Actual source code: bvglobal.c

slepc-3.6.3 2016-03-29
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  1: /*
  2:    BV operations involving global communication.

  4:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  5:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  6:    Copyright (c) 2002-2015, Universitat Politecnica de Valencia, Spain

  8:    This file is part of SLEPc.

 10:    SLEPc is free software: you can redistribute it and/or modify it under  the
 11:    terms of version 3 of the GNU Lesser General Public License as published by
 12:    the Free Software Foundation.

 14:    SLEPc  is  distributed in the hope that it will be useful, but WITHOUT  ANY
 15:    WARRANTY;  without even the implied warranty of MERCHANTABILITY or  FITNESS
 16:    FOR  A  PARTICULAR PURPOSE. See the GNU Lesser General Public  License  for
 17:    more details.

 19:    You  should have received a copy of the GNU Lesser General  Public  License
 20:    along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
 21:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 22: */

 24: #include <slepc/private/bvimpl.h>      /*I "slepcbv.h" I*/

 28: /*
 29:   BVDot for the particular case of non-standard inner product with
 30:   matrix B, which is assumed to be symmetric (or complex Hermitian)
 31: */
 32: PETSC_STATIC_INLINE PetscErrorCode BVDot_Private(BV X,BV Y,Mat M)
 33: {
 35:   PetscObjectId  idx,idy;
 36:   PetscInt       i,j,jend,m;
 37:   PetscScalar    *marray;
 38:   PetscBool      symm=PETSC_FALSE;
 39:   Vec            z;

 42:   MatGetSize(M,&m,NULL);
 43:   MatDenseGetArray(M,&marray);
 44:   PetscObjectGetId((PetscObject)X,&idx);
 45:   PetscObjectGetId((PetscObject)Y,&idy);
 46:   if (idx==idy) symm=PETSC_TRUE;  /* M=X'BX is symmetric */
 47:   jend = X->k;
 48:   for (j=X->l;j<jend;j++) {
 49:     if (symm) Y->k = j+1;
 50:     BVGetColumn(X,j,&z);
 51:     (*Y->ops->dotvec)(Y,z,marray+j*m+Y->l);
 52:     BVRestoreColumn(X,j,&z);
 53:     if (symm) {
 54:       for (i=X->l;i<j;i++)
 55:         marray[j+i*m] = PetscConj(marray[i+j*m]);
 56:     }
 57:   }
 58:   MatDenseRestoreArray(M,&marray);
 59:   return(0);
 60: }

 64: /*@
 65:    BVDot - Computes the 'block-dot' product of two basis vectors objects.

 67:    Collective on BV

 69:    Input Parameters:
 70: +  X, Y - basis vectors
 71: -  M    - Mat object where the result must be placed

 73:    Output Parameter:
 74: .  M    - the resulting matrix

 76:    Notes:
 77:    This is the generalization of VecDot() for a collection of vectors, M = Y^H*X.
 78:    The result is a matrix M whose entry m_ij is equal to y_i^H x_j (where y_i^H
 79:    denotes the conjugate transpose of y_i).

 81:    If a non-standard inner product has been specified with BVSetMatrix(),
 82:    then the result is M = Y^H*B*X. In this case, both X and Y must have
 83:    the same associated matrix.

 85:    On entry, M must be a sequential dense Mat with dimensions m,n at least, where
 86:    m is the number of active columns of Y and n is the number of active columns of X.
 87:    Only rows (resp. columns) of M starting from ly (resp. lx) are computed,
 88:    where ly (resp. lx) is the number of leading columns of Y (resp. X).

 90:    X and Y need not be different objects.

 92:    Level: intermediate

 94: .seealso: BVDotVec(), BVDotColumn(), BVSetActiveColumns(), BVSetMatrix()
 95: @*/
 96: PetscErrorCode BVDot(BV X,BV Y,Mat M)
 97: {
 99:   PetscBool      match;
100:   PetscInt       m,n;

107:   BVCheckSizes(X,1);
109:   BVCheckSizes(Y,2);
112:   PetscObjectTypeCompare((PetscObject)M,MATSEQDENSE,&match);
113:   if (!match) SETERRQ(PetscObjectComm((PetscObject)X),PETSC_ERR_SUP,"Mat argument must be of type seqdense");

115:   MatGetSize(M,&m,&n);
116:   if (m<Y->k) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_SIZ,"Mat argument has %D rows, should have at least %D",m,Y->k);
117:   if (n<X->k) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_SIZ,"Mat argument has %D columns, should have at least %D",n,X->k);
118:   if (X->n!=Y->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Mismatching local dimension X %D, Y %D",X->n,Y->n);
119:   if (X->matrix!=Y->matrix) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"X and Y must have the same inner product matrix");
120:   if (X->l==X->k || Y->l==Y->k) return(0);

122:   PetscLogEventBegin(BV_Dot,X,Y,0,0);
123:   if (X->matrix) { /* non-standard inner product: cast into dotvec ops */
124:     BVDot_Private(X,Y,M);
125:   } else {
126:     (*X->ops->dot)(X,Y,M);
127:   }
128:   PetscLogEventEnd(BV_Dot,X,Y,0,0);
129:   return(0);
130: }

134: /*@
135:    BVDotVec - Computes multiple dot products of a vector against all the
136:    column vectors of a BV.

138:    Collective on BV and Vec

140:    Input Parameters:
141: +  X - basis vectors
142: -  y - a vector

144:    Output Parameter:
145: .  m - an array where the result must be placed

147:    Notes:
148:    This is analogue to VecMDot(), but using BV to represent a collection
149:    of vectors. The result is m = X^H*y, so m_i is equal to x_j^H y. Note
150:    that here X is transposed as opposed to BVDot().

152:    If a non-standard inner product has been specified with BVSetMatrix(),
153:    then the result is m = X^H*B*y.

155:    The length of array m must be equal to the number of active columns of X
156:    minus the number of leading columns, i.e. the first entry of m is the
157:    product of the first non-leading column with y.

159:    Level: intermediate

161: .seealso: BVDot(), BVDotColumn(), BVSetActiveColumns(), BVSetMatrix()
162: @*/
163: PetscErrorCode BVDotVec(BV X,Vec y,PetscScalar *m)
164: {
166:   PetscInt       n;

172:   BVCheckSizes(X,1);

176:   VecGetLocalSize(y,&n);
177:   if (X->n!=n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Mismatching local dimension X %D, y %D",X->n,n);

179:   PetscLogEventBegin(BV_Dot,X,y,0,0);
180:   (*X->ops->dotvec)(X,y,m);
181:   PetscLogEventEnd(BV_Dot,X,y,0,0);
182:   return(0);
183: }

187: /*@
188:    BVDotVecBegin - Starts a split phase dot product computation.

190:    Input Parameters:
191: +  X - basis vectors
192: .  y - a vector
193: -  m - an array where the result will go (can be NULL)

195:    Note:
196:    Each call to BVDotVecBegin() should be paired with a call to BVDotVecEnd().

198:    Level: advanced

200: .seealso: BVDotVecEnd(), BVDotVec()
201: @*/
202: PetscErrorCode BVDotVecBegin(BV X,Vec y,PetscScalar *m)
203: {
204:   PetscErrorCode      ierr;
205:   PetscInt            i,n,nv;
206:   PetscSplitReduction *sr;
207:   MPI_Comm            comm;

213:   BVCheckSizes(X,1);

217:   VecGetLocalSize(y,&n);
218:   if (X->n!=n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Mismatching local dimension X %D, y %D",X->n,n);

220:   if (X->ops->dotvec_begin) {
221:     (*X->ops->dotvec_begin)(X,y,m);
222:   } else {
223:     nv = X->k-X->l;
224:     PetscObjectGetComm((PetscObject)X,&comm);
225:     PetscSplitReductionGet(comm,&sr);
226:     if (sr->state != STATE_BEGIN) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ORDER,"Called before all VecxxxEnd() called");
227:     for (i=0;i<nv;i++) {
228:       if (sr->numopsbegin+i >= sr->maxops) {
229:         PetscSplitReductionExtend(sr);
230:       }
231:       sr->reducetype[sr->numopsbegin+i] = REDUCE_SUM;
232:       sr->invecs[sr->numopsbegin+i]     = (void*)X;
233:     }
234:     PetscLogEventBegin(BV_Dot,X,y,0,0);
235:     (*X->ops->dotvec_local)(X,y,sr->lvalues+sr->numopsbegin);
236:     sr->numopsbegin += nv;
237:     PetscLogEventEnd(BV_Dot,X,y,0,0);
238:   }
239:   return(0);
240: }

244: /*@
245:    BVDotVecEnd - Ends a split phase dot product computation.

247:    Input Parameters:
248: +  X - basis vectors
249: .  y - a vector
250: -  m - an array where the result will go

252:    Note:
253:    Each call to BVDotVecBegin() should be paired with a call to BVDotVecEnd().

255:    Level: advanced

257: .seealso: BVDotVecBegin(), BVDotVec()
258: @*/
259: PetscErrorCode BVDotVecEnd(BV X,Vec y,PetscScalar *m)
260: {
261:   PetscErrorCode      ierr;
262:   PetscInt            i,nv;
263:   PetscSplitReduction *sr;
264:   MPI_Comm            comm;

269:   BVCheckSizes(X,1);

271:   if (X->ops->dotvec_end) {
272:     (*X->ops->dotvec_end)(X,y,m);
273:   } else {
274:     nv = X->k-X->l;
275:     PetscObjectGetComm((PetscObject)X,&comm);
276:     PetscSplitReductionGet(comm,&sr);
277:     PetscSplitReductionEnd(sr);

279:     if (sr->numopsend >= sr->numopsbegin) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called VecxxxEnd() more times than VecxxxBegin()");
280:     if ((void*)X != sr->invecs[sr->numopsend]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called BVxxxEnd() in a different order or with a different BV than BVxxxBegin()");
281:     if (sr->reducetype[sr->numopsend] != REDUCE_SUM) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Wrong type of reduction");
282:     for (i=0;i<nv;i++) m[i] = sr->gvalues[sr->numopsend++];

284:     /* Finished getting all the results so reset to no outstanding requests */
285:     if (sr->numopsend == sr->numopsbegin) {
286:       sr->state       = STATE_BEGIN;
287:       sr->numopsend   = 0;
288:       sr->numopsbegin = 0;
289:     }
290:   }
291:   return(0);
292: }

296: /*@
297:    BVDotColumn - Computes multiple dot products of a column against all the
298:    previous columns of a BV.

300:    Collective on BV

302:    Input Parameters:
303: +  X - basis vectors
304: -  j - the column index

306:    Output Parameter:
307: .  m - an array where the result must be placed

309:    Notes:
310:    This operation is equivalent to BVDotVec() but it uses column j of X
311:    rather than taking a Vec as an argument. The number of active columns of
312:    X is set to j before the computation, and restored afterwards.
313:    If X has leading columns specified, then these columns do not participate
314:    in the computation. Therefore, the length of array m must be equal to j
315:    minus the number of leading columns.

317:    Level: advanced

319: .seealso: BVDot(), BVDotVec(), BVSetActiveColumns(), BVSetMatrix()
320: @*/
321: PetscErrorCode BVDotColumn(BV X,PetscInt j,PetscScalar *m)
322: {
324:   PetscInt       ksave;
325:   Vec            y;

331:   BVCheckSizes(X,1);

333:   if (j<0) SETERRQ(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_OUTOFRANGE,"Index j must be non-negative");
334:   if (j>=X->m) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_OUTOFRANGE,"Index j=%D but BV only has %D columns",j,X->m);

336:   PetscLogEventBegin(BV_Dot,X,0,0,0);
337:   ksave = X->k;
338:   X->k = j;
339:   BVGetColumn(X,j,&y);
340:   (*X->ops->dotvec)(X,y,m);
341:   BVRestoreColumn(X,j,&y);
342:   X->k = ksave;
343:   PetscLogEventEnd(BV_Dot,X,0,0,0);
344:   return(0);
345: }

349: /*@
350:    BVDotColumnBegin - Starts a split phase dot product computation.

352:    Input Parameters:
353: +  X - basis vectors
354: -  j - the column index
355: -  m - an array where the result will go (can be NULL)

357:    Note:
358:    Each call to BVDotColumnBegin() should be paired with a call to BVDotColumnEnd().

360:    Level: advanced

362: .seealso: BVDotColumnEnd(), BVDotColumn()
363: @*/
364: PetscErrorCode BVDotColumnBegin(BV X,PetscInt j,PetscScalar *m)
365: {
366:   PetscErrorCode      ierr;
367:   PetscInt            i,nv,ksave;
368:   PetscSplitReduction *sr;
369:   MPI_Comm            comm;
370:   Vec                 y;

376:   BVCheckSizes(X,1);

378:   if (j<0) SETERRQ(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_OUTOFRANGE,"Index j must be non-negative");
379:   if (j>=X->m) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_OUTOFRANGE,"Index j=%D but BV only has %D columns",j,X->m);
380:   ksave = X->k;
381:   X->k = j;
382:   BVGetColumn(X,j,&y);

384:   if (X->ops->dotvec_begin) {
385:     (*X->ops->dotvec_begin)(X,y,m);
386:   } else {
387:     nv = X->k-X->l;
388:     PetscObjectGetComm((PetscObject)X,&comm);
389:     PetscSplitReductionGet(comm,&sr);
390:     if (sr->state != STATE_BEGIN) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ORDER,"Called before all VecxxxEnd() called");
391:     for (i=0;i<nv;i++) {
392:       if (sr->numopsbegin+i >= sr->maxops) {
393:         PetscSplitReductionExtend(sr);
394:       }
395:       sr->reducetype[sr->numopsbegin+i] = REDUCE_SUM;
396:       sr->invecs[sr->numopsbegin+i]     = (void*)X;
397:     }
398:     PetscLogEventBegin(BV_Dot,X,0,0,0);
399:     (*X->ops->dotvec_local)(X,y,sr->lvalues+sr->numopsbegin);
400:     sr->numopsbegin += nv;
401:     PetscLogEventEnd(BV_Dot,X,0,0,0);
402:   }
403:   BVRestoreColumn(X,j,&y);
404:   X->k = ksave;
405:   return(0);
406: }

410: /*@
411:    BVDotColumnEnd - Ends a split phase dot product computation.

413:    Input Parameters:
414: +  X - basis vectors
415: -  j - the column index
416: -  m - an array where the result will go

418:    Note:
419:    Each call to BVDotColumnBegin() should be paired with a call to BVDotColumnEnd().

421:    Level: advanced

423: .seealso: BVDotColumnBegin(), BVDotColumn()
424: @*/
425: PetscErrorCode BVDotColumnEnd(BV X,PetscInt j,PetscScalar *m)
426: {
427:   PetscErrorCode      ierr;
428:   PetscInt            i,nv,ksave;
429:   PetscSplitReduction *sr;
430:   MPI_Comm            comm;
431:   Vec                 y;

437:   BVCheckSizes(X,1);

439:   if (j<0) SETERRQ(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_OUTOFRANGE,"Index j must be non-negative");
440:   if (j>=X->m) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_OUTOFRANGE,"Index j=%D but BV only has %D columns",j,X->m);
441:   ksave = X->k;
442:   X->k = j;

444:   if (X->ops->dotvec_end) {
445:     BVGetColumn(X,j,&y);
446:     (*X->ops->dotvec_end)(X,y,m);
447:     BVRestoreColumn(X,j,&y);
448:   } else {
449:     nv = X->k-X->l;
450:     PetscObjectGetComm((PetscObject)X,&comm);
451:     PetscSplitReductionGet(comm,&sr);
452:     PetscSplitReductionEnd(sr);

454:     if (sr->numopsend >= sr->numopsbegin) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called VecxxxEnd() more times than VecxxxBegin()");
455:     if ((void*)X != sr->invecs[sr->numopsend]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called BVxxxEnd() in a different order or with a different BV than BVxxxBegin()");
456:     if (sr->reducetype[sr->numopsend] != REDUCE_SUM) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Wrong type of reduction");
457:     for (i=0;i<nv;i++) m[i] = sr->gvalues[sr->numopsend++];

459:     /* Finished getting all the results so reset to no outstanding requests */
460:     if (sr->numopsend == sr->numopsbegin) {
461:       sr->state       = STATE_BEGIN;
462:       sr->numopsend   = 0;
463:       sr->numopsbegin = 0;
464:     }
465:   }
466:   X->k = ksave;
467:   return(0);
468: }

472: PETSC_STATIC_INLINE PetscErrorCode BVNorm_Private(BV bv,Vec z,NormType type,PetscReal *val)
473: {
475:   PetscScalar    p;

478:   BV_IPMatMult(bv,z);
479:   VecDot(bv->Bx,z,&p);
480:   BV_SafeSqrt(bv,p,val);
481:   return(0);
482: }

486: PETSC_STATIC_INLINE PetscErrorCode BVNorm_Begin_Private(BV bv,Vec z,NormType type,PetscReal *val)
487: {
489:   PetscScalar    p;

492:   BV_IPMatMult(bv,z);
493:   VecDotBegin(bv->Bx,z,&p);
494:   return(0);
495: }

499: PETSC_STATIC_INLINE PetscErrorCode BVNorm_End_Private(BV bv,Vec z,NormType type,PetscReal *val)
500: {
502:   PetscScalar    p;

505:   VecDotEnd(bv->Bx,z,&p);
506:   BV_SafeSqrt(bv,p,val);
507:   return(0);
508: }

512: /*@
513:    BVNorm - Computes the matrix norm of the BV.

515:    Collective on BV

517:    Input Parameters:
518: +  bv   - basis vectors
519: -  type - the norm type

521:    Output Parameter:
522: .  val  - the norm

524:    Notes:
525:    All active columns (except the leading ones) are considered as a matrix.
526:    The allowed norms are NORM_1, NORM_FROBENIUS, and NORM_INFINITY.

528:    This operation fails if a non-standard inner product has been
529:    specified with BVSetMatrix().

531:    Level: intermediate

533: .seealso: BVNormVec(), BVNormColumn(), BVSetActiveColumns(), BVSetMatrix()
534: @*/
535: PetscErrorCode BVNorm(BV bv,NormType type,PetscReal *val)
536: {

544:   BVCheckSizes(bv,1);

546:   if (type==NORM_2 || type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");
547:   if (bv->matrix) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Matrix norm not available for non-standard inner product");

549:   PetscLogEventBegin(BV_Norm,bv,0,0,0);
550:   (*bv->ops->norm)(bv,-1,type,val);
551:   PetscLogEventEnd(BV_Norm,bv,0,0,0);
552:   return(0);
553: }

557: /*@
558:    BVNormVec - Computes the norm of a given vector.

560:    Collective on BV

562:    Input Parameters:
563: +  bv   - basis vectors
564: .  v    - the vector
565: -  type - the norm type

567:    Output Parameter:
568: .  val  - the norm

570:    Notes:
571:    This is the analogue of BVNormColumn() but for a vector that is not in the BV.
572:    If a non-standard inner product has been specified with BVSetMatrix(),
573:    then the returned value is sqrt(v'*B*v), where B is the inner product
574:    matrix (argument 'type' is ignored). Otherwise, VecNorm() is called.

576:    Level: developer

578: .seealso: BVNorm(), BVNormColumn(), BVSetMatrix()
579: @*/
580: PetscErrorCode BVNormVec(BV bv,Vec v,NormType type,PetscReal *val)
581: {
583:   PetscInt       n;

591:   BVCheckSizes(bv,1);

595:   if (type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");

597:   PetscLogEventBegin(BV_Norm,bv,0,0,0);
598:   if (bv->matrix) { /* non-standard inner product */
599:     VecGetLocalSize(v,&n);
600:     if (bv->n!=n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Mismatching local dimension bv %D, v %D",bv->n,n);
601:     BVNorm_Private(bv,v,type,val);
602:   } else {
603:     VecNorm(v,type,val);
604:   }
605:   PetscLogEventEnd(BV_Norm,bv,0,0,0);
606:   return(0);
607: }

611: /*@
612:    BVNormVecBegin - Starts a split phase norm computation.

614:    Input Parameters:
615: +  bv   - basis vectors
616: .  v    - the vector
617: .  type - the norm type
618: -  val  - the norm

620:    Note:
621:    Each call to BVNormVecBegin() should be paired with a call to BVNormVecEnd().

623:    Level: advanced

625: .seealso: BVNormVecEnd(), BVNormVec()
626: @*/
627: PetscErrorCode BVNormVecBegin(BV bv,Vec v,NormType type,PetscReal *val)
628: {
630:   PetscInt       n;

638:   BVCheckSizes(bv,1);

642:   if (type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");

644:   PetscLogEventBegin(BV_Norm,bv,0,0,0);
645:   if (bv->matrix) { /* non-standard inner product */
646:     VecGetLocalSize(v,&n);
647:     if (bv->n!=n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Mismatching local dimension bv %D, v %D",bv->n,n);
648:     BVNorm_Begin_Private(bv,v,type,val);
649:   } else {
650:     VecNormBegin(v,type,val);
651:   }
652:   PetscLogEventEnd(BV_Norm,bv,0,0,0);
653:   return(0);
654: }

658: /*@
659:    BVNormVecEnd - Ends a split phase norm computation.

661:    Input Parameters:
662: +  bv   - basis vectors
663: .  v    - the vector
664: .  type - the norm type
665: -  val  - the norm

667:    Note:
668:    Each call to BVNormVecBegin() should be paired with a call to BVNormVecEnd().

670:    Level: advanced

672: .seealso: BVNormVecBegin(), BVNormVec()
673: @*/
674: PetscErrorCode BVNormVecEnd(BV bv,Vec v,NormType type,PetscReal *val)
675: {

683:   BVCheckSizes(bv,1);

685:   if (type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");

687:   if (bv->matrix) { /* non-standard inner product */
688:     BVNorm_End_Private(bv,v,type,val);
689:   } else {
690:     VecNormEnd(v,type,val);
691:   }
692:   return(0);
693: }

697: /*@
698:    BVNormColumn - Computes the vector norm of a selected column.

700:    Collective on BV

702:    Input Parameters:
703: +  bv   - basis vectors
704: .  j    - column number to be used
705: -  type - the norm type

707:    Output Parameter:
708: .  val  - the norm

710:    Notes:
711:    The norm of V[j] is computed (NORM_1, NORM_2, or NORM_INFINITY).
712:    If a non-standard inner product has been specified with BVSetMatrix(),
713:    then the returned value is sqrt(V[j]'*B*V[j]), 
714:    where B is the inner product matrix (argument 'type' is ignored).

716:    Level: intermediate

718: .seealso: BVNorm(), BVNormVec(), BVSetActiveColumns(), BVSetMatrix()
719: @*/
720: PetscErrorCode BVNormColumn(BV bv,PetscInt j,NormType type,PetscReal *val)
721: {
723:   Vec            z;

731:   BVCheckSizes(bv,1);

733:   if (j<0 || j>=bv->m) SETERRQ2(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Argument j has wrong value %D, the number of columns is %D",j,bv->m);
734:   if (type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");

736:   PetscLogEventBegin(BV_Norm,bv,0,0,0);
737:   if (bv->matrix) { /* non-standard inner product */
738:     BVGetColumn(bv,j,&z);
739:     BVNorm_Private(bv,z,type,val);
740:     BVRestoreColumn(bv,j,&z);
741:   } else {
742:     (*bv->ops->norm)(bv,j,type,val);
743:   }
744:   PetscLogEventEnd(BV_Norm,bv,0,0,0);
745:   return(0);
746: }

750: /*@
751:    BVNormColumnBegin - Starts a split phase norm computation.

753:    Input Parameters:
754: +  bv   - basis vectors
755: .  j    - column number to be used
756: .  type - the norm type
757: -  val  - the norm

759:    Note:
760:    Each call to BVNormColumnBegin() should be paired with a call to BVNormColumnEnd().

762:    Level: advanced

764: .seealso: BVNormColumnEnd(), BVNormColumn()
765: @*/
766: PetscErrorCode BVNormColumnBegin(BV bv,PetscInt j,NormType type,PetscReal *val)
767: {
768:   PetscErrorCode      ierr;
769:   PetscSplitReduction *sr;
770:   PetscReal           lresult;
771:   MPI_Comm            comm;
772:   Vec                 z;

780:   BVCheckSizes(bv,1);

782:   if (j<0 || j>=bv->m) SETERRQ2(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Argument j has wrong value %D, the number of columns is %D",j,bv->m);
783:   if (type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");

785:   PetscLogEventBegin(BV_Norm,bv,0,0,0);
786:   BVGetColumn(bv,j,&z);
787:   if (bv->matrix) { /* non-standard inner product */
788:     BVNorm_Begin_Private(bv,z,type,val);
789:   } else if (bv->ops->norm_begin) {
790:     (*bv->ops->norm_begin)(bv,j,type,val);
791:   } else {
792:     PetscObjectGetComm((PetscObject)z,&comm);
793:     PetscSplitReductionGet(comm,&sr);
794:     if (sr->state != STATE_BEGIN) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ORDER,"Called before all VecxxxEnd() called");
795:     if (sr->numopsbegin >= sr->maxops) {
796:       PetscSplitReductionExtend(sr);
797:     }
798:     sr->invecs[sr->numopsbegin] = (void*)bv;
799:     (*bv->ops->norm_local)(bv,j,type,&lresult);
800:     if (type == NORM_2) lresult = lresult*lresult;
801:     else if (type == NORM_MAX) sr->reducetype[sr->numopsbegin] = REDUCE_MAX;
802:     else sr->reducetype[sr->numopsbegin] = REDUCE_SUM;
803:     sr->lvalues[sr->numopsbegin++] = lresult;
804:   }
805:   BVRestoreColumn(bv,j,&z);
806:   PetscLogEventEnd(BV_Norm,bv,0,0,0);
807:   return(0);
808: }

812: /*@
813:    BVNormColumnEnd - Ends a split phase norm computation.

815:    Input Parameters:
816: +  bv   - basis vectors
817: .  j    - column number to be used
818: .  type - the norm type
819: -  val  - the norm

821:    Note:
822:    Each call to BVNormColumnBegin() should be paired with a call to BVNormColumnEnd().

824:    Level: advanced

826: .seealso: BVNormColumnBegin(), BVNormColumn()
827: @*/
828: PetscErrorCode BVNormColumnEnd(BV bv,PetscInt j,NormType type,PetscReal *val)
829: {
830:   PetscErrorCode      ierr;
831:   PetscSplitReduction *sr;
832:   MPI_Comm            comm;
833:   Vec                 z;

841:   BVCheckSizes(bv,1);

843:   if (type==NORM_1_AND_2) SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Requested norm not available");

845:   BVGetColumn(bv,j,&z);
846:   if (bv->matrix) { /* non-standard inner product */
847:     BVNorm_End_Private(bv,z,type,val);
848:   } else if (bv->ops->norm_end) {
849:     (*bv->ops->norm_end)(bv,j,type,val);
850:   } else {
851:     PetscObjectGetComm((PetscObject)z,&comm);
852:     PetscSplitReductionGet(comm,&sr);
853:     PetscSplitReductionEnd(sr);

855:     if (sr->numopsend >= sr->numopsbegin) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called VecxxxEnd() more times then VecxxxBegin()");
856:     if ((void*)bv != sr->invecs[sr->numopsend]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called VecxxxEnd() in a different order or with a different vector than VecxxxBegin()");
857:     if (sr->reducetype[sr->numopsend] != REDUCE_MAX && type == NORM_MAX) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Called BVNormEnd(,NORM_MAX,) on a reduction started with VecDotBegin() or NORM_1 or NORM_2");
858:     *val = PetscRealPart(sr->gvalues[sr->numopsend++]);
859:     if (type == NORM_2) *val = PetscSqrtReal(*val);
860:     if (sr->numopsend == sr->numopsbegin) {
861:       sr->state       = STATE_BEGIN;
862:       sr->numopsend   = 0;
863:       sr->numopsbegin = 0;
864:     }
865:   }
866:   BVRestoreColumn(bv,j,&z);
867:   return(0);
868: }

872: /*
873:   Compute Y^H*A*X: right part column by column (with MatMult) and bottom
874:   part row by row (with MatMultHermitianTranspose); result placed in marray[*,ldm]
875: */
876: PETSC_STATIC_INLINE PetscErrorCode BVMatProject_Vec(BV X,Mat A,BV Y,PetscScalar *marray,PetscInt ldm,PetscBool symm)
877: {
879:   PetscInt       i,j,lx,ly,kx,ky,ulim;
880:   Vec            z,f;

883:   lx = X->l; kx = X->k;
884:   ly = Y->l; ky = Y->k;
885:   BVCreateVec(X,&f);
886:   for (j=lx;j<kx;j++) {
887:     BVGetColumn(X,j,&z);
888:     MatMult(A,z,f);
889:     BVRestoreColumn(X,j,&z);
890:     ulim = PetscMin(ly+(j-lx)+1,ky);
891:     Y->l = 0; Y->k = ulim;
892:     (*Y->ops->dotvec)(Y,f,marray+j*ldm);
893:     if (symm) {
894:       for (i=0;i<j;i++) marray[j+i*ldm] = PetscConj(marray[i+j*ldm]);
895:     }
896:   }
897:   if (!symm) {
898:     BV_AllocateCoeffs(Y);
899:     for (j=ly;j<ky;j++) {
900:       BVGetColumn(Y,j,&z);
901:       MatMultHermitianTranspose(A,z,f);
902:       BVRestoreColumn(Y,j,&z);
903:       ulim = PetscMin(lx+(j-ly),kx);
904:       X->l = 0; X->k = ulim;
905:       (*X->ops->dotvec)(X,f,Y->h);
906:       for (i=0;i<ulim;i++) marray[j+i*ldm] = PetscConj(Y->h[i]);
907:     }
908:   }
909:   VecDestroy(&f);
910:   X->l = lx; X->k = kx;
911:   Y->l = ly; Y->k = ky;
912:   return(0);
913: }

917: /*
918:   Compute Y^H*A*X= [   --   | Y0'*W1 ]
919:                    [ Y1'*W0 | Y1'*W1 ]
920:   Allocates auxiliary BV to store the result of A*X, then one BVDot
921:   call for top-right part and another one for bottom part;
922:   result placed in marray[*,ldm]
923: */
924: PETSC_STATIC_INLINE PetscErrorCode BVMatProject_MatMult(BV X,Mat A,BV Y,PetscScalar *marray,PetscInt ldm)
925: {
927:   PetscInt       j,lx,ly,kx,ky;
928:   PetscScalar    *harray;
929:   Mat            H;
930:   BV             W;

933:   lx = X->l; kx = X->k;
934:   ly = Y->l; ky = Y->k;
935:   BVDuplicate(X,&W);
936:   X->l = 0; X->k = kx;
937:   BVMatMult(X,A,W);

939:   /* top-right part, Y0'*AX1 */
940:   if (ly>0 && lx<kx) {
941:     MatCreateSeqDense(PETSC_COMM_SELF,ly,kx,NULL,&H);
942:     W->l = lx; W->k = kx;
943:     Y->l = 0;  Y->k = ly;
944:     BVDot(W,Y,H);
945:     MatDenseGetArray(H,&harray);
946:     for (j=lx;j<kx;j++) {
947:       PetscMemcpy(marray+j*ldm,harray+j*ly,ly*sizeof(PetscScalar));
948:     }
949:     MatDenseRestoreArray(H,&harray);
950:     MatDestroy(&H);
951:   }

953:   /* bottom part, Y1'*AX */
954:   if (kx>0 && ly<ky) {
955:     MatCreateSeqDense(PETSC_COMM_SELF,ky,kx,NULL,&H);
956:     W->l = 0;  W->k = kx;
957:     Y->l = ly; Y->k = ky;
958:     BVDot(W,Y,H);
959:     MatDenseGetArray(H,&harray);
960:     for (j=0;j<kx;j++) {
961:       PetscMemcpy(marray+j*ldm+ly,harray+j*ky+ly,(ky-ly)*sizeof(PetscScalar));
962:     }
963:     MatDenseRestoreArray(H,&harray);
964:     MatDestroy(&H);
965:   }
966:   BVDestroy(&W);
967:   X->l = lx; X->k = kx;
968:   Y->l = ly; Y->k = ky;
969:   return(0);
970: }

974: /*
975:   Compute Y^H*A*X= [   --   | Y0'*W1 ]
976:                    [ Y1'*W0 | Y1'*W1 ]
977:   First stage: allocate auxiliary BV to store A*X1, one BVDot for right part;
978:   Second stage: resize BV to accomodate A'*Y1, then call BVDot for transpose of
979:   bottom-left part; result placed in marray[*,ldm]
980: */
981: PETSC_STATIC_INLINE PetscErrorCode BVMatProject_MatMult_2(BV X,Mat A,BV Y,PetscScalar *marray,PetscInt ldm,PetscBool symm)
982: {
984:   PetscInt       i,j,lx,ly,kx,ky;
985:   PetscScalar    *harray;
986:   Mat            H;
987:   BV             W;

990:   lx = X->l; kx = X->k;
991:   ly = Y->l; ky = Y->k;

993:   /* right part, Y'*AX1 */
994:   BVDuplicateResize(X,kx-lx,&W);
995:   if (ky>0 && lx<kx) {
996:     BVMatMult(X,A,W);
997:     MatCreateSeqDense(PETSC_COMM_SELF,ky,kx-lx,NULL,&H);
998:     Y->l = 0; Y->k = ky;
999:     BVDot(W,Y,H);
1000:     MatDenseGetArray(H,&harray);
1001:     for (j=lx;j<kx;j++) {
1002:       PetscMemcpy(marray+j*ldm,harray+(j-lx)*ky,ky*sizeof(PetscScalar));
1003:     }
1004:     MatDenseRestoreArray(H,&harray);
1005:     MatDestroy(&H);
1006:   }

1008:   /* bottom-left part, Y1'*AX0 */
1009:   if (lx>0 && ly<ky) {
1010:     if (symm) {
1011:       /* do not compute, just copy symmetric elements */
1012:       for (i=ly;i<ky;i++) {
1013:         for (j=0;j<lx;j++) marray[i+j*ldm] = PetscConj(marray[j+i*ldm]);
1014:       }
1015:     } else {
1016:       BVResize(W,ky-ly,PETSC_FALSE);
1017:       Y->l = ly; Y->k = ky;
1018:       BVMatMultHermitianTranspose(Y,A,W);
1019:       MatCreateSeqDense(PETSC_COMM_SELF,lx,ky-ly,NULL,&H);
1020:       X->l = 0; X->k = lx;
1021:       BVDot(W,X,H);
1022:       MatDenseGetArray(H,&harray);
1023:       for (i=0;i<ky-ly;i++) {
1024:         for (j=0;j<lx;j++) {
1025:           marray[i+j*ldm+ly] = PetscConj(harray[j+i*(ky-ly)]);
1026:         }
1027:       }
1028:       MatDenseRestoreArray(H,&harray);
1029:       MatDestroy(&H);
1030:     }
1031:   }
1032:   BVDestroy(&W);
1033:   X->l = lx; X->k = kx;
1034:   Y->l = ly; Y->k = ky;
1035:   return(0);
1036: }

1040: /*
1041:   Compute Y^H*X = [   --   | Y0'*X1 ]     (X contains A*X):
1042:                   [ Y1'*X0 | Y1'*X1 ]
1043:   one BVDot call for top-right part and another one for bottom part;
1044:   result placed in marray[*,ldm]
1045: */
1046: PETSC_STATIC_INLINE PetscErrorCode BVMatProject_Dot(BV X,BV Y,PetscScalar *marray,PetscInt ldm)
1047: {
1049:   PetscInt       j,lx,ly,kx,ky;
1050:   PetscScalar    *harray;
1051:   Mat            H;

1054:   lx = X->l; kx = X->k;
1055:   ly = Y->l; ky = Y->k;

1057:   /* top-right part, Y0'*X1 */
1058:   if (ly>0 && lx<kx) {
1059:     MatCreateSeqDense(PETSC_COMM_SELF,ly,kx,NULL,&H);
1060:     X->l = lx; X->k = kx;
1061:     Y->l = 0;  Y->k = ly;
1062:     BVDot(X,Y,H);
1063:     MatDenseGetArray(H,&harray);
1064:     for (j=lx;j<kx;j++) {
1065:       PetscMemcpy(marray+j*ldm,harray+j*ly,ly*sizeof(PetscScalar));
1066:     }
1067:     MatDenseRestoreArray(H,&harray);
1068:     MatDestroy(&H);
1069:   }

1071:   /* bottom part, Y1'*X */
1072:   if (kx>0 && ly<ky) {
1073:     MatCreateSeqDense(PETSC_COMM_SELF,ky,kx,NULL,&H);
1074:     X->l = 0;  X->k = kx;
1075:     Y->l = ly; Y->k = ky;
1076:     BVDot(X,Y,H);
1077:     MatDenseGetArray(H,&harray);
1078:     for (j=0;j<kx;j++) {
1079:       PetscMemcpy(marray+j*ldm+ly,harray+j*ky+ly,(ky-ly)*sizeof(PetscScalar));
1080:     }
1081:     MatDenseRestoreArray(H,&harray);
1082:     MatDestroy(&H);
1083:   }
1084:   X->l = lx; X->k = kx;
1085:   Y->l = ly; Y->k = ky;
1086:   return(0);
1087: }

1091: /*@
1092:    BVMatProject - Computes the projection of a matrix onto a subspace.

1094:    Collective on BV

1096:    Input Parameters:
1097: +  X - basis vectors
1098: .  A - (optional) matrix to be projected
1099: .  Y - left basis vectors, can be equal to X
1100: -  M - Mat object where the result must be placed

1102:    Output Parameter:
1103: .  M - the resulting matrix

1105:    Notes:
1106:    If A=NULL, then it is assumed that X already contains A*X.

1108:    This operation is similar to BVDot(), with important differences.
1109:    The goal is to compute the matrix resulting from the orthogonal projection
1110:    of A onto the subspace spanned by the columns of X, M = X^H*A*X, or the
1111:    oblique projection onto X along Y, M = Y^H*A*X.

1113:    A difference with respect to BVDot() is that the standard inner product
1114:    is always used, regardless of a non-standard inner product being specified
1115:    with BVSetMatrix().

1117:    On entry, M must be a sequential dense Mat with dimensions ky,kx at least,
1118:    where ky (resp. kx) is the number of active columns of Y (resp. X).
1119:    Another difference with respect to BVDot() is that all entries of M are
1120:    computed except the leading ly,lx part, where ly (resp. lx) is the
1121:    number of leading columns of Y (resp. X). Hence, the leading columns of
1122:    X and Y participate in the computation, as opposed to BVDot().
1123:    The leading part of M is assumed to be already available from previous
1124:    computations.

1126:    In the orthogonal projection case, Y=X, some computation can be saved if
1127:    A is real symmetric (or complex Hermitian). In order to exploit this
1128:    property, the symmetry flag of A must be set with MatSetOption().

1130:    Level: intermediate

1132: .seealso: BVDot(), BVSetActiveColumns(), BVSetMatrix()
1133: @*/
1134: PetscErrorCode BVMatProject(BV X,Mat A,BV Y,Mat M)
1135: {
1137:   PetscBool      match,set,flg,symm=PETSC_FALSE;
1138:   PetscInt       m,n;
1139:   PetscScalar    *marray;
1140:   Mat            Xmatrix,Ymatrix;
1141:   PetscObjectId  idx,idy;

1149:   BVCheckSizes(X,1);
1150:   if (A) {
1153:   }
1155:   BVCheckSizes(Y,3);
1158:   PetscObjectTypeCompare((PetscObject)M,MATSEQDENSE,&match);
1159:   if (!match) SETERRQ(PetscObjectComm((PetscObject)X),PETSC_ERR_SUP,"Matrix M must be of type seqdense");

1161:   MatGetSize(M,&m,&n);
1162:   if (m<Y->k) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_SIZ,"Matrix M has %D rows, should have at least %D",m,Y->k);
1163:   if (n<X->k) SETERRQ2(PetscObjectComm((PetscObject)X),PETSC_ERR_ARG_SIZ,"Matrix M has %D columns, should have at least %D",n,X->k);
1164:   if (X->n!=Y->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Mismatching local dimension X %D, Y %D",X->n,Y->n);

1166:   PetscLogEventBegin(BV_MatProject,X,A,Y,0);
1167:   /* temporarily set standard inner product */
1168:   Xmatrix = X->matrix;
1169:   Ymatrix = Y->matrix;
1170:   X->matrix = Y->matrix = NULL;

1172:   PetscObjectGetId((PetscObject)X,&idx);
1173:   PetscObjectGetId((PetscObject)Y,&idy);
1174:   if (!A && idx==idy) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Cannot set X=Y if A=NULL");

1176:   MatDenseGetArray(M,&marray);

1178:   if (A && idx==idy) { /* check symmetry of M=X'AX */
1179:     MatIsHermitianKnown(A,&set,&flg);
1180:     symm = set? flg: PETSC_FALSE;
1181:   }

1183:   if (A) { 
1184:     if (X->vmm==BV_MATMULT_VECS) {
1185:       /* perform computation column by column */
1186:       BVMatProject_Vec(X,A,Y,marray,m,symm);
1187:     } else {
1188:       /* use BVMatMult, then BVDot */
1189:       MatHasOperation(A,MATOP_MULT_TRANSPOSE,&flg);
1190:       if (symm || (flg && X->l>=X->k/2 && Y->l>=Y->k/2)) {
1191:         BVMatProject_MatMult_2(X,A,Y,marray,m,symm);
1192:       } else {
1193:         BVMatProject_MatMult(X,A,Y,marray,m);
1194:       }
1195:     }
1196:   } else {
1197:     /* use BVDot on subblocks */
1198:     BVMatProject_Dot(X,Y,marray,m);
1199:   }

1201:   MatDenseRestoreArray(M,&marray);
1202:   PetscLogEventEnd(BV_MatProject,X,A,Y,0);
1203:   /* restore non-standard inner product */
1204:   X->matrix = Xmatrix;
1205:   Y->matrix = Ymatrix;
1206:   return(0);
1207: }