  m  - the number of columns

162:    Level: beginner

164: .seealso: BVSetSizes(), BVGetSizes(), BVResize()
165: @*/
166: PetscErrorCode BVSetSizesFromVec(BV bv,Vec t,PetscInt m)
167: {
168:   PetscInt       ma;
169:   PetscLayout    map;
170:   VecType        vtype;

172:   PetscFunctionBegin;
175:   PetscCheckSameComm(bv,1,t,2);
177:   PetscCheck(m>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Number of columns %" PetscInt_FMT " must be positive",m);
178:   PetscCheck(!bv->map,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Vector layout was already defined by a previous call to BVSetSizes/FromVec");
179:   PetscCall(VecGetType(t,&vtype));
180:   PetscCall(BVSetVecType(bv,vtype));
181:   PetscCall(VecGetLayout(t,&map));
182:   PetscCall(PetscLayoutReference(map,&bv->map));
183:   PetscCall(VecGetSize(t,&bv->N));
184:   PetscCall(VecGetLocalSize(t,&bv->n));
185:   if (bv->matrix) {  /* check compatible dimensions of user-provided matrix */
186:     PetscCall(MatGetLocalSize(bv->matrix,&ma,NULL));
187:     PetscCheck(bv->n==ma,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Local dimension %" PetscInt_FMT " does not match that of matrix given at BVSetMatrix %" PetscInt_FMT,bv->n,ma);
188:   }
189:   bv->m = m;
190:   bv->k = m;
191:   if (bv->ops->create) {
192:     PetscUseTypeMethod(bv,create);
193:     bv->ops->create = NULL;
194:     bv->defersfo = PETSC_FALSE;
195:   }
196:   PetscFunctionReturn(PETSC_SUCCESS);
197: }

199: /*@
200:    BVGetSizes - Returns the local and global sizes, and the number of columns.

202:    Not Collective

204:    Input Parameter:
205: .  bv - the basis vectors

207:    Output Parameters:
208: +  n  - the local size
209: .  N  - the global size
210: -  m  - the number of columns

212:    Note:
213:    Normal usage requires that bv has already been given its sizes, otherwise
214:    the call fails. However, this function can also be used to determine if
215:    a BV object has been initialized completely (sizes and type). For this,
216:    call with n=NULL and N=NULL, then a return value of m=0 indicates that
217:    the BV object is not ready for use yet.

219:    Level: beginner

221: .seealso: BVSetSizes(), BVSetSizesFromVec()
222: @*/
223: PetscErrorCode BVGetSizes(BV bv,PetscInt *n,PetscInt *N,PetscInt *m)
224: {
225:   PetscFunctionBegin;
226:   if (!bv) {
227:     if (m && !n && !N) *m = 0;
228:     PetscFunctionReturn(PETSC_SUCCESS);
229:   }
231:   if (n || N) BVCheckSizes(bv,1);
232:   if (n) *n = bv->n;
233:   if (N) *N = bv->N;
234:   if (m) *m = bv->m;
235:   if (m && !n && !N && !((PetscObject)bv)->type_name) *m = 0;
236:   PetscFunctionReturn(PETSC_SUCCESS);
237: }

239: /*@
240:    BVSetNumConstraints - Set the number of constraints.

242:    Logically Collective

244:    Input Parameters:
245: +  V  - basis vectors
246: -  nc - number of constraints

248:    Notes:
249:    This function sets the number of constraints to nc and marks all remaining
250:    columns as regular. Normal user would call BVInsertConstraints() instead.

252:    If nc is smaller than the previously set value, then some of the constraints
253:    are discarded. In particular, using nc=0 removes all constraints preserving
254:    the content of regular columns.

256:    Level: developer

258: .seealso: BVInsertConstraints()
259: @*/
260: PetscErrorCode BVSetNumConstraints(BV V,PetscInt nc)
261: {
262:   PetscInt       total,diff,i;
263:   Vec            x,y;

265:   PetscFunctionBegin;
268:   PetscCheck(nc>=0,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_OUTOFRANGE,"Number of constraints (given %" PetscInt_FMT ") cannot be negative",nc);
270:   BVCheckSizes(V,1);
271:   PetscCheck(V->ci[0]==-V->nc-1 && V->ci[1]==-V->nc-1,PetscObjectComm((PetscObject)V),PETSC_ERR_SUP,"Cannot call BVSetNumConstraints after BVGetColumn");

273:   diff = nc-V->nc;
274:   if (!diff) PetscFunctionReturn(PETSC_SUCCESS);
275:   total = V->nc+V->m;
276:   PetscCheck(total-nc>0,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_OUTOFRANGE,"Not enough columns for the given nc value");
277:   if (diff<0) {  /* lessen constraints, shift contents of BV */
278:     for (i=0;i<V->m;i++) {
279:       PetscCall(BVGetColumn(V,i,&x));
280:       PetscCall(BVGetColumn(V,i+diff,&y));
281:       PetscCall(VecCopy(x,y));
282:       PetscCall(BVRestoreColumn(V,i,&x));
283:       PetscCall(BVRestoreColumn(V,i+diff,&y));
284:     }
285:   }
286:   V->nc = nc;
287:   V->ci[0] = -V->nc-1;
288:   V->ci[1] = -V->nc-1;
289:   V->m = total-nc;
290:   V->l = PetscMin(V->l,V->m);
291:   V->k = PetscMin(V->k,V->m);
292:   PetscCall(PetscObjectStateIncrease((PetscObject)V));
293:   PetscFunctionReturn(PETSC_SUCCESS);
294: }

296: /*@
297:    BVGetNumConstraints - Returns the number of constraints.

299:    Not Collective

301:    Input Parameter:
302: .  bv - the basis vectors

304:    Output Parameters:
305: .  nc - the number of constraints

307:    Level: advanced

309: .seealso: BVGetSizes(), BVInsertConstraints()
310: @*/
311: PetscErrorCode BVGetNumConstraints(BV bv,PetscInt *nc)
312: {
313:   PetscFunctionBegin;
315:   PetscAssertPointer(nc,2);
316:   *nc = bv->nc;
317:   PetscFunctionReturn(PETSC_SUCCESS);
318: }

320: /*@
321:    BVResize - Change the number of columns.

323:    Collective

325:    Input Parameters:
326: +  bv   - the basis vectors
327: .  m    - the new number of columns
328: -  copy - a flag indicating whether current values should be kept

330:    Note:
331:    Internal storage is reallocated. If the copy flag is set to true, then
332:    the contents are copied to the leading part of the new space.

334:    Level: advanced

336: .seealso: BVSetSizes(), BVSetSizesFromVec()
337: @*/
338: PetscErrorCode BVResize(BV bv,PetscInt m,PetscBool copy)
339: {
340:   PetscScalar       *array;
341:   const PetscScalar *omega;
342:   Vec               v;

344:   PetscFunctionBegin;
349:   PetscCheck(m>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Number of columns %" PetscInt_FMT " must be positive",m);
350:   PetscCheck(!bv->nc || bv->issplit,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot resize a BV with constraints");
351:   if (bv->m == m) PetscFunctionReturn(PETSC_SUCCESS);
352:   BVCheckOp(bv,1,resize);

354:   PetscCall(PetscLogEventBegin(BV_Create,bv,0,0,0));
355:   PetscUseTypeMethod(bv,resize,m,copy);
356:   PetscCall(VecDestroy(&bv->buffer));
357:   PetscCall(BVDestroy(&bv->cached));
358:   PetscCall(PetscFree2(bv->h,bv->c));
359:   if (bv->omega) {
360:     if (bv->cuda) {
361: #if defined(PETSC_HAVE_CUDA)
362:       PetscCall(VecCreateSeqCUDA(PETSC_COMM_SELF,m,&v));
363: #else
364:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_PLIB,"Something wrong happened");
365: #endif
366:     } else PetscCall(VecCreateSeq(PETSC_COMM_SELF,m,&v));
367:     if (copy) {
368:       PetscCall(VecGetArray(v,&array));
369:       PetscCall(VecGetArrayRead(bv->omega,&omega));
370:       PetscCall(PetscArraycpy(array,omega,PetscMin(m,bv->m)));
371:       PetscCall(VecRestoreArrayRead(bv->omega,&omega));
372:       PetscCall(VecRestoreArray(v,&array));
373:     } else PetscCall(VecSet(v,1.0));
374:     PetscCall(VecDestroy(&bv->omega));
375:     bv->omega = v;
376:   }
377:   bv->m = m;
378:   bv->k = PetscMin(bv->k,m);
379:   bv->l = PetscMin(bv->l,m);
380:   PetscCall(PetscLogEventEnd(BV_Create,bv,0,0,0));
381:   PetscCall(PetscObjectStateIncrease((PetscObject)bv));
382:   PetscFunctionReturn(PETSC_SUCCESS);
383: }

385: /*@
386:    BVSetActiveColumns - Specify the columns that will be involved in operations.

388:    Logically Collective

390:    Input Parameters:
391: +  bv - the basis vectors context
392: .  l  - number of leading columns
393: -  k  - number of active columns

395:    Notes:
396:    In operations such as BVMult() or BVDot(), only the first k columns are
397:    considered. This is useful when the BV is filled from left to right, so
398:    the last m-k columns do not have relevant information.

400:    Also in operations such as BVMult() or BVDot(), the first l columns are
401:    normally not included in the computation. See the manpage of each
402:    operation.

404:    In orthogonalization operations, the first l columns are treated
405:    differently, they participate in the orthogonalization but the computed
406:    coefficients are not stored.

408:    Level: intermediate

410: .seealso: BVGetActiveColumns(), BVSetSizes()
411: @*/
412: PetscErrorCode BVSetActiveColumns(BV bv,PetscInt l,PetscInt k)
413: {
414:   PetscFunctionBegin;
418:   BVCheckSizes(bv,1);
419:   if (PetscUnlikely(k==PETSC_DECIDE || k==PETSC_DEFAULT)) {
420:     bv->k = bv->m;
421:   } else {
422:     PetscCheck(k>=0 && k<=bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of k (%" PetscInt_FMT "). Must be between 0 and m (%" PetscInt_FMT ")",k,bv->m);
423:     bv->k = k;
424:   }
425:   if (PetscUnlikely(l==PETSC_DECIDE || l==PETSC_DEFAULT)) {
426:     bv->l = 0;
427:   } else {
428:     PetscCheck(l>=0 && l<=bv->k,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of l (%" PetscInt_FMT "). Must be between 0 and k (%" PetscInt_FMT ")",l,bv->k);
429:     bv->l = l;
430:   }
431:   PetscFunctionReturn(PETSC_SUCCESS);
432: }

434: /*@
435:    BVGetActiveColumns - Returns the current active dimensions.

437:    Not Collective

439:    Input Parameter:
440: .  bv - the basis vectors context

442:    Output Parameters:
443: +  l  - number of leading columns
444: -  k  - number of active columns

446:    Level: intermediate

448: .seealso: BVSetActiveColumns()
449: @*/
450: PetscErrorCode BVGetActiveColumns(BV bv,PetscInt *l,PetscInt *k)
451: {
452:   PetscFunctionBegin;
454:   if (l) *l = bv->l;
455:   if (k) *k = bv->k;
456:   PetscFunctionReturn(PETSC_SUCCESS);
457: }

459: /*@
460:    BVSetMatrix - Specifies the inner product to be used in orthogonalization.

462:    Collective

464:    Input Parameters:
465: +  bv    - the basis vectors context
466: .  B     - a symmetric matrix (may be NULL)
467: -  indef - a flag indicating if the matrix is indefinite

469:    Notes:
470:    This is used to specify a non-standard inner product, whose matrix
471:    representation is given by B. Then, all inner products required during
472:    orthogonalization are computed as (x,y)_B=y^H*B*x rather than the
473:    standard form (x,y)=y^H*x.

475:    Matrix B must be real symmetric (or complex Hermitian). A genuine inner
476:    product requires that B is also positive (semi-)definite. However, we
477:    also allow for an indefinite B (setting indef=PETSC_TRUE), in which
478:    case the orthogonalization uses an indefinite inner product.

480:    This affects operations BVDot(), BVNorm(), BVOrthogonalize(), and variants.

482:    Setting B=NULL has the same effect as if the identity matrix was passed.

484:    Level: advanced

486: .seealso: BVGetMatrix(), BVDot(), BVNorm(), BVOrthogonalize(), BVSetDefiniteTolerance()
487: @*/
488: PetscErrorCode BVSetMatrix(BV bv,Mat B,PetscBool indef)
489: {
490:   PetscInt       m,n;

492:   PetscFunctionBegin;
495:   if (B!=bv->matrix || (B && ((PetscObject)B)->id!=((PetscObject)bv->matrix)->id) || indef!=bv->indef) {
496:     if (B) {
498:       PetscCall(MatGetLocalSize(B,&m,&n));
499:       PetscCheck(m==n,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Matrix must be square");
500:       PetscCheck(!bv->m || bv->n==n,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Mismatching local dimension BV %" PetscInt_FMT ", Mat %" PetscInt_FMT,bv->n,n);
501:     }
502:     if (B) PetscCall(PetscObjectReference((PetscObject)B));
503:     PetscCall(MatDestroy(&bv->matrix));
504:     bv->matrix = B;
505:     bv->indef  = indef;
506:     PetscCall(PetscObjectStateIncrease((PetscObject)bv));
507:     if (bv->Bx) PetscCall(PetscObjectStateIncrease((PetscObject)bv->Bx));
508:     if (bv->cached) PetscCall(PetscObjectStateIncrease((PetscObject)bv->cached));
509:   }
510:   PetscFunctionReturn(PETSC_SUCCESS);
511: }

513: /*@
514:    BVGetMatrix - Retrieves the matrix representation of the inner product.

516:    Not Collective

518:    Input Parameter:
519: .  bv    - the basis vectors context

521:    Output Parameters:
522: +  B     - the matrix of the inner product (may be NULL)
523: -  indef - the flag indicating if the matrix is indefinite

525:    Level: advanced

527: .seealso: BVSetMatrix()
528: @*/
529: PetscErrorCode BVGetMatrix(BV bv,Mat *B,PetscBool *indef)
530: {
531:   PetscFunctionBegin;
533:   if (B)     *B     = bv->matrix;
534:   if (indef) *indef = bv->indef;
535:   PetscFunctionReturn(PETSC_SUCCESS);
536: }

538: /*@
539:    BVApplyMatrix - Multiplies a vector by the matrix representation of the
540:    inner product.

542:    Neighbor-wise Collective

544:    Input Parameters:
545: +  bv - the basis vectors context
546: -  x  - the vector

548:    Output Parameter:
549: .  y  - the result

551:    Note:
552:    If no matrix was specified this function copies the vector.

554:    Level: advanced

556: .seealso: BVSetMatrix(), BVApplyMatrixBV()
557: @*/
558: PetscErrorCode BVApplyMatrix(BV bv,Vec x,Vec y)
559: {
560:   PetscFunctionBegin;
564:   if (bv->matrix) {
565:     PetscCall(BV_IPMatMult(bv,x));
566:     PetscCall(VecCopy(bv->Bx,y));
567:   } else PetscCall(VecCopy(x,y));
568:   PetscFunctionReturn(PETSC_SUCCESS);
569: }

571: /*@
572:    BVApplyMatrixBV - Multiplies the BV vectors by the matrix representation
573:    of the inner product.

575:    Neighbor-wise Collective

577:    Input Parameter:
578: .  X - the basis vectors context

580:    Output Parameter:
581: .  Y - the basis vectors to store the result (optional)

583:    Note:
584:    This function computes Y = B*X, where B is the matrix given with
585:    BVSetMatrix(). This operation is computed as in BVMatMult().
586:    If no matrix was specified, then it just copies Y = X.

588:    If no Y is given, the result is stored internally in the cached BV.

590:    Level: developer

592: .seealso: BVSetMatrix(), BVApplyMatrix(), BVMatMult(), BVGetCachedBV()
593: @*/
594: PetscErrorCode BVApplyMatrixBV(BV X,BV Y)
595: {
596:   PetscFunctionBegin;
598:   if (Y) {
600:     if (X->matrix) PetscCall(BVMatMult(X,X->matrix,Y));
601:     else PetscCall(BVCopy(X,Y));
602:   } else PetscCall(BV_IPMatMultBV(X));
603:   PetscFunctionReturn(PETSC_SUCCESS);
604: }

606: /*@
607:    BVSetSignature - Sets the signature matrix to be used in orthogonalization.

609:    Logically Collective

611:    Input Parameters:
612: +  bv    - the basis vectors context
613: -  omega - a vector representing the diagonal of the signature matrix

615:    Note:
616:    The signature matrix Omega = V'*B*V is relevant only for an indefinite B.

618:    Level: developer

620: .seealso: BVSetMatrix(), BVGetSignature()
621: @*/
622: PetscErrorCode BVSetSignature(BV bv,Vec omega)
623: {
624:   PetscInt          i,n;
625:   const PetscScalar *pomega;
626:   PetscScalar       *intern;

628:   PetscFunctionBegin;
630:   BVCheckSizes(bv,1);

634:   PetscCall(VecGetSize(omega,&n));
635:   PetscCheck(n==bv->k,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Vec argument has %" PetscInt_FMT " elements, should be %" PetscInt_FMT,n,bv->k);
636:   PetscCall(BV_AllocateSignature(bv));
637:   if (bv->indef) {
638:     PetscCall(VecGetArrayRead(omega,&pomega));
639:     PetscCall(VecGetArray(bv->omega,&intern));
640:     for (i=0;i<n;i++) intern[bv->nc+i] = pomega[i];
641:     PetscCall(VecRestoreArray(bv->omega,&intern));
642:     PetscCall(VecRestoreArrayRead(omega,&pomega));
643:   } else PetscCall(PetscInfo(bv,"Ignoring signature because BV is not indefinite\n"));
644:   PetscCall(PetscObjectStateIncrease((PetscObject)bv));
645:   PetscFunctionReturn(PETSC_SUCCESS);
646: }

648: /*@
649:    BVGetSignature - Retrieves the signature matrix from last orthogonalization.

651:    Not Collective

653:    Input Parameter:
654: .  bv    - the basis vectors context

656:    Output Parameter:
657: .  omega - a vector representing the diagonal of the signature matrix

659:    Note:
660:    The signature matrix Omega = V'*B*V is relevant only for an indefinite B.

662:    Level: developer

664: .seealso: BVSetMatrix(), BVSetSignature()
665: @*/
666: PetscErrorCode BVGetSignature(BV bv,Vec omega)
667: {
668:   PetscInt          i,n;
669:   PetscScalar       *pomega;
670:   const PetscScalar *intern;

672:   PetscFunctionBegin;
674:   BVCheckSizes(bv,1);

678:   PetscCall(VecGetSize(omega,&n));
679:   PetscCheck(n==bv->k,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Vec argument has %" PetscInt_FMT " elements, should be %" PetscInt_FMT,n,bv->k);
680:   if (bv->indef && bv->omega) {
681:     PetscCall(VecGetArray(omega,&pomega));
682:     PetscCall(VecGetArrayRead(bv->omega,&intern));
683:     for (i=0;i<n;i++) pomega[i] = intern[bv->nc+i];
684:     PetscCall(VecRestoreArrayRead(bv->omega,&intern));
685:     PetscCall(VecRestoreArray(omega,&pomega));
686:   } else PetscCall(VecSet(omega,1.0));
687:   PetscFunctionReturn(PETSC_SUCCESS);
688: }

690: /*@
691:    BVSetBufferVec - Attach a vector object to be used as buffer space for
692:    several operations.

694:    Collective

696:    Input Parameters:
697: +  bv     - the basis vectors context)
698: -  buffer - the vector

700:    Notes:
701:    Use BVGetBufferVec() to retrieve the vector (for example, to free it
702:    at the end of the computations).

704:    The vector must be sequential of length (nc+m)*m, where m is the number
705:    of columns of bv and nc is the number of constraints.

707:    Level: developer

709: .seealso: BVGetBufferVec(), BVSetSizes(), BVGetNumConstraints()
710: @*/
711: PetscErrorCode BVSetBufferVec(BV bv,Vec buffer)
712: {
713:   PetscInt       ld,n;
714:   PetscMPIInt    size;

716:   PetscFunctionBegin;
719:   BVCheckSizes(bv,1);
720:   PetscCall(VecGetSize(buffer,&n));
721:   ld = bv->m+bv->nc;
722:   PetscCheck(n==ld*bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Buffer size must be %" PetscInt_FMT,ld*bv->m);
723:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)buffer),&size));
724:   PetscCheck(size==1,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Buffer must be a sequential vector");

726:   PetscCall(PetscObjectReference((PetscObject)buffer));
727:   PetscCall(VecDestroy(&bv->buffer));
728:   bv->buffer = buffer;
729:   PetscFunctionReturn(PETSC_SUCCESS);
730: }

732: /*@
733:    BVGetBufferVec - Obtain the buffer vector associated with the BV object.

735:    Collective

737:    Input Parameters:
738: .  bv - the basis vectors context

740:    Output Parameter:
741: .  buffer - vector

743:    Notes:
744:    The vector is created if not available previously. It is a sequential vector
745:    of length (nc+m)*m, where m is the number of columns of bv and nc is the number
746:    of constraints.

748:    Developer Notes:
749:    The buffer vector is viewed as a column-major matrix with leading dimension
750:    ld=nc+m, and m columns at most. In the most common usage, it has the structure
751: .vb
752:       | | C |
753:       |s|---|
754:       | | H |
755: .ve
756:    where H is an upper Hessenberg matrix of order m x (m-1), C contains coefficients
757:    related to orthogonalization against constraints (first nc rows), and s is the
758:    first column that contains scratch values computed during Gram-Schmidt
759:    orthogonalization. In particular, BVDotColumn() and BVMultColumn() use s to
760:    store the coefficients.

762:    Level: developer

764: .seealso: BVSetBufferVec(), BVSetSizes(), BVGetNumConstraints(), BVDotColumn(), BVMultColumn()
765: @*/
766: PetscErrorCode BVGetBufferVec(BV bv,Vec *buffer)
767: {
768:   PetscInt       ld;

770:   PetscFunctionBegin;
772:   PetscAssertPointer(buffer,2);
773:   BVCheckSizes(bv,1);
774:   if (!bv->buffer) {
775:     ld = bv->m+bv->nc;
776:     PetscCall(VecCreate(PETSC_COMM_SELF,&bv->buffer));
777:     PetscCall(VecSetSizes(bv->buffer,PETSC_DECIDE,ld*bv->m));
778:     PetscCall(VecSetType(bv->buffer,bv->vtype));
779:   }
780:   *buffer = bv->buffer;
781:   PetscFunctionReturn(PETSC_SUCCESS);
782: }

784: /*@
785:    BVSetRandomContext - Sets the PetscRandom object associated with the BV,
786:    to be used in operations that need random numbers.

788:    Collective

790:    Input Parameters:
791: +  bv   - the basis vectors context
792: -  rand - the random number generator context

794:    Level: advanced

796: .seealso: BVGetRandomContext(), BVSetRandom(), BVSetRandomNormal(), BVSetRandomColumn(), BVSetRandomCond()
797: @*/
798: PetscErrorCode BVSetRandomContext(BV bv,PetscRandom rand)
799: {
800:   PetscFunctionBegin;
803:   PetscCheckSameComm(bv,1,rand,2);
804:   PetscCall(PetscObjectReference((PetscObject)rand));
805:   PetscCall(PetscRandomDestroy(&bv->rand));
806:   bv->rand = rand;
807:   PetscFunctionReturn(PETSC_SUCCESS);
808: }

810: /*@
811:    BVGetRandomContext - Gets the PetscRandom object associated with the BV.

813:    Collective

815:    Input Parameter:
816: .  bv - the basis vectors context

818:    Output Parameter:
819: .  rand - the random number generator context

821:    Level: advanced

823: .seealso: BVSetRandomContext(), BVSetRandom(), BVSetRandomNormal(), BVSetRandomColumn(), BVSetRandomCond()
824: @*/
825: PetscErrorCode BVGetRandomContext(BV bv,PetscRandom* rand)
826: {
827:   PetscFunctionBegin;
829:   PetscAssertPointer(rand,2);
830:   if (!bv->rand) {
831:     PetscCall(PetscRandomCreate(PetscObjectComm((PetscObject)bv),&bv->rand));
832:     if (bv->cuda) PetscCall(PetscRandomSetType(bv->rand,PETSCCURAND));
833:     if (bv->sfocalled) PetscCall(PetscRandomSetFromOptions(bv->rand));
834:     if (bv->rrandom) {
835:       PetscCall(PetscRandomSetSeed(bv->rand,0x12345678));
836:       PetscCall(PetscRandomSeed(bv->rand));
837:     }
838:   }
839:   *rand = bv->rand;
840:   PetscFunctionReturn(PETSC_SUCCESS);
841: }

843: /*@
844:    BVSetFromOptions - Sets BV options from the options database.

846:    Collective

848:    Input Parameter:
849: .  bv - the basis vectors context

851:    Level: beginner

853: .seealso: BVSetOptionsPrefix()
854: @*/
855: PetscErrorCode BVSetFromOptions(BV bv)
856: {
857:   char               type[256];
858:   PetscBool          flg1,flg2,flg3,flg4;
859:   PetscReal          r;
860:   BVOrthogType       otype;
861:   BVOrthogRefineType orefine;
862:   BVOrthogBlockType  oblock;

864:   PetscFunctionBegin;
866:   PetscCall(BVRegisterAll());
867:   PetscObjectOptionsBegin((PetscObject)bv);
868:     PetscCall(PetscOptionsFList("-bv_type","Basis Vectors type","BVSetType",BVList,(char*)(((PetscObject)bv)->type_name?((PetscObject)bv)->type_name:BVMAT),type,sizeof(type),&flg1));
869:     if (flg1) PetscCall(BVSetType(bv,type));
870:     else if (!((PetscObject)bv)->type_name) PetscCall(BVSetType(bv,BVMAT));

872:     otype = bv->orthog_type;
873:     PetscCall(PetscOptionsEnum("-bv_orthog_type","Orthogonalization method","BVSetOrthogonalization",BVOrthogTypes,(PetscEnum)otype,(PetscEnum*)&otype,&flg1));
874:     orefine = bv->orthog_ref;
875:     PetscCall(PetscOptionsEnum("-bv_orthog_refine","Iterative refinement mode during orthogonalization","BVSetOrthogonalization",BVOrthogRefineTypes,(PetscEnum)orefine,(PetscEnum*)&orefine,&flg2));
876:     r = bv->orthog_eta;
877:     PetscCall(PetscOptionsReal("-bv_orthog_eta","Parameter of iterative refinement during orthogonalization","BVSetOrthogonalization",r,&r,&flg3));
878:     oblock = bv->orthog_block;
879:     PetscCall(PetscOptionsEnum("-bv_orthog_block","Block orthogonalization method","BVSetOrthogonalization",BVOrthogBlockTypes,(PetscEnum)oblock,(PetscEnum*)&oblock,&flg4));
880:     if (flg1 || flg2 || flg3 || flg4) PetscCall(BVSetOrthogonalization(bv,otype,orefine,r,oblock));

882:     PetscCall(PetscOptionsEnum("-bv_matmult","Method for BVMatMult","BVSetMatMultMethod",BVMatMultTypes,(PetscEnum)bv->vmm,(PetscEnum*)&bv->vmm,NULL));

884:     PetscCall(PetscOptionsReal("-bv_definite_tol","Tolerance for checking a definite inner product","BVSetDefiniteTolerance",r,&r,&flg1));
885:     if (flg1) PetscCall(BVSetDefiniteTolerance(bv,r));

887:     /* undocumented option to generate random vectors that are independent of the number of processes */
888:     PetscCall(PetscOptionsGetBool(NULL,NULL,"-bv_reproducible_random",&bv->rrandom,NULL));

890:     if (bv->ops->create) bv->defersfo = PETSC_TRUE;   /* defer call to setfromoptions */
891:     else PetscTryTypeMethod(bv,setfromoptions,PetscOptionsObject);
892:     PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)bv,PetscOptionsObject));
893:   PetscOptionsEnd();
894:   bv->sfocalled = PETSC_TRUE;
895:   PetscFunctionReturn(PETSC_SUCCESS);
896: }

898: /*@
899:    BVSetOrthogonalization - Specifies the method used for the orthogonalization of
900:    vectors (classical or modified Gram-Schmidt with or without refinement), and
901:    for the block-orthogonalization (simultaneous orthogonalization of a set of
902:    vectors).

904:    Logically Collective

906:    Input Parameters:
907: +  bv     - the basis vectors context
908: .  type   - the method of vector orthogonalization
909: .  refine - type of refinement
910: .  eta    - parameter for selective refinement
911: -  block  - the method of block orthogonalization

913:    Options Database Keys:
914: +  -bv_orthog_type <type> - Where <type> is cgs for Classical Gram-Schmidt orthogonalization
915:                          (default) or mgs for Modified Gram-Schmidt orthogonalization
916: .  -bv_orthog_refine <ref> - Where <ref> is one of never, ifneeded (default) or always
917: .  -bv_orthog_eta <eta> -  For setting the value of eta
918: -  -bv_orthog_block <block> - Where <block> is the block-orthogonalization method

920:    Notes:
921:    The default settings work well for most problems.

923:    The parameter eta should be a real value between 0 and 1 (or PETSC_DEFAULT).
924:    The value of eta is used only when the refinement type is "ifneeded".

926:    When using several processors, MGS is likely to result in bad scalability.

928:    If the method set for block orthogonalization is GS, then the computation
929:    is done column by column with the vector orthogonalization.

931:    Level: advanced

933: .seealso: BVOrthogonalizeColumn(), BVGetOrthogonalization(), BVOrthogType, BVOrthogRefineType, BVOrthogBlockType
934: @*/
935: PetscErrorCode BVSetOrthogonalization(BV bv,BVOrthogType type,BVOrthogRefineType refine,PetscReal eta,BVOrthogBlockType block)
936: {
937:   PetscFunctionBegin;
943:   switch (type) {
944:     case BV_ORTHOG_CGS:
945:     case BV_ORTHOG_MGS:
946:       bv->orthog_type = type;
947:       break;
948:     default:
949:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown orthogonalization type");
950:   }
951:   switch (refine) {
952:     case BV_ORTHOG_REFINE_NEVER:
953:     case BV_ORTHOG_REFINE_IFNEEDED:
954:     case BV_ORTHOG_REFINE_ALWAYS:
955:       bv->orthog_ref = refine;
956:       break;
957:     default:
958:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown refinement type");
959:   }
960:   if (eta == (PetscReal)PETSC_DEFAULT) {
961:     bv->orthog_eta = 0.7071;
962:   } else {
963:     PetscCheck(eta>0.0 && eta<=1.0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Invalid eta value");
964:     bv->orthog_eta = eta;
965:   }
966:   switch (block) {
967:     case BV_ORTHOG_BLOCK_GS:
968:     case BV_ORTHOG_BLOCK_CHOL:
969:     case BV_ORTHOG_BLOCK_TSQR:
970:     case BV_ORTHOG_BLOCK_TSQRCHOL:
971:     case BV_ORTHOG_BLOCK_SVQB:
972:       bv->orthog_block = block;
973:       break;
974:     default:
975:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown block orthogonalization type");
976:   }
977:   PetscFunctionReturn(PETSC_SUCCESS);
978: }

980: /*@
981:    BVGetOrthogonalization - Gets the orthogonalization settings from the BV object.

983:    Not Collective

985:    Input Parameter:
986: .  bv - basis vectors context

988:    Output Parameters:
989: +  type   - the method of vector orthogonalization
990: .  refine - type of refinement
991: .  eta    - parameter for selective refinement
992: -  block  - the method of block orthogonalization

994:    Level: advanced

996: .seealso: BVOrthogonalizeColumn(), BVSetOrthogonalization(), BVOrthogType, BVOrthogRefineType, BVOrthogBlockType
997: @*/
998: PetscErrorCode BVGetOrthogonalization(BV bv,BVOrthogType *type,BVOrthogRefineType *refine,PetscReal *eta,BVOrthogBlockType *block)
999: {
1000:   PetscFunctionBegin;
1002:   if (type)   *type   = bv->orthog_type;
1003:   if (refine) *refine = bv->orthog_ref;
1004:   if (eta)    *eta    = bv->orthog_eta;
1005:   if (block)  *block  = bv->orthog_block;
1006:   PetscFunctionReturn(PETSC_SUCCESS);
1007: }

1009: /*@
1010:    BVSetMatMultMethod - Specifies the method used for the BVMatMult() operation.

1012:    Logically Collective

1014:    Input Parameters:
1015: +  bv     - the basis vectors context
1016: -  method - the method for the BVMatMult() operation

1018:    Options Database Keys:
1019: .  -bv_matmult <meth> - choose one of the methods: vecs, mat

1021:    Notes:
1022:    Allowed values are
1023: +  BV_MATMULT_VECS - perform a matrix-vector multiply per each column
1024: .  BV_MATMULT_MAT - carry out a Mat-Mat product with a dense matrix
1025: -  BV_MATMULT_MAT_SAVE - this case is deprecated

1027:    The default is BV_MATMULT_MAT except in the case of BVVECS.

1029:    Level: advanced

1031: .seealso: BVMatMult(), BVGetMatMultMethod(), BVMatMultType
1032: @*/
1033: PetscErrorCode BVSetMatMultMethod(BV bv,BVMatMultType method)
1034: {
1035:   PetscFunctionBegin;
1038:   switch (method) {
1039:     case BV_MATMULT_VECS:
1040:     case BV_MATMULT_MAT:
1041:       bv->vmm = method;
1042:       break;
1043:     case BV_MATMULT_MAT_SAVE:
1044:       PetscCall(PetscInfo(bv,"BV_MATMULT_MAT_SAVE is deprecated, using BV_MATMULT_MAT\n"));
1045:       bv->vmm = BV_MATMULT_MAT;
1046:       break;
1047:     default:
1048:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown matmult method");
1049:   }
1050:   PetscFunctionReturn(PETSC_SUCCESS);
1051: }

1053: /*@
1054:    BVGetMatMultMethod - Gets the method used for the BVMatMult() operation.

1056:    Not Collective

1058:    Input Parameter:
1059: .  bv - basis vectors context

1061:    Output Parameter:
1062: .  method - the method for the BVMatMult() operation

1064:    Level: advanced

1066: .seealso: BVMatMult(), BVSetMatMultMethod(), BVMatMultType
1067: @*/
1068: PetscErrorCode BVGetMatMultMethod(BV bv,BVMatMultType *method)
1069: {
1070:   PetscFunctionBegin;
1072:   PetscAssertPointer(method,2);
1073:   *method = bv->vmm;
1074:   PetscFunctionReturn(PETSC_SUCCESS);
1075: }

1077: /*@
1078:    BVGetColumn - Returns a Vec object that contains the entries of the
1079:    requested column of the basis vectors object.

1081:    Logically Collective

1083:    Input Parameters:
1084: +  bv - the basis vectors context
1085: -  j  - the index of the requested column

1087:    Output Parameter:
1088: .  v  - vector containing the jth column

1090:    Notes:
1091:    The returned Vec must be seen as a reference (not a copy) of the BV
1092:    column, that is, modifying the Vec will change the BV entries as well.

1094:    The returned Vec must not be destroyed. BVRestoreColumn() must be
1095:    called when it is no longer needed. At most, two columns can be fetched,
1096:    that is, this function can only be called twice before the corresponding
1097:    BVRestoreColumn() is invoked.

1099:    A negative index j selects the i-th constraint, where i=-j. Constraints
1100:    should not be modified.

1102:    Level: beginner

1104: .seealso: BVRestoreColumn(), BVInsertConstraints()
1105: @*/
1106: PetscErrorCode BVGetColumn(BV bv,PetscInt j,Vec *v)
1107: {
1108:   PetscInt       l;

1110:   PetscFunctionBegin;
1113:   BVCheckSizes(bv,1);
1114:   BVCheckOp(bv,1,getcolumn);
1116:   PetscCheck(j>=0 || -j<=bv->nc,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested constraint %" PetscInt_FMT " but only %" PetscInt_FMT " are available",-j,bv->nc);
1117:   PetscCheck(j<bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested column %" PetscInt_FMT " but only %" PetscInt_FMT " are available",j,bv->m);
1118:   PetscCheck(j!=bv->ci[0] && j!=bv->ci[1],PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Column %" PetscInt_FMT " already fetched in a previous call to BVGetColumn",j);
1119:   l = BVAvailableVec;
1120:   PetscCheck(l!=-1,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Too many requested columns; you must call BVRestoreColumn for one of the previously fetched columns");
1121:   PetscUseTypeMethod(bv,getcolumn,j,v);
1122:   bv->ci[l] = j;
1123:   PetscCall(PetscObjectStateGet((PetscObject)bv->cv[l],&bv->st[l]));
1124:   PetscCall(PetscObjectGetId((PetscObject)bv->cv[l],&bv->id[l]));
1125:   *v = bv->cv[l];
1126:   PetscFunctionReturn(PETSC_SUCCESS);
1127: }

1129: /*@
1130:    BVRestoreColumn - Restore a column obtained with BVGetColumn().

1132:    Logically Collective

1134:    Input Parameters:
1135: +  bv - the basis vectors context
1136: .  j  - the index of the column
1137: -  v  - vector obtained with BVGetColumn()

1139:    Note:
1140:    The arguments must match the corresponding call to BVGetColumn().

1142:    Level: beginner

1144: .seealso: BVGetColumn()
1145: @*/
1146: PetscErrorCode BVRestoreColumn(BV bv,PetscInt j,Vec *v)
1147: {
1148:   PetscObjectId    id;
1149:   PetscObjectState st;
1150:   PetscInt         l;

1152:   PetscFunctionBegin;
1155:   BVCheckSizes(bv,1);
1157:   PetscAssertPointer(v,3);
1159:   PetscCheck(j>=0 || -j<=bv->nc,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested constraint %" PetscInt_FMT " but only %" PetscInt_FMT " are available",-j,bv->nc);
1160:   PetscCheck(j<bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested column %" PetscInt_FMT " but only %" PetscInt_FMT " are available",j,bv->m);
1161:   PetscCheck(j==bv->ci[0] || j==bv->ci[1],PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Column %" PetscInt_FMT " has not been fetched with a call to BVGetColumn",j);
1162:   l = (j==bv->ci[0])? 0: 1;
1163:   PetscCall(PetscObjectGetId((PetscObject)*v,&id));
1164:   PetscCheck(id==bv->id[l],PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Argument 3 is not the same Vec that was obtained with BVGetColumn");
1165:   PetscCall(PetscObjectStateGet((PetscObject)*v,&st));
1166:   if (st!=bv->st[l]) PetscCall(PetscObjectStateIncrease((PetscObject)bv));
1167:   PetscUseTypeMethod(bv,restorecolumn,j,v);
1168:   bv->ci[l] = -bv->nc-1;
1169:   bv->st[l] = -1;
1170:   bv->id[l] = 0;
1171:   *v = NULL;
1172:   PetscFunctionReturn(PETSC_SUCCESS);
1173: }

1175: /*@C
1176:    BVGetArray - Returns a pointer to a contiguous array that contains this
1177:    processor's portion of the BV data.

1179:    Logically Collective

1181:    Input Parameters:
1182: .  bv - the basis vectors context

1184:    Output Parameter:
1185: .  a  - location to put pointer to the array

1187:    Notes:
1188:    BVRestoreArray() must be called when access to the array is no longer needed.
1189:    This operation may imply a data copy, for BV types that do not store
1190:    data contiguously in memory.

1192:    The pointer will normally point to the first entry of the first column,
1193:    but if the BV has constraints then these go before the regular columns.

1195:    Note that for manipulating the pointer to the BV array, one must take into
1196:    account the leading dimension, which might be different from the local
1197:    number of rows, see BVGetLeadingDimension().

1199:    Use BVGetArrayRead() for read-only access.

1201:    Level: advanced

1203: .seealso: BVRestoreArray(), BVInsertConstraints(), BVGetLeadingDimension(), BVGetArrayRead()
1204: @*/
1205: PetscErrorCode BVGetArray(BV bv,PetscScalar **a)
1206: {
1207:   PetscFunctionBegin;
1210:   BVCheckSizes(bv,1);
1211:   BVCheckOp(bv,1,getarray);
1212:   PetscUseTypeMethod(bv,getarray,a);
1213:   PetscFunctionReturn(PETSC_SUCCESS);
1214: }

1216: /*@C
1217:    BVRestoreArray - Restore the BV object after BVGetArray() has been called.

1219:    Logically Collective

1221:    Input Parameters:
1222: +  bv - the basis vectors context
1223: -  a  - location of pointer to array obtained from BVGetArray()

1225:    Note:
1226:    This operation may imply a data copy, for BV types that do not store
1227:    data contiguously in memory.

1229:    Level: advanced

1231: .seealso: BVGetColumn()
1232: @*/
1233: PetscErrorCode BVRestoreArray(BV bv,PetscScalar **a)
1234: {
1235:   PetscFunctionBegin;
1238:   BVCheckSizes(bv,1);
1239:   PetscTryTypeMethod(bv,restorearray,a);
1240:   if (a) *a = NULL;
1241:   PetscCall(PetscObjectStateIncrease((PetscObject)bv));
1242:   PetscFunctionReturn(PETSC_SUCCESS);
1243: }

1245: /*@C
1246:    BVGetArrayRead - Returns a read-only pointer to a contiguous array that
1247:    contains this processor's portion of the BV data.

1249:    Not Collective

1251:    Input Parameters:
1252: .  bv - the basis vectors context

1254:    Output Parameter:
1255: .  a  - location to put pointer to the array

1257:    Notes:
1258:    BVRestoreArrayRead() must be called when access to the array is no
1259:    longer needed. This operation may imply a data copy, for BV types that
1260:    do not store data contiguously in memory.

1262:    The pointer will normally point to the first entry of the first column,
1263:    but if the BV has constraints then these go before the regular columns.

1265:    Level: advanced

1267: .seealso: BVRestoreArray(), BVInsertConstraints(), BVGetLeadingDimension(), BVGetArray()
1268: @*/
1269: PetscErrorCode BVGetArrayRead(BV bv,const PetscScalar **a)
1270: {
1271:   PetscFunctionBegin;
1274:   BVCheckSizes(bv,1);
1275:   BVCheckOp(bv,1,getarrayread);
1276:   PetscUseTypeMethod(bv,getarrayread,a);
1277:   PetscFunctionReturn(PETSC_SUCCESS);
1278: }

1280: /*@C
1281:    BVRestoreArrayRead - Restore the BV object after BVGetArrayRead() has
1282:    been called.

1284:    Not Collective

1286:    Input Parameters:
1287: +  bv - the basis vectors context
1288: -  a  - location of pointer to array obtained from BVGetArrayRead()

1290:    Level: advanced

1292: .seealso: BVGetColumn()
1293: @*/
1294: PetscErrorCode BVRestoreArrayRead(BV bv,const PetscScalar **a)
1295: {
1296:   PetscFunctionBegin;
1299:   BVCheckSizes(bv,1);
1300:   PetscTryTypeMethod(bv,restorearrayread,a);
1301:   if (a) *a = NULL;
1302:   PetscFunctionReturn(PETSC_SUCCESS);
1303: }

1305: /*@
1306:    BVCreateVec - Creates a new Vec object with the same type and dimensions
1307:    as the columns of the basis vectors object.

1309:    Collective

1311:    Input Parameter:
1312: .  bv - the basis vectors context

1314:    Output Parameter:
1315: .  v  - the new vector

1317:    Note:
1318:    The user is responsible of destroying the returned vector.

1320:    Level: beginner

1322: .seealso: BVCreateMat(), BVCreateVecEmpty()
1323: @*/
1324: PetscErrorCode BVCreateVec(BV bv,Vec *v)
1325: {
1326:   PetscFunctionBegin;
1328:   BVCheckSizes(bv,1);
1329:   PetscAssertPointer(v,2);
1330:   PetscCall(VecCreate(PetscObjectComm((PetscObject)bv),v));
1331:   PetscCall(VecSetLayout(*v,bv->map));
1332:   PetscCall(VecSetType(*v,bv->vtype));
1333:   PetscCall(VecSetUp(*v));
1334:   PetscFunctionReturn(PETSC_SUCCESS);
1335: }

1337: /*@
1338:    BVCreateVecEmpty - Creates a new Vec object with the same type and dimensions
1339:    as the columns of the basis vectors object, but without internal array.

1341:    Collective

1343:    Input Parameter:
1344: .  bv - the basis vectors context

1346:    Output Parameter:
1347: .  v  - the new vector

1349:    Note:
1350:    This works as BVCreateVec(), but the new vector does not have the array allocated,
1351:    so the intended usage is with VecPlaceArray().

1353:    Level: developer

1355: .seealso: BVCreateVec()
1356: @*/
1357: PetscErrorCode BVCreateVecEmpty(BV bv,Vec *v)
1358: {
1359:   PetscBool  standard,cuda,mpi;
1360:   PetscInt   N,nloc,bs;

1362:   PetscFunctionBegin;
1364:   BVCheckSizes(bv,1);
1365:   PetscAssertPointer(v,2);

1367:   PetscCall(PetscStrcmpAny(bv->vtype,&standard,VECSEQ,VECMPI,""));
1368:   PetscCall(PetscStrcmpAny(bv->vtype,&cuda,VECSEQCUDA,VECMPICUDA,""));
1369:   if (standard || cuda) {
1370:     PetscCall(PetscStrcmpAny(bv->vtype,&mpi,VECMPI,VECMPICUDA,""));
1371:     PetscCall(PetscLayoutGetLocalSize(bv->map,&nloc));
1372:     PetscCall(PetscLayoutGetSize(bv->map,&N));
1373:     PetscCall(PetscLayoutGetBlockSize(bv->map,&bs));
1374:     if (cuda) {
1375: #if defined(PETSC_HAVE_CUDA)
1376:       if (mpi) PetscCall(VecCreateMPICUDAWithArray(PetscObjectComm((PetscObject)bv),bs,nloc,N,NULL,v));
1377:       else PetscCall(VecCreateSeqCUDAWithArray(PetscObjectComm((PetscObject)bv),bs,N,NULL,v));
1378: #endif
1379:     } else {
1380:       if (mpi) PetscCall(VecCreateMPIWithArray(PetscObjectComm((PetscObject)bv),bs,nloc,N,NULL,v));
1381:       else PetscCall(VecCreateSeqWithArray(PetscObjectComm((PetscObject)bv),bs,N,NULL,v));
1382:     }
1383:   } else PetscCall(BVCreateVec(bv,v)); /* standard duplicate, with internal array */
1384:   PetscFunctionReturn(PETSC_SUCCESS);
1385: }

1387: /*@C
1388:    BVSetVecType - Set the vector type to be used when creating vectors via BVCreateVec().

1390:    Collective

1392:    Input Parameters:
1393: +  bv - the basis vectors context
1394: -  vtype - the vector type

1396:    Level: advanced

1398:    Note:
1399:    This is not needed if the BV object is set up with BVSetSizesFromVec(), but may be
1400:    required in the case of BVSetSizes() if one wants to work with non-standard vectors.

1402: .seealso: BVGetVecType(), BVSetSizesFromVec(), BVSetSizes()
1403: @*/
1404: PetscErrorCode BVSetVecType(BV bv,VecType vtype)
1405: {
1406:   PetscBool   std;
1407:   PetscMPIInt size;

1409:   PetscFunctionBegin;
1411:   PetscCall(PetscFree(bv->vtype));
1412:   PetscCall(PetscStrcmp(vtype,VECSTANDARD,&std));
1413:   if (std) {
1414:     PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)bv),&size));
1415:     PetscCall(PetscStrallocpy((size==1)?VECSEQ:VECMPI,(char**)&bv->vtype));
1416:   } else PetscCall(PetscStrallocpy(vtype,(char**)&bv->vtype));
1417:   PetscFunctionReturn(PETSC_SUCCESS);
1418: }

1420: /*@C
1421:    BVGetVecType - Get the vector type to be used when creating vectors via BVCreateVec().

1423:    Not Collective

1425:    Input Parameter:
1426: .  bv - the basis vectors context

1428:    Output Parameter:
1429: .  vtype - the vector type

1431:    Level: advanced

1433: .seealso: BVSetVecType()
1434: @*/
1435: PetscErrorCode BVGetVecType(BV bv,VecType *vtype)
1436: {
1437:   PetscFunctionBegin;
1439:   PetscAssertPointer(vtype,2);
1440:   *vtype = bv->vtype;
1441:   PetscFunctionReturn(PETSC_SUCCESS);
1442: }

1444: /*@
1445:    BVCreateMat - Creates a new Mat object of dense type and copies the contents
1446:    of the BV object.

1448:    Collective

1450:    Input Parameter:
1451: .  bv - the basis vectors context

1453:    Output Parameter:
1454: .  A  - the new matrix

1456:    Notes:
1457:    The user is responsible of destroying the returned matrix.

1459:    The matrix contains all columns of the BV, not just the active columns.

1461:    Level: intermediate

1463: .seealso: BVCreateFromMat(), BVCreateVec(), BVGetMat()
1464: @*/
1465: PetscErrorCode BVCreateMat(BV bv,Mat *A)
1466: {
1467:   PetscInt ksave,lsave;
1468:   Mat      B;

1470:   PetscFunctionBegin;
1472:   BVCheckSizes(bv,1);
1473:   PetscAssertPointer(A,2);

1475:   PetscCall(MatCreateDenseFromVecType(PetscObjectComm((PetscObject)bv),bv->vtype,bv->n,PETSC_DECIDE,bv->N,bv->m,bv->ld,NULL,A));
1476:   lsave = bv->l;
1477:   ksave = bv->k;
1478:   bv->l = 0;
1479:   bv->k = bv->m;
1480:   PetscCall(BVGetMat(bv,&B));
1481:   PetscCall(MatCopy(B,*A,SAME_NONZERO_PATTERN));
1482:   PetscCall(BVRestoreMat(bv,&B));
1483:   bv->l = lsave;
1484:   bv->k = ksave;
1485:   PetscFunctionReturn(PETSC_SUCCESS);
1486: }

1488: PetscErrorCode BVGetMat_Default(BV bv,Mat *A)
1489: {
1490:   PetscScalar *vv,*aa;
1491:   PetscBool   create=PETSC_FALSE;
1492:   PetscInt    m,cols;

1494:   PetscFunctionBegin;
1495:   m = bv->k-bv->l;
1496:   if (!bv->Aget) create=PETSC_TRUE;
1497:   else {
1498:     PetscCall(MatDenseGetArray(bv->Aget,&aa));
1499:     PetscCheck(!aa,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"BVGetMat already called on this BV");
1500:     PetscCall(MatGetSize(bv->Aget,NULL,&cols));
1501:     if (cols!=m) {
1502:       PetscCall(MatDestroy(&bv->Aget));
1503:       create=PETSC_TRUE;
1504:     }
1505:   }
1506:   PetscCall(BVGetArray(bv,&vv));
1507:   if (create) {
1508:     PetscCall(MatCreateDenseFromVecType(PetscObjectComm((PetscObject)bv),bv->vtype,bv->n,PETSC_DECIDE,bv->N,m,bv->ld,vv,&bv->Aget)); /* pass a pointer to avoid allocation of storage */
1509:     PetscCall(MatDenseReplaceArray(bv->Aget,NULL));  /* replace with a null pointer, the value after BVRestoreMat */
1510:   }
1511:   PetscCall(MatDensePlaceArray(bv->Aget,vv+(bv->nc+bv->l)*bv->ld));  /* set the actual pointer */
1512:   *A = bv->Aget;
1513:   PetscFunctionReturn(PETSC_SUCCESS);
1514: }

1516: /*@
1517:    BVGetMat - Returns a Mat object of dense type that shares the memory of
1518:    the BV object.

1520:    Collective

1522:    Input Parameter:
1523: .  bv - the basis vectors context

1525:    Output Parameter:
1526: .  A  - the matrix

1528:    Notes:
1529:    The returned matrix contains only the active columns. If the content of
1530:    the Mat is modified, these changes are also done in the BV object. The
1531:    user must call BVRestoreMat() when no longer needed.

1533:    This operation implies a call to BVGetArray(), which may result in data
1534:    copies.

1536:    Level: advanced

1538: .seealso: BVRestoreMat(), BVCreateMat(), BVGetArray()
1539: @*/
1540: PetscErrorCode BVGetMat(BV bv,Mat *A)
1541: {
1542:   PetscFunctionBegin;
1544:   BVCheckSizes(bv,1);
1545:   PetscAssertPointer(A,2);
1546:   PetscUseTypeMethod(bv,getmat,A);
1547:   PetscFunctionReturn(PETSC_SUCCESS);
1548: }

1550: PetscErrorCode BVRestoreMat_Default(BV bv,Mat *A)
1551: {
1552:   PetscScalar *vv,*aa;

1554:   PetscFunctionBegin;
1555:   PetscCall(MatDenseGetArray(bv->Aget,&aa));
1556:   vv = aa-(bv->nc+bv->l)*bv->ld;
1557:   PetscCall(MatDenseResetArray(bv->Aget));
1558:   PetscCall(BVRestoreArray(bv,&vv));
1559:   *A = NULL;
1560:   PetscFunctionReturn(PETSC_SUCCESS);
1561: }

1563: /*@
1564:    BVRestoreMat - Restores the Mat obtained with BVGetMat().

1566:    Logically Collective

1568:    Input Parameters:
1569: +  bv - the basis vectors context
1570: -  A  - the fetched matrix

1572:    Note:
1573:    A call to this function must match a previous call of BVGetMat().
1574:    The effect is that the contents of the Mat are copied back to the
1575:    BV internal data structures.

1577:    Level: advanced

1579: .seealso: BVGetMat(), BVRestoreArray()
1580: @*/
1581: PetscErrorCode BVRestoreMat(BV bv,Mat *A)
1582: {
1583:   PetscFunctionBegin;
1585:   BVCheckSizes(bv,1);
1586:   PetscAssertPointer(A,2);
1587:   PetscCheck(bv->Aget,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"BVRestoreMat must match a previous call to BVGetMat");
1588:   PetscCheck(bv->Aget==*A,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Mat argument is not the same as the one obtained with BVGetMat");
1589:   PetscUseTypeMethod(bv,restoremat,A);
1590:   PetscFunctionReturn(PETSC_SUCCESS);
1591: }

1593: /*
1594:    Copy all user-provided attributes of V to another BV object W
1595:  */
1596: static inline PetscErrorCode BVDuplicate_Private(BV V,BV W)
1597: {
1598:   PetscFunctionBegin;
1599:   PetscCall(PetscLayoutReference(V->map,&W->map));
1600:   PetscCall(BVSetVecType(W,V->vtype));
1601:   W->ld           = V->ld;
1602:   PetscCall(BVSetType(W,((PetscObject)V)->type_name));
1603:   W->orthog_type  = V->orthog_type;
1604:   W->orthog_ref   = V->orthog_ref;
1605:   W->orthog_eta   = V->orthog_eta;
1606:   W->orthog_block = V->orthog_block;
1607:   if (V->matrix) PetscCall(PetscObjectReference((PetscObject)V->matrix));
1608:   W->matrix       = V->matrix;
1609:   W->indef        = V->indef;
1610:   W->vmm          = V->vmm;
1611:   W->rrandom      = V->rrandom;
1612:   W->deftol       = V->deftol;
1613:   if (V->rand) PetscCall(PetscObjectReference((PetscObject)V->rand));
1614:   W->rand         = V->rand;
1615:   W->sfocalled    = V->sfocalled;
1616:   PetscTryTypeMethod(V,duplicate,W);
1617:   PetscCall(PetscObjectStateIncrease((PetscObject)W));
1618:   PetscFunctionReturn(PETSC_SUCCESS);
1619: }

1621: /*@
1622:    BVDuplicate - Creates a new basis vector object of the same type and
1623:    dimensions as an existing one.

1625:    Collective

1627:    Input Parameter:
1628: .  V - basis vectors context

1630:    Output Parameter:
1631: .  W - location to put the new BV

1633:    Notes:
1634:    The new BV has the same type and dimensions as V. Also, the inner
1635:    product matrix and orthogonalization options are copied.

1637:    BVDuplicate() DOES NOT COPY the entries, but rather allocates storage
1638:    for the new basis vectors. Use BVCopy() to copy the contents.

1640:    Level: intermediate

1642: .seealso: BVDuplicateResize(), BVCreate(), BVSetSizesFromVec(), BVCopy()
1643: @*/
1644: PetscErrorCode BVDuplicate(BV V,BV *W)
1645: {
1646:   PetscFunctionBegin;
1649:   BVCheckSizes(V,1);
1650:   PetscAssertPointer(W,2);
1651:   PetscCall(BVCreate(PetscObjectComm((PetscObject)V),W));
1652:   (*W)->N = V->N;
1653:   (*W)->n = V->n;
1654:   (*W)->m = V->m;
1655:   (*W)->k = V->m;
1656:   PetscCall(BVDuplicate_Private(V,*W));
1657:   PetscFunctionReturn(PETSC_SUCCESS);
1658: }

1660: /*@
1661:    BVDuplicateResize - Creates a new basis vector object of the same type and
1662:    dimensions as an existing one, but with possibly different number of columns.

1664:    Collective

1666:    Input Parameters:
1667: +  V - basis vectors context
1668: -  m - the new number of columns

1670:    Output Parameter:
1671: .  W - location to put the new BV

1673:    Note:
1674:    This is equivalent of a call to BVDuplicate() followed by BVResize(). The
1675:    contents of V are not copied to W.

1677:    Level: intermediate

1679: .seealso: BVDuplicate(), BVResize()
1680: @*/
1681: PetscErrorCode BVDuplicateResize(BV V,PetscInt m,BV *W)
1682: {
1683:   PetscFunctionBegin;
1686:   BVCheckSizes(V,1);
1688:   PetscAssertPointer(W,3);
1689:   PetscCall(BVCreate(PetscObjectComm((PetscObject)V),W));
1690:   (*W)->N = V->N;
1691:   (*W)->n = V->n;
1692:   (*W)->m = m;
1693:   (*W)->k = m;
1694:   PetscCall(BVDuplicate_Private(V,*W));
1695:   PetscFunctionReturn(PETSC_SUCCESS);
1696: }

1698: /*@
1699:    BVGetCachedBV - Returns a BV object stored internally that holds the
1700:    result of B*X after a call to BVApplyMatrixBV().

1702:    Collective

1704:    Input Parameter:
1705: .  bv    - the basis vectors context

1707:    Output Parameter:
1708: .  cached - the cached BV

1710:    Note:
1711:    The cached BV is created if not available previously.

1713:    Level: developer

1715: .seealso: BVApplyMatrixBV()
1716: @*/
1717: PetscErrorCode BVGetCachedBV(BV bv,BV *cached)
1718: {
1719:   PetscFunctionBegin;
1721:   PetscAssertPointer(cached,2);
1722:   BVCheckSizes(bv,1);
1723:   if (!bv->cached) {
1724:     PetscCall(BVCreate(PetscObjectComm((PetscObject)bv),&bv->cached));
1725:     bv->cached->N = bv->N;
1726:     bv->cached->n = bv->n;
1727:     bv->cached->m = bv->m;
1728:     bv->cached->k = bv->m;
1729:     PetscCall(BVDuplicate_Private(bv,bv->cached));
1730:   }
1731:   *cached = bv->cached;
1732:   PetscFunctionReturn(PETSC_SUCCESS);
1733: }

1735: /*@
1736:    BVCopy - Copies a basis vector object into another one, W <- V.

1738:    Logically Collective

1740:    Input Parameter:
1741: .  V - basis vectors context

1743:    Output Parameter:
1744: .  W - the copy

1746:    Note:
1747:    Both V and W must be distributed in the same manner; local copies are
1748:    done. Only active columns (excluding the leading ones) are copied.
1749:    In the destination W, columns are overwritten starting from the leading ones.
1750:    Constraints are not copied.

1752:    Level: beginner

1754: .seealso: BVCopyVec(), BVCopyColumn(), BVDuplicate(), BVSetActiveColumns()
1755: @*/
1756: PetscErrorCode BVCopy(BV V,BV W)
1757: {
1758:   PetscScalar       *womega;
1759:   const PetscScalar *vomega;

1761:   PetscFunctionBegin;
1764:   BVCheckSizes(V,1);
1765:   BVCheckOp(V,1,copy);
1768:   BVCheckSizes(W,2);
1769:   PetscCheckSameTypeAndComm(V,1,W,2);
1770:   PetscCheck(V->n==W->n,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_INCOMP,"Mismatching local dimension V %" PetscInt_FMT ", W %" PetscInt_FMT,V->n,W->n);
1771:   PetscCheck(V->k-V->l<=W->m-W->l,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_SIZ,"W has %" PetscInt_FMT " non-leading columns, not enough to store %" PetscInt_FMT " columns",W->m-W->l,V->k-V->l);
1772:   if (V==W || !V->n) PetscFunctionReturn(PETSC_SUCCESS);

1774:   PetscCall(PetscLogEventBegin(BV_Copy,V,W,0,0));
1775:   if (V->indef && V->matrix && V->indef==W->indef && V->matrix==W->matrix) {
1776:     /* copy signature */
1777:     PetscCall(BV_AllocateSignature(W));
1778:     PetscCall(VecGetArrayRead(V->omega,&vomega));
1779:     PetscCall(VecGetArray(W->omega,&womega));
1780:     PetscCall(PetscArraycpy(womega+W->nc+W->l,vomega+V->nc+V->l,V->k-V->l));
1781:     PetscCall(VecRestoreArray(W->omega,&womega));
1782:     PetscCall(VecRestoreArrayRead(V->omega,&vomega));
1783:   }
1784:   PetscUseTypeMethod(V,copy,W);
1785:   PetscCall(PetscLogEventEnd(BV_Copy,V,W,0,0));
1786:   PetscCall(PetscObjectStateIncrease((PetscObject)W));
1787:   PetscFunctionReturn(PETSC_SUCCESS);
1788: }

1790: /*@
1791:    BVCopyVec - Copies one of the columns of a basis vectors object into a Vec.

1793:    Logically Collective

1795:    Input Parameters:
1796: +  V - basis vectors context
1797: -  j - the column number to be copied

1799:    Output Parameter:
1800: .  w - the copied column

1802:    Note:
1803:    Both V and w must be distributed in the same manner; local copies are done.

1805:    Level: beginner

1807: .seealso: BVCopy(), BVCopyColumn(), BVInsertVec()
1808: @*/
1809: PetscErrorCode BVCopyVec(BV V,PetscInt j,Vec w)
1810: {
1811:   PetscInt       n,N;
1812:   Vec            z;

1814:   PetscFunctionBegin;
1817:   BVCheckSizes(V,1);
1820:   PetscCheckSameComm(V,1,w,3);

1822:   PetscCall(VecGetSize(w,&N));
1823:   PetscCall(VecGetLocalSize(w,&n));
1824:   PetscCheck(N==V->N && n==V->n,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_INCOMP,"Vec sizes (global %" PetscInt_FMT ", local %" PetscInt_FMT ") do not match BV sizes (global %" PetscInt_FMT ", local %" PetscInt_FMT ")",N,n,V->N,V->n);

1826:   PetscCall(PetscLogEventBegin(BV_Copy,V,w,0,0));
1827:   PetscCall(BVGetColumn(V,j,&z));
1828:   PetscCall(VecCopy(z,w));
1829:   PetscCall(BVRestoreColumn(V,j,&z));
1830:   PetscCall(PetscLogEventEnd(BV_Copy,V,w,0,0));
1831:   PetscFunctionReturn(PETSC_SUCCESS);
1832: }

1834: /*@
1835:    BVCopyColumn - Copies the values from one of the columns to another one.

1837:    Logically Collective

1839:    Input Parameters:
1840: +  V - basis vectors context
1841: .  j - the number of the source column
1842: -  i - the number of the destination column

1844:    Level: beginner

1846: .seealso: BVCopy(), BVCopyVec()
1847: @*/
1848: PetscErrorCode BVCopyColumn(BV V,PetscInt j,PetscInt i)
1849: {
1850:   PetscScalar *omega;

1852:   PetscFunctionBegin;
1855:   BVCheckSizes(V,1);
1858:   if (j==i) PetscFunctionReturn(PETSC_SUCCESS);

1860:   PetscCall(PetscLogEventBegin(BV_Copy,V,0,0,0));
1861:   if (V->omega) {
1862:     PetscCall(VecGetArray(V->omega,&omega));
1863:     omega[i] = omega[j];
1864:     PetscCall(VecRestoreArray(V->omega,&omega));
1865:   }
1866:   PetscUseTypeMethod(V,copycolumn,j,i);
1867:   PetscCall(PetscLogEventEnd(BV_Copy,V,0,0,0));
1868:   PetscCall(PetscObjectStateIncrease((PetscObject)V));
1869:   PetscFunctionReturn(PETSC_SUCCESS);
1870: }

1872: static PetscErrorCode BVGetSplit_Private(BV bv,PetscBool left,BV *split)
1873: {
1874:   PetscInt  ncols;

1876:   PetscFunctionBegin;
1877:   ncols = left? bv->nc+bv->l: bv->m-bv->l;
1878:   if (*split && ncols!=(*split)->m) PetscCall(BVDestroy(split));
1879:   if (!*split) {
1880:     PetscCall(BVCreate(PetscObjectComm((PetscObject)bv),split));
1881:     (*split)->issplit = left? 1: 2;
1882:     (*split)->splitparent = bv;
1883:     (*split)->N = bv->N;
1884:     (*split)->n = bv->n;
1885:     (*split)->m = bv->m;
1886:     (*split)->k = bv->m;
1887:     PetscCall(BVDuplicate_Private(bv,*split));
1888:   }
1889:   (*split)->l  = 0;
1890:   (*split)->k  = left? bv->l: bv->k-bv->l;
1891:   (*split)->nc = left? bv->nc: 0;
1892:   (*split)->m  = ncols-(*split)->nc;
1893:   if ((*split)->nc) {
1894:     (*split)->ci[0] = -(*split)->nc-1;
1895:     (*split)->ci[1] = -(*split)->nc-1;
1896:   }
1897:   if (left) PetscCall(PetscObjectStateGet((PetscObject)*split,&bv->lstate));
1898:   else PetscCall(PetscObjectStateGet((PetscObject)*split,&bv->rstate));
1899:   PetscFunctionReturn(PETSC_SUCCESS);
1900: }

1902: /*@
1903:    BVGetSplit - Splits the BV object into two BV objects that share the
1904:    internal data, one of them containing the leading columns and the other
1905:    one containing the remaining columns.

1907:    Collective

1909:    Input Parameter:
1910: .  bv - the basis vectors context

1912:    Output Parameters:
1913: +  L - left BV containing leading columns (can be NULL)
1914: -  R - right BV containing remaining columns (can be NULL)

1916:    Notes:
1917:    The columns are split in two sets. The leading columns (including the
1918:    constraints) are assigned to the left BV and the remaining columns
1919:    are assigned to the right BV. The number of leading columns, as
1920:    specified with BVSetActiveColumns(), must be between 1 and m-1 (to
1921:    guarantee that both L and R have at least one column).

1923:    The returned BV's must be seen as references (not copies) of the input
1924:    BV, that is, modifying them will change the entries of bv as well.
1925:    The returned BV's must not be destroyed. BVRestoreSplit() must be called
1926:    when they are no longer needed.

1928:    Pass NULL for any of the output BV's that is not needed.

1930:    Level: advanced

1932: .seealso: BVRestoreSplit(), BVSetActiveColumns(), BVSetNumConstraints()
1933: @*/
1934: PetscErrorCode BVGetSplit(BV bv,BV *L,BV *R)
1935: {
1936:   PetscFunctionBegin;
1939:   BVCheckSizes(bv,1);
1940:   PetscCheck(bv->l,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Must indicate the number of leading columns with BVSetActiveColumns()");
1941:   PetscCheck(!bv->lsplit,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot get the split BV's twice before restoring them with BVRestoreSplit()");
1942:   bv->lsplit = bv->nc+bv->l;
1943:   PetscCall(BVGetSplit_Private(bv,PETSC_TRUE,&bv->L));
1944:   PetscCall(BVGetSplit_Private(bv,PETSC_FALSE,&bv->R));
1945:   if (L) *L = bv->L;
1946:   if (R) *R = bv->R;
1947:   PetscFunctionReturn(PETSC_SUCCESS);
1948: }

1950: /*@
1951:    BVRestoreSplit - Restore the BV objects obtained with BVGetSplit().

1953:    Logically Collective

1955:    Input Parameters:
1956: +  bv - the basis vectors context
1957: .  L  - left BV obtained with BVGetSplit()
1958: -  R  - right BV obtained with BVGetSplit()

1960:    Note:
1961:    The arguments must match the corresponding call to BVGetSplit().

1963:    Level: advanced

1965: .seealso: BVGetSplit()
1966: @*/
1967: PetscErrorCode BVRestoreSplit(BV bv,BV *L,BV *R)
1968: {
1969:   PetscFunctionBegin;
1972:   BVCheckSizes(bv,1);
1973:   PetscCheck(bv->lsplit,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Must call BVGetSplit first");
1974:   PetscCheck(!L || *L==bv->L,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Argument 2 is not the same BV that was obtained with BVGetSplit");
1975:   PetscCheck(!R || *R==bv->R,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Argument 3 is not the same BV that was obtained with BVGetSplit");
1976:   PetscCheck(!L || ((*L)->ci[0]<=(*L)->nc-1 && (*L)->ci[1]<=(*L)->nc-1),PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Argument 2 has unrestored columns, use BVRestoreColumn()");
1977:   PetscCheck(!R || ((*R)->ci[0]<=(*R)->nc-1 && (*R)->ci[1]<=(*R)->nc-1),PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Argument 3 has unrestored columns, use BVRestoreColumn()");

1979:   PetscTryTypeMethod(bv,restoresplit,L,R);
1980:   bv->lsplit = 0;
1981:   if (L) *L = NULL;
1982:   if (R) *R = NULL;
1983:   PetscFunctionReturn(PETSC_SUCCESS);
1984: }

1986: /*@
1987:    BVSetDefiniteTolerance - Set the tolerance to be used when checking a
1988:    definite inner product.

1990:    Logically Collective

1992:    Input Parameters:
1993: +  bv     - basis vectors
1994: -  deftol - the tolerance

1996:    Options Database Key:
1997: .  -bv_definite_tol <deftol> - the tolerance

1999:    Notes:
2000:    When using a non-standard inner product, see BVSetMatrix(), the solver needs
2001:    to compute sqrt(z'*B*z) for various vectors z. If the inner product has not
2002:    been declared indefinite, the value z'*B*z must be positive, but due to
2003:    rounding error a tiny value may become negative. A tolerance is used to
2004:    detect this situation. Likewise, in complex arithmetic z'*B*z should be
2005:    real, and we use the same tolerance to check whether a nonzero imaginary part
2006:    can be considered negligible.

2008:    This function sets this tolerance, which defaults to 10*eps, where eps is
2009:    the machine epsilon. The default value should be good for most applications.

2011:    Level: advanced

2013: .seealso: BVSetMatrix()
2014: @*/
2015: PetscErrorCode BVSetDefiniteTolerance(BV bv,PetscReal deftol)
2016: {
2017:   PetscFunctionBegin;
2020:   if (deftol == (PetscReal)PETSC_DEFAULT) bv->deftol = 10*PETSC_MACHINE_EPSILON;
2021:   else {
2022:     PetscCheck(deftol>0.0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of deftol. Must be > 0");
2023:     bv->deftol = deftol;
2024:   }
2025:   PetscFunctionReturn(PETSC_SUCCESS);
2026: }

2028: /*@
2029:    BVGetDefiniteTolerance - Returns the tolerance for checking a definite
2030:    inner product.

2032:    Not Collective

2034:    Input Parameter:
2035: .  bv - the basis vectors

2037:    Output Parameter:
2038: .  deftol - the tolerance

2040:    Level: advanced

2042: .seealso: BVSetDefiniteTolerance()
2043: @*/
2044: PetscErrorCode BVGetDefiniteTolerance(BV bv,PetscReal *deftol)
2045: {
2046:   PetscFunctionBegin;
2048:   PetscAssertPointer(deftol,2);
2049:   *deftol = bv->deftol;
2050:   PetscFunctionReturn(PETSC_SUCCESS);
2051: }

2053: /*@
2054:    BVSetLeadingDimension - Set the leading dimension to be used for storing the BV data.

2056:    Not Collective

2058:    Input Parameters:
2059: +  bv - basis vectors
2060: -  ld - the leading dimension

2062:    Notes:
2063:    This parameter is relevant for BVMAT, though it might be employed in other types
2064:    as well.

2066:    When the internal data of the BV is stored as a dense matrix, the leading dimension
2067:    has the same meaning as in MatDenseSetLDA(), i.e., the distance in number of
2068:    elements from one entry of the matrix to the one in the next column at the same
2069:    row. The leading dimension refers to the local array, and hence can be different
2070:    in different processes.

2072:    The user does not need to change this parameter. The default value is equal to the
2073:    number of local rows, but this value may be increased a little to guarantee alignment
2074:    (especially in the case of GPU storage).

2076:    Level: advanced

2078: .seealso: BVGetLeadingDimension()
2079: @*/
2080: PetscErrorCode BVSetLeadingDimension(BV bv,PetscInt ld)
2081: {
2082:   PetscFunctionBegin;
2085:   PetscCheck((bv->n<0 && bv->N<0) || !bv->ops->create,PetscObjectComm((PetscObject)bv),PETSC_ERR_ORDER,"Must call BVSetLeadingDimension() before setting the BV type and sizes");
2086:   if (ld == PETSC_DEFAULT) bv->ld = 0;
2087:   else {
2088:     PetscCheck(ld>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of ld. Must be > 0");
2089:     bv->ld = ld;
2090:   }
2091:   PetscFunctionReturn(PETSC_SUCCESS);
2092: }

2094: /*@
2095:    BVGetLeadingDimension - Returns the leading dimension of the BV.

2097:    Not Collective

2099:    Input Parameter:
2100: .  bv - the basis vectors

2102:    Output Parameter:
2103: .  ld - the leading dimension

2105:    Level: advanced

2107:    Notes:
2108:    The returned value may be different in different processes.

2110:    The leading dimension must be used when accessing the internal array via
2111:    BVGetArray() or BVGetArrayRead().

2113: .seealso: BVSetLeadingDimension(), BVGetArray(), BVGetArrayRead()
2114: @*/
2115: PetscErrorCode BVGetLeadingDimension(BV bv,PetscInt *ld)
2116: {
2117:   PetscFunctionBegin;
2119:   PetscAssertPointer(ld,2);
2120:   *ld = bv->ld;
2121:   PetscFunctionReturn(PETSC_SUCCESS);
2122: }