Actual source code: svdopts.c

  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:    SVD routines for setting solver options
 12: */

 14: #include <slepc/private/svdimpl.h>
 15: #include <petscdraw.h>

 17: /*@
 18:    SVDSetImplicitTranspose - Indicates how to handle the transpose of the matrix
 19:    associated with the singular value problem.

 21:    Logically Collective

 23:    Input Parameters:
 24: +  svd  - the singular value solver context
 25: -  impl - how to handle the transpose (implicitly or not)

 27:    Options Database Key:
 28: .  -svd_implicittranspose - enable the implicit transpose mode

 30:    Notes:
 31:    By default, the transpose of the matrix is explicitly built (if the matrix
 32:    has defined the `MatTranspose()` operation, `MATOP_TRANSPOSE`).

 34:    If this flag is set to `PETSC_TRUE`, the solver does not build the transpose, but
 35:    handles it implicitly via `MatMultTranspose()` (or `MatMultHermitianTranspose()`
 36:    in the complex case) operations. This is likely to be more inefficient
 37:    than the default behavior, both sequentially and in parallel, but
 38:    requires less storage.

 40:    Level: advanced

 42: .seealso: [](ch:svd), `SVDGetImplicitTranspose()`, `SVDSolve()`, `SVDSetOperators()`
 43: @*/
 44: PetscErrorCode SVDSetImplicitTranspose(SVD svd,PetscBool impl)
 45: {
 46:   PetscFunctionBegin;
 49:   if (svd->impltrans!=impl) {
 50:     svd->impltrans = impl;
 51:     svd->state     = SVD_STATE_INITIAL;
 52:   }
 53:   PetscFunctionReturn(PETSC_SUCCESS);
 54: }

 56: /*@
 57:    SVDGetImplicitTranspose - Gets the mode used to handle the transpose
 58:    of the matrix associated with the singular value problem.

 60:    Not Collective

 62:    Input Parameter:
 63: .  svd  - the singular value solver context

 65:    Output Parameter:
 66: .  impl - how to handle the transpose (implicitly or not)

 68:    Level: advanced

 70: .seealso: [](ch:svd), `SVDSetImplicitTranspose()`, `SVDSolve()`, `SVDSetOperators()`
 71: @*/
 72: PetscErrorCode SVDGetImplicitTranspose(SVD svd,PetscBool *impl)
 73: {
 74:   PetscFunctionBegin;
 76:   PetscAssertPointer(impl,2);
 77:   *impl = svd->impltrans;
 78:   PetscFunctionReturn(PETSC_SUCCESS);
 79: }

 81: /*@
 82:    SVDSetTolerances - Sets the tolerance and maximum iteration count used
 83:    by the `SVD` convergence tests.

 85:    Logically Collective

 87:    Input Parameters:
 88: +  svd - the singular value solver context
 89: .  tol - the convergence tolerance
 90: -  maxits - maximum number of iterations to use

 92:    Options Database Keys:
 93: +  -svd_tol \<tol\>       - sets the convergence tolerance
 94: -  -svd_max_it \<maxits\> - sets the maximum number of iterations allowed

 96:    Note:
 97:    Use `PETSC_CURRENT` to retain the current value of any of the parameters.
 98:    Use `PETSC_DETERMINE` for either argument to assign a default value computed
 99:    internally (may be different in each solver).
100:    For `maxits` use `PETSC_UNLIMITED` to indicate there is no upper bound on this value.

102:    Level: intermediate

104: .seealso: [](ch:svd), `SVDGetTolerances()`
105: @*/
106: PetscErrorCode SVDSetTolerances(SVD svd,PetscReal tol,PetscInt maxits)
107: {
108:   PetscFunctionBegin;
112:   if (tol == (PetscReal)PETSC_DETERMINE) {
113:     svd->tol   = PETSC_DETERMINE;
114:     svd->state = SVD_STATE_INITIAL;
115:   } else if (tol != (PetscReal)PETSC_CURRENT) {
116:     PetscCheck(tol>0.0,PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of tol. Must be > 0");
117:     svd->tol = tol;
118:   }
119:   if (maxits == PETSC_DETERMINE) {
120:     svd->max_it = PETSC_DETERMINE;
121:     svd->state  = SVD_STATE_INITIAL;
122:   } else if (maxits == PETSC_UNLIMITED) {
123:     svd->max_it = PETSC_INT_MAX;
124:   } else if (maxits != PETSC_CURRENT) {
125:     PetscCheck(maxits>0,PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of maxits. Must be > 0");
126:     svd->max_it = maxits;
127:   }
128:   PetscFunctionReturn(PETSC_SUCCESS);
129: }

131: /*@
132:    SVDGetTolerances - Gets the tolerance and maximum
133:    iteration count used by the default SVD convergence tests.

135:    Not Collective

137:    Input Parameter:
138: .  svd - the singular value solver context

140:    Output Parameters:
141: +  tol - the convergence tolerance
142: -  maxits - maximum number of iterations

144:    Notes:
145:    The user can specify `NULL` for any parameter that is not needed.

147:    Level: intermediate

149: .seealso: [](ch:svd), `SVDSetTolerances()`
150: @*/
151: PetscErrorCode SVDGetTolerances(SVD svd,PetscReal *tol,PetscInt *maxits)
152: {
153:   PetscFunctionBegin;
155:   if (tol)    *tol    = svd->tol;
156:   if (maxits) *maxits = svd->max_it;
157:   PetscFunctionReturn(PETSC_SUCCESS);
158: }

160: /*@
161:    SVDSetThreshold - Sets the threshold used in the threshold stopping test.

163:    Logically Collective

165:    Input Parameters:
166: +  svd   - the singular value solver context
167: .  thres - the threshold value
168: -  rel   - whether the threshold is relative or not

170:    Options Database Keys:
171: +  -svd_threshold_absolute \<thres\> - sets an absolute threshold
172: -  -svd_threshold_relative \<thres\> - sets a relative threshold

174:    Notes:
175:    This function internally calls `SVDSetStoppingTest()` to set a special stopping
176:    test based on the threshold, where singular values are computed in sequence
177:    until one of the computed singular values is below the threshold `thres`.

179:    If the solver is configured to compute smallest singular values, then the
180:    threshold must be interpreted in the opposite direction, i.e., the computation
181:    will stop when one of the computed singular values is above the threshold.

183:    In the case of largest singular values, the threshold can be made relative
184:    with respect to the largest singular value (i.e., the matrix norm). Otherwise,
185:    the argument `rel` should be `PETSC_FALSE`.

187:    The test against the threshold is done for converged singular values, which
188:    implies that the final number of converged singular values will be at least
189:    one more than the actual number of values below/above the threshold.

191:    Since the number of computed singular values is not known a priori, the solver
192:    will need to reallocate the basis of vectors internally, to have enough room
193:    to accommodate all the singular vectors. Hence, this option must be used with
194:    caution to avoid out-of-memory problems. The recommendation is to set the value
195:    of `ncv` to be larger than the estimated number of singular values, to minimize
196:    the number of reallocations.

198:    This functionality is most useful when computing largest singular values. A
199:    typical use case is to compute a low rank approximation of a matrix. Suppose
200:    we know that singular values decay abruptly around a certain index $k$, which
201:    is unknown. Then using a small relative threshold such as 0.2 will guarantee that
202:    the computed singular vectors capture the numerical rank $k$. However, if the matrix
203:    does not have low rank, i.e., singular values decay progressively, then a
204:    value of 0.2 will imply a very high cost, both computationally and in memory.

206:    If a number of wanted singular values has been set with `SVDSetDimensions()`
207:    it is also taken into account and the solver will stop when one of the two
208:    conditions (threshold or number of converged values) is met.

210:    Use `SVDSetStoppingTest()` to return to the usual computation of a fixed number
211:    of singular values.

213:    Level: advanced

215: .seealso: [](ch:svd), `SVDGetThreshold()`, `SVDSetStoppingTest()`, `SVDSetDimensions()`, `SVDSetWhichSingularTriplets()`
216: @*/
217: PetscErrorCode SVDSetThreshold(SVD svd,PetscReal thres,PetscBool rel)
218: {
219:   PetscFunctionBegin;
223:   PetscCheck(thres>0.0,PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of the threshold. Must be > 0");
224:   if (svd->thres != thres || svd->threlative != rel) {
225:     svd->thres = thres;
226:     svd->threlative = rel;
227:     svd->state = SVD_STATE_INITIAL;
228:     PetscCall(SVDSetStoppingTest(svd,SVD_STOP_THRESHOLD));
229:   }
230:   PetscFunctionReturn(PETSC_SUCCESS);
231: }

233: /*@
234:    SVDGetThreshold - Gets the threshold used by the threshold stopping test.

236:    Not Collective

238:    Input Parameter:
239: .  svd - the singular value solver context

241:    Output Parameters:
242: +  thres - the threshold
243: -  rel   - whether the threshold is relative or not

245:    Level: advanced

247: .seealso: [](ch:svd), `SVDSetThreshold()`
248: @*/
249: PetscErrorCode SVDGetThreshold(SVD svd,PetscReal *thres,PetscBool *rel)
250: {
251:   PetscFunctionBegin;
253:   if (thres) *thres = svd->thres;
254:   if (rel)   *rel   = svd->threlative;
255:   PetscFunctionReturn(PETSC_SUCCESS);
256: }

258: /*@
259:    SVDSetDimensions - Sets the number of singular values to compute
260:    and the dimension of the subspace.

262:    Logically Collective

264:    Input Parameters:
265: +  svd - the singular value solver context
266: .  nsv - number of singular values to compute
267: .  ncv - the maximum dimension of the subspace to be used by the solver
268: -  mpd - the maximum dimension allowed for the projected problem

270:    Options Database Keys:
271: +  -svd_nsv \<nsv\> - sets the number of singular values
272: .  -svd_ncv \<ncv\> - sets the dimension of the subspace
273: -  -svd_mpd \<mpd\> - sets the maximum projected dimension

275:    Notes:
276:    Use `PETSC_DETERMINE` for `ncv` and `mpd` to assign a reasonably good value, which is
277:    dependent on the solution method and the number of singular values required. For
278:    any of the arguments, use `PETSC_CURRENT` to preserve the current value.

280:    The parameters `ncv` and `mpd` are intimately related, so that the user is advised
281:    to set one of them at most. Normal usage is\:

283:     1. In cases where `nsv` is small, the user sets `ncv` (a reasonable default is `2*nsv`).
284:     1. In cases where `nsv` is large, the user sets `mpd`.

286:    The value of `ncv` should always be between `nsv` and `(nsv+mpd)`, typically
287:    `ncv=nsv+mpd`. If `nsv` is not too large, `mpd=nsv` is a reasonable choice, otherwise
288:    a smaller value should be used.

290:    Level: intermediate

292: .seealso: [](ch:svd), `SVDGetDimensions()`
293: @*/
294: PetscErrorCode SVDSetDimensions(SVD svd,PetscInt nsv,PetscInt ncv,PetscInt mpd)
295: {
296:   PetscFunctionBegin;
301:   if (nsv != PETSC_CURRENT) {
302:     PetscCheck(nsv>0,PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of nsv. Must be > 0");
303:     svd->nsv = nsv;
304:   }
305:   if (ncv == PETSC_DETERMINE) {
306:     svd->ncv = PETSC_DETERMINE;
307:   } else if (ncv != PETSC_CURRENT) {
308:     PetscCheck(ncv>0,PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of ncv. Must be > 0");
309:     svd->ncv = ncv;
310:   }
311:   if (mpd == PETSC_DETERMINE) {
312:     svd->mpd = PETSC_DETERMINE;
313:   } else if (mpd != PETSC_CURRENT) {
314:     PetscCheck(mpd>0,PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of mpd. Must be > 0");
315:     svd->mpd = mpd;
316:   }
317:   svd->state = SVD_STATE_INITIAL;
318:   PetscFunctionReturn(PETSC_SUCCESS);
319: }

321: /*@
322:    SVDGetDimensions - Gets the number of singular values to compute
323:    and the dimension of the subspace.

325:    Not Collective

327:    Input Parameter:
328: .  svd - the singular value solver context

330:    Output Parameters:
331: +  nsv - number of singular values to compute
332: .  ncv - the maximum dimension of the subspace to be used by the solver
333: -  mpd - the maximum dimension allowed for the projected problem

335:    Notes:
336:    The user can specify `NULL` for any parameter that is not needed.

338:    Level: intermediate

340: .seealso: [](ch:svd), `SVDSetDimensions()`
341: @*/
342: PetscErrorCode SVDGetDimensions(SVD svd,PetscInt *nsv,PetscInt *ncv,PetscInt *mpd)
343: {
344:   PetscFunctionBegin;
346:   if (nsv) *nsv = svd->nsv? svd->nsv: 1;
347:   if (ncv) *ncv = svd->ncv;
348:   if (mpd) *mpd = svd->mpd;
349:   PetscFunctionReturn(PETSC_SUCCESS);
350: }

352: /*@
353:     SVDSetWhichSingularTriplets - Specifies which singular triplets are
354:     to be sought.

356:     Logically Collective

358:     Input Parameter:
359: .   svd - the singular value solver context

361:     Output Parameter:
362: .   which - which singular triplets are to be sought, see `SVDWhich` for possible values

364:     Options Database Keys:
365: +   -svd_largest  - sets largest singular values
366: -   -svd_smallest - sets smallest singular values

368:     Level: intermediate

370: .seealso: [](ch:svd), `SVDGetWhichSingularTriplets()`, `SVDWhich`
371: @*/
372: PetscErrorCode SVDSetWhichSingularTriplets(SVD svd,SVDWhich which)
373: {
374:   PetscFunctionBegin;
377:   switch (which) {
378:     case SVD_LARGEST:
379:     case SVD_SMALLEST:
380:       if (svd->which != which) {
381:         svd->state = SVD_STATE_INITIAL;
382:         svd->which = which;
383:       }
384:       break;
385:   default:
386:     SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'which' parameter");
387:   }
388:   PetscFunctionReturn(PETSC_SUCCESS);
389: }

391: /*@
392:     SVDGetWhichSingularTriplets - Returns which singular triplets are
393:     to be sought.

395:     Not Collective

397:     Input Parameter:
398: .   svd - the singular value solver context

400:     Output Parameter:
401: .   which - which singular triplets are to be sought

403:     Level: intermediate

405: .seealso: [](ch:svd), `SVDSetWhichSingularTriplets()`, `SVDWhich`
406: @*/
407: PetscErrorCode SVDGetWhichSingularTriplets(SVD svd,SVDWhich *which)
408: {
409:   PetscFunctionBegin;
411:   PetscAssertPointer(which,2);
412:   *which = svd->which;
413:   PetscFunctionReturn(PETSC_SUCCESS);
414: }

416: /*@C
417:    SVDSetConvergenceTestFunction - Sets a function to compute the error estimate
418:    used in the convergence test.

420:    Logically Collective

422:    Input Parameters:
423: +  svd     - the singular value solver context
424: .  conv    - the convergence test function, see `SVDConvergenceTestFn` for the calling sequence
425: .  ctx     - context for private data for the convergence routine (may be `NULL`)
426: -  destroy - a routine for destroying the context (may be `NULL`), see `PetscCtxDestroyFn`
427:              for the calling sequence

429:    Notes:
430:    When this is called with a user-defined function, then the convergence
431:    criterion is set to `SVD_CONV_USER`, see `SVDSetConvergenceTest()`.

433:    If the error estimate returned by the convergence test function is less than
434:    the tolerance, then the singular value is accepted as converged.

436:    Level: advanced

438: .seealso: [](ch:svd), `SVDSetConvergenceTest()`, `SVDSetTolerances()`
439: @*/
440: PetscErrorCode SVDSetConvergenceTestFunction(SVD svd,SVDConvergenceTestFn *conv,void *ctx,PetscCtxDestroyFn *destroy)
441: {
442:   PetscFunctionBegin;
444:   if (svd->convergeddestroy) PetscCall((*svd->convergeddestroy)(&svd->convergedctx));
445:   svd->convergeduser    = conv;
446:   svd->convergeddestroy = destroy;
447:   svd->convergedctx     = ctx;
448:   if (conv == SVDConvergedAbsolute) svd->conv = SVD_CONV_ABS;
449:   else if (conv == SVDConvergedRelative) svd->conv = SVD_CONV_REL;
450:   else if (conv == SVDConvergedNorm) svd->conv = SVD_CONV_NORM;
451:   else if (conv == SVDConvergedMaxIt) svd->conv = SVD_CONV_MAXIT;
452:   else {
453:     svd->conv      = SVD_CONV_USER;
454:     svd->converged = svd->convergeduser;
455:   }
456:   PetscFunctionReturn(PETSC_SUCCESS);
457: }

459: /*@
460:    SVDSetConvergenceTest - Specifies how to compute the error estimate
461:    used in the convergence test.

463:    Logically Collective

465:    Input Parameters:
466: +  svd  - the singular value solver context
467: -  conv - the type of convergence test, see `SVDConv` for possible values

469:    Options Database Keys:
470: +  -svd_conv_abs   - sets the absolute convergence test
471: .  -svd_conv_rel   - sets the convergence test relative to the singular value
472: .  -svd_conv_norm  - sets the convergence test relative to the matrix norms
473: .  -svd_conv_maxit - forces the maximum number of iterations as set by `-svd_max_it`
474: -  -svd_conv_user  - selects the user-defined convergence test

476:    Note:
477:    The default in standard SVD is `SVD_CONV_REL`, while in GSVD the default is `SVD_CONV_NORM`.

479:    Level: intermediate

481: .seealso: [](ch:svd), `SVDGetConvergenceTest()`, `SVDSetConvergenceTestFunction()`, `SVDSetStoppingTest()`, `SVDConv`
482: @*/
483: PetscErrorCode SVDSetConvergenceTest(SVD svd,SVDConv conv)
484: {
485:   PetscFunctionBegin;
488:   switch (conv) {
489:     case SVD_CONV_ABS:   svd->converged = SVDConvergedAbsolute; break;
490:     case SVD_CONV_REL:   svd->converged = SVDConvergedRelative; break;
491:     case SVD_CONV_NORM:  svd->converged = SVDConvergedNorm; break;
492:     case SVD_CONV_MAXIT: svd->converged = SVDConvergedMaxIt; break;
493:     case SVD_CONV_USER:
494:       PetscCheck(svd->convergeduser,PetscObjectComm((PetscObject)svd),PETSC_ERR_ORDER,"Must call SVDSetConvergenceTestFunction() first");
495:       svd->converged = svd->convergeduser;
496:       break;
497:     default:
498:       SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'conv' value");
499:   }
500:   svd->conv = conv;
501:   PetscFunctionReturn(PETSC_SUCCESS);
502: }

504: /*@
505:    SVDGetConvergenceTest - Gets the method used to compute the error estimate
506:    used in the convergence test.

508:    Not Collective

510:    Input Parameter:
511: .  svd   - the singular value solver context

513:    Output Parameter:
514: .  conv  - the type of convergence test

516:    Level: intermediate

518: .seealso: [](ch:svd), `SVDSetConvergenceTest()`, `SVDConv`
519: @*/
520: PetscErrorCode SVDGetConvergenceTest(SVD svd,SVDConv *conv)
521: {
522:   PetscFunctionBegin;
524:   PetscAssertPointer(conv,2);
525:   *conv = svd->conv;
526:   PetscFunctionReturn(PETSC_SUCCESS);
527: }

529: /*@C
530:    SVDSetStoppingTestFunction - Sets a function to decide when to stop the outer
531:    iteration of the singular value solver.

533:    Logically Collective

535:    Input Parameters:
536: +  svd     - the singular value solver context
537: .  stop    - the stopping test function, see `SVDStoppingTestFn` for the calling sequence
538: .  ctx     - context for private data for the stopping routine (may be `NULL`)
539: -  destroy - a routine for destroying the context (may be `NULL`), see `PetscCtxDestroyFn`
540:              for the calling sequence

542:    Note:
543:    When implementing a function for this, normal usage is to first call the
544:    default routine `SVDStoppingBasic()` and then set `reason` to `SVD_CONVERGED_USER`
545:    if some user-defined conditions have been met. To let the singular value solver
546:    continue iterating, the result must be left as `SVD_CONVERGED_ITERATING`.

548:    Level: advanced

550: .seealso: [](ch:svd), `SVDSetStoppingTest()`, `SVDStoppingBasic()`
551: @*/
552: PetscErrorCode SVDSetStoppingTestFunction(SVD svd,SVDStoppingTestFn *stop,void *ctx,PetscCtxDestroyFn *destroy)
553: {
554:   PetscFunctionBegin;
556:   if (svd->stoppingdestroy) PetscCall((*svd->stoppingdestroy)(&svd->stoppingctx));
557:   svd->stoppinguser    = stop;
558:   svd->stoppingdestroy = destroy;
559:   svd->stoppingctx     = ctx;
560:   if (stop == SVDStoppingBasic) PetscCall(SVDSetStoppingTest(svd,SVD_STOP_BASIC));
561:   else if (stop == SVDStoppingThreshold) PetscCall(SVDSetStoppingTest(svd,SVD_STOP_THRESHOLD));
562:   else {
563:     svd->stop     = SVD_STOP_USER;
564:     svd->stopping = svd->stoppinguser;
565:   }
566:   PetscFunctionReturn(PETSC_SUCCESS);
567: }

569: /*@
570:    SVDSetStoppingTest - Specifies how to decide the termination of the outer
571:    loop of the singular value solver.

573:    Logically Collective

575:    Input Parameters:
576: +  svd  - the singular value solver context
577: -  stop - the type of stopping test, see `SVDStop`

579:    Options Database Keys:
580: +  -svd_stop_basic     - sets the default stopping test
581: .  -svd_stop_threshold - sets the threshold stopping test
582: -  -svd_stop_user      - selects the user-defined stopping test

584:    Level: advanced

586: .seealso: [](ch:svd), `SVDGetStoppingTest()`, `SVDSetStoppingTestFunction()`, `SVDSetConvergenceTest()`, `SVDStop`
587: @*/
588: PetscErrorCode SVDSetStoppingTest(SVD svd,SVDStop stop)
589: {
590:   PetscFunctionBegin;
593:   switch (stop) {
594:     case SVD_STOP_BASIC: svd->stopping = SVDStoppingBasic; break;
595:     case SVD_STOP_THRESHOLD: svd->stopping = SVDStoppingThreshold; break;
596:     case SVD_STOP_USER:
597:       PetscCheck(svd->stoppinguser,PetscObjectComm((PetscObject)svd),PETSC_ERR_ORDER,"Must call SVDSetStoppingTestFunction() first");
598:       svd->stopping = svd->stoppinguser;
599:       break;
600:     default:
601:       SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'stop' value");
602:   }
603:   svd->stop = stop;
604:   PetscFunctionReturn(PETSC_SUCCESS);
605: }

607: /*@
608:    SVDGetStoppingTest - Gets the method used to decide the termination of the outer
609:    loop of the singular value solver.

611:    Not Collective

613:    Input Parameter:
614: .  svd   - the singular value solver context

616:    Output Parameter:
617: .  stop  - the type of stopping test

619:    Level: advanced

621: .seealso: [](ch:svd), `SVDSetStoppingTest()`, `SVDStop`
622: @*/
623: PetscErrorCode SVDGetStoppingTest(SVD svd,SVDStop *stop)
624: {
625:   PetscFunctionBegin;
627:   PetscAssertPointer(stop,2);
628:   *stop = svd->stop;
629:   PetscFunctionReturn(PETSC_SUCCESS);
630: }

632: /*@C
633:    SVDMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type
634:    indicated by the user.

636:    Collective

638:    Input Parameters:
639: +  svd      - the singular value solver context
640: .  opt      - the command line option for this monitor
641: .  name     - the monitor type one is seeking
642: .  ctx      - an optional user context for the monitor, or `NULL`
643: -  trackall - whether this monitor tracks all singular values or not

645:    Level: developer

647: .seealso: [](ch:svd), `SVDMonitorSet()`, `SVDSetTrackAll()`
648: @*/
649: PetscErrorCode SVDMonitorSetFromOptions(SVD svd,const char opt[],const char name[],void *ctx,PetscBool trackall)
650: {
651:   PetscErrorCode       (*mfunc)(SVD,PetscInt,PetscInt,PetscReal*,PetscReal*,PetscInt,void*);
652:   PetscErrorCode       (*cfunc)(PetscViewer,PetscViewerFormat,void*,PetscViewerAndFormat**);
653:   PetscErrorCode       (*dfunc)(PetscViewerAndFormat**);
654:   PetscViewerAndFormat *vf;
655:   PetscViewer          viewer;
656:   PetscViewerFormat    format;
657:   PetscViewerType      vtype;
658:   char                 key[PETSC_MAX_PATH_LEN];
659:   PetscBool            flg;

661:   PetscFunctionBegin;
662:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,opt,&viewer,&format,&flg));
663:   if (!flg) PetscFunctionReturn(PETSC_SUCCESS);

665:   PetscCall(PetscViewerGetType(viewer,&vtype));
666:   PetscCall(SlepcMonitorMakeKey_Internal(name,vtype,format,key));
667:   PetscCall(PetscFunctionListFind(SVDMonitorList,key,&mfunc));
668:   PetscCheck(mfunc,PetscObjectComm((PetscObject)svd),PETSC_ERR_SUP,"Specified viewer and format not supported");
669:   PetscCall(PetscFunctionListFind(SVDMonitorCreateList,key,&cfunc));
670:   PetscCall(PetscFunctionListFind(SVDMonitorDestroyList,key,&dfunc));
671:   if (!cfunc) cfunc = PetscViewerAndFormatCreate_Internal;
672:   if (!dfunc) dfunc = PetscViewerAndFormatDestroy;

674:   PetscCall((*cfunc)(viewer,format,ctx,&vf));
675:   PetscCall(PetscViewerDestroy(&viewer));
676:   PetscCall(SVDMonitorSet(svd,mfunc,vf,(PetscCtxDestroyFn*)dfunc));
677:   if (trackall) PetscCall(SVDSetTrackAll(svd,PETSC_TRUE));
678:   PetscFunctionReturn(PETSC_SUCCESS);
679: }

681: /*@
682:    SVDSetFromOptions - Sets `SVD` options from the options database.
683:    This routine must be called before `SVDSetUp()` if the user is to be
684:    allowed to configure the solver.

686:    Collective

688:    Input Parameter:
689: .  svd - the singular value solver context

691:    Note:
692:    To see all options, run your program with the `-help` option.

694:    Level: beginner

696: .seealso: [](ch:svd), `SVDSetOptionsPrefix()`
697: @*/
698: PetscErrorCode SVDSetFromOptions(SVD svd)
699: {
700:   char           type[256];
701:   PetscBool      set,flg,val,flg1,flg2,flg3;
702:   PetscInt       i,j,k;
703:   PetscReal      r;

705:   PetscFunctionBegin;
707:   PetscCall(SVDRegisterAll());
708:   PetscObjectOptionsBegin((PetscObject)svd);
709:     PetscCall(PetscOptionsFList("-svd_type","SVD solver method","SVDSetType",SVDList,(char*)(((PetscObject)svd)->type_name?((PetscObject)svd)->type_name:SVDCROSS),type,sizeof(type),&flg));
710:     if (flg) PetscCall(SVDSetType(svd,type));
711:     else if (!((PetscObject)svd)->type_name) PetscCall(SVDSetType(svd,SVDCROSS));

713:     PetscCall(PetscOptionsBoolGroupBegin("-svd_standard","Singular value decomposition (SVD)","SVDSetProblemType",&flg));
714:     if (flg) PetscCall(SVDSetProblemType(svd,SVD_STANDARD));
715:     PetscCall(PetscOptionsBoolGroup("-svd_generalized","Generalized singular value decomposition (GSVD)","SVDSetProblemType",&flg));
716:     if (flg) PetscCall(SVDSetProblemType(svd,SVD_GENERALIZED));
717:     PetscCall(PetscOptionsBoolGroupEnd("-svd_hyperbolic","Hyperbolic singular value decomposition (HSVD)","SVDSetProblemType",&flg));
718:     if (flg) PetscCall(SVDSetProblemType(svd,SVD_HYPERBOLIC));

720:     PetscCall(PetscOptionsBool("-svd_implicittranspose","Handle matrix transpose implicitly","SVDSetImplicitTranspose",svd->impltrans,&val,&flg));
721:     if (flg) PetscCall(SVDSetImplicitTranspose(svd,val));

723:     i = svd->max_it;
724:     PetscCall(PetscOptionsInt("-svd_max_it","Maximum number of iterations","SVDSetTolerances",svd->max_it,&i,&flg1));
725:     r = svd->tol;
726:     PetscCall(PetscOptionsReal("-svd_tol","Tolerance","SVDSetTolerances",SlepcDefaultTol(svd->tol),&r,&flg2));
727:     if (flg1 || flg2) PetscCall(SVDSetTolerances(svd,r,i));

729:     r = svd->thres;
730:     PetscCall(PetscOptionsReal("-svd_threshold_absolute","Absolute threshold","SVDSetThreshold",r,&r,&flg));
731:     if (flg) PetscCall(SVDSetThreshold(svd,r,PETSC_FALSE));
732:     PetscCall(PetscOptionsReal("-svd_threshold_relative","Relative threshold","SVDSetThreshold",r,&r,&flg));
733:     if (flg) PetscCall(SVDSetThreshold(svd,r,PETSC_TRUE));

735:     PetscCall(PetscOptionsBoolGroupBegin("-svd_conv_abs","Absolute error convergence test","SVDSetConvergenceTest",&flg));
736:     if (flg) PetscCall(SVDSetConvergenceTest(svd,SVD_CONV_ABS));
737:     PetscCall(PetscOptionsBoolGroup("-svd_conv_rel","Relative error convergence test","SVDSetConvergenceTest",&flg));
738:     if (flg) PetscCall(SVDSetConvergenceTest(svd,SVD_CONV_REL));
739:     PetscCall(PetscOptionsBoolGroup("-svd_conv_norm","Convergence test relative to the matrix norms","SVDSetConvergenceTest",&flg));
740:     if (flg) PetscCall(SVDSetConvergenceTest(svd,SVD_CONV_NORM));
741:     PetscCall(PetscOptionsBoolGroup("-svd_conv_maxit","Maximum iterations convergence test","SVDSetConvergenceTest",&flg));
742:     if (flg) PetscCall(SVDSetConvergenceTest(svd,SVD_CONV_MAXIT));
743:     PetscCall(PetscOptionsBoolGroupEnd("-svd_conv_user","User-defined convergence test","SVDSetConvergenceTest",&flg));
744:     if (flg) PetscCall(SVDSetConvergenceTest(svd,SVD_CONV_USER));

746:     PetscCall(PetscOptionsBoolGroupBegin("-svd_stop_basic","Stop iteration if all singular values converged or max_it reached","SVDSetStoppingTest",&flg));
747:     if (flg) PetscCall(SVDSetStoppingTest(svd,SVD_STOP_BASIC));
748:     PetscCall(PetscOptionsBoolGroup("-svd_stop_threshold","Stop iteration if a converged singular value is below/above the threshold","SVDSetStoppingTest",&flg));
749:     if (flg) PetscCall(SVDSetStoppingTest(svd,SVD_STOP_THRESHOLD));
750:     PetscCall(PetscOptionsBoolGroupEnd("-svd_stop_user","User-defined stopping test","SVDSetStoppingTest",&flg));
751:     if (flg) PetscCall(SVDSetStoppingTest(svd,SVD_STOP_USER));

753:     i = svd->nsv;
754:     PetscCall(PetscOptionsInt("-svd_nsv","Number of singular values to compute","SVDSetDimensions",svd->nsv,&i,&flg1));
755:     if (!flg1) i = PETSC_CURRENT;
756:     j = svd->ncv;
757:     PetscCall(PetscOptionsInt("-svd_ncv","Number of basis vectors","SVDSetDimensions",svd->ncv,&j,&flg2));
758:     k = svd->mpd;
759:     PetscCall(PetscOptionsInt("-svd_mpd","Maximum dimension of projected problem","SVDSetDimensions",svd->mpd,&k,&flg3));
760:     if (flg1 || flg2 || flg3) PetscCall(SVDSetDimensions(svd,i,j,k));

762:     PetscCall(PetscOptionsBoolGroupBegin("-svd_largest","Compute largest singular values","SVDSetWhichSingularTriplets",&flg));
763:     if (flg) PetscCall(SVDSetWhichSingularTriplets(svd,SVD_LARGEST));
764:     PetscCall(PetscOptionsBoolGroupEnd("-svd_smallest","Compute smallest singular values","SVDSetWhichSingularTriplets",&flg));
765:     if (flg) PetscCall(SVDSetWhichSingularTriplets(svd,SVD_SMALLEST));

767:     /* -----------------------------------------------------------------------*/
768:     /*
769:       Cancels all monitors hardwired into code before call to SVDSetFromOptions()
770:     */
771:     PetscCall(PetscOptionsBool("-svd_monitor_cancel","Remove any hardwired monitor routines","SVDMonitorCancel",PETSC_FALSE,&flg,&set));
772:     if (set && flg) PetscCall(SVDMonitorCancel(svd));
773:     PetscCall(SVDMonitorSetFromOptions(svd,"-svd_monitor","first_approximation",NULL,PETSC_FALSE));
774:     PetscCall(SVDMonitorSetFromOptions(svd,"-svd_monitor_all","all_approximations",NULL,PETSC_TRUE));
775:     PetscCall(SVDMonitorSetFromOptions(svd,"-svd_monitor_conv","convergence_history",NULL,PETSC_FALSE));
776:     PetscCall(SVDMonitorSetFromOptions(svd,"-svd_monitor_conditioning","conditioning",NULL,PETSC_FALSE));

778:     /* -----------------------------------------------------------------------*/
779:     PetscCall(PetscOptionsName("-svd_view","Print detailed information on solver used","SVDView",&set));
780:     PetscCall(PetscOptionsName("-svd_view_vectors","View computed singular vectors","SVDVectorsView",&set));
781:     PetscCall(PetscOptionsName("-svd_view_values","View computed singular values","SVDValuesView",&set));
782:     PetscCall(PetscOptionsName("-svd_converged_reason","Print reason for convergence, and number of iterations","SVDConvergedReasonView",&set));
783:     PetscCall(PetscOptionsName("-svd_error_absolute","Print absolute errors of each singular triplet","SVDErrorView",&set));
784:     PetscCall(PetscOptionsName("-svd_error_relative","Print relative errors of each singular triplet","SVDErrorView",&set));
785:     PetscCall(PetscOptionsName("-svd_error_norm","Print errors relative to the matrix norms of each singular triplet","SVDErrorView",&set));

787:     PetscTryTypeMethod(svd,setfromoptions,PetscOptionsObject);
788:     PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)svd,PetscOptionsObject));
789:   PetscOptionsEnd();

791:   if (!svd->V) PetscCall(SVDGetBV(svd,&svd->V,NULL));
792:   PetscCall(BVSetFromOptions(svd->V));
793:   if (!svd->U) PetscCall(SVDGetBV(svd,NULL,&svd->U));
794:   PetscCall(BVSetFromOptions(svd->U));
795:   if (!svd->ds) PetscCall(SVDGetDS(svd,&svd->ds));
796:   PetscCall(SVDSetDSType(svd));
797:   PetscCall(DSSetFromOptions(svd->ds));
798:   PetscFunctionReturn(PETSC_SUCCESS);
799: }

801: /*@
802:    SVDSetProblemType - Specifies the type of the singular value problem.

804:    Logically Collective

806:    Input Parameters:
807: +  svd  - the singular value solver context
808: -  type - a known type of singular value problem

810:    Options Database Keys:
811: +  -svd_standard    - standard singular value decomposition (SVD)
812: .  -svd_generalized - generalized singular value problem (GSVD)
813: -  -svd_hyperbolic  - hyperbolic singular value problem (HSVD)

815:    Note:
816:    The GSVD requires that two matrices have been passed via `SVDSetOperators()`.
817:    The HSVD requires that a signature matrix has been passed via `SVDSetSignature()`.

819:    Level: intermediate

821: .seealso: [](ch:svd), `SVDSetOperators()`, `SVDSetSignature()`, `SVDSetType()`, `SVDGetProblemType()`, `SVDProblemType`
822: @*/
823: PetscErrorCode SVDSetProblemType(SVD svd,SVDProblemType type)
824: {
825:   PetscFunctionBegin;
828:   if (type == svd->problem_type) PetscFunctionReturn(PETSC_SUCCESS);
829:   switch (type) {
830:     case SVD_STANDARD:
831:       svd->isgeneralized = PETSC_FALSE;
832:       svd->ishyperbolic  = PETSC_FALSE;
833:       break;
834:     case SVD_GENERALIZED:
835:       svd->isgeneralized = PETSC_TRUE;
836:       svd->ishyperbolic  = PETSC_FALSE;
837:       break;
838:     case SVD_HYPERBOLIC:
839:       svd->isgeneralized = PETSC_FALSE;
840:       svd->ishyperbolic  = PETSC_TRUE;
841:       break;
842:     default:
843:       SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_WRONG,"Unknown singular value problem type");
844:   }
845:   svd->problem_type = type;
846:   svd->state = SVD_STATE_INITIAL;
847:   PetscFunctionReturn(PETSC_SUCCESS);
848: }

850: /*@
851:    SVDGetProblemType - Gets the problem type from the SVD object.

853:    Not Collective

855:    Input Parameter:
856: .  svd - the singular value solver context

858:    Output Parameter:
859: .  type - the problem type

861:    Level: intermediate

863: .seealso: [](ch:svd), `SVDSetProblemType()`, `SVDProblemType`
864: @*/
865: PetscErrorCode SVDGetProblemType(SVD svd,SVDProblemType *type)
866: {
867:   PetscFunctionBegin;
869:   PetscAssertPointer(type,2);
870:   *type = svd->problem_type;
871:   PetscFunctionReturn(PETSC_SUCCESS);
872: }

874: /*@
875:    SVDIsGeneralized - Ask if the SVD object corresponds to a generalized
876:    singular value problem.

878:    Not Collective

880:    Input Parameter:
881: .  svd - the singular value solver context

883:    Output Parameter:
884: .  is - the answer

886:    Level: intermediate

888: .seealso: [](ch:svd), `SVDIsHyperbolic()`
889: @*/
890: PetscErrorCode SVDIsGeneralized(SVD svd,PetscBool* is)
891: {
892:   PetscFunctionBegin;
894:   PetscAssertPointer(is,2);
895:   *is = svd->isgeneralized;
896:   PetscFunctionReturn(PETSC_SUCCESS);
897: }

899: /*@
900:    SVDIsHyperbolic - Ask if the SVD object corresponds to a hyperbolic
901:    singular value problem.

903:    Not Collective

905:    Input Parameter:
906: .  svd - the singular value solver context

908:    Output Parameter:
909: .  is - the answer

911:    Level: intermediate

913: .seealso: [](ch:svd), `SVDIsGeneralized()`
914: @*/
915: PetscErrorCode SVDIsHyperbolic(SVD svd,PetscBool* is)
916: {
917:   PetscFunctionBegin;
919:   PetscAssertPointer(is,2);
920:   *is = svd->ishyperbolic;
921:   PetscFunctionReturn(PETSC_SUCCESS);
922: }

924: /*@
925:    SVDSetTrackAll - Specifies if the solver must compute the residual norm of all
926:    approximate singular value or not.

928:    Logically Collective

930:    Input Parameters:
931: +  svd      - the singular value solver context
932: -  trackall - whether to compute all residuals or not

934:    Notes:
935:    If the user sets `trackall`=`PETSC_TRUE` then the solver computes (or estimates)
936:    the residual norm for each singular value approximation. Computing the residual is
937:    usually an expensive operation and solvers commonly compute only the residual
938:    associated to the first unconverged singular value.

940:    The option `-svd_monitor_all` automatically activates this option.

942:    Level: developer

944: .seealso: [](ch:svd), `SVDGetTrackAll()`
945: @*/
946: PetscErrorCode SVDSetTrackAll(SVD svd,PetscBool trackall)
947: {
948:   PetscFunctionBegin;
951:   svd->trackall = trackall;
952:   PetscFunctionReturn(PETSC_SUCCESS);
953: }

955: /*@
956:    SVDGetTrackAll - Returns the flag indicating whether all residual norms must
957:    be computed or not.

959:    Not Collective

961:    Input Parameter:
962: .  svd - the singular value solver context

964:    Output Parameter:
965: .  trackall - the returned flag

967:    Level: developer

969: .seealso: [](ch:svd), `SVDSetTrackAll()`
970: @*/
971: PetscErrorCode SVDGetTrackAll(SVD svd,PetscBool *trackall)
972: {
973:   PetscFunctionBegin;
975:   PetscAssertPointer(trackall,2);
976:   *trackall = svd->trackall;
977:   PetscFunctionReturn(PETSC_SUCCESS);
978: }

980: /*@
981:    SVDSetOptionsPrefix - Sets the prefix used for searching for all
982:    `SVD` options in the database.

984:    Logically Collective

986:    Input Parameters:
987: +  svd    - the singular value solver context
988: -  prefix - the prefix string to prepend to all `SVD` option requests

990:    Notes:
991:    A hyphen (-) must NOT be given at the beginning of the prefix name.
992:    The first character of all runtime options is AUTOMATICALLY the
993:    hyphen.

995:    For example, to distinguish between the runtime options for two
996:    different `SVD` contexts, one could call
997: .vb
998:    SVDSetOptionsPrefix(svd1,"svd1_")
999:    SVDSetOptionsPrefix(svd2,"svd2_")
1000: .ve

1002:    Level: advanced

1004: .seealso: [](ch:svd), `SVDAppendOptionsPrefix()`, `SVDGetOptionsPrefix()`
1005: @*/
1006: PetscErrorCode SVDSetOptionsPrefix(SVD svd,const char prefix[])
1007: {
1008:   PetscFunctionBegin;
1010:   if (!svd->V) PetscCall(SVDGetBV(svd,&svd->V,&svd->U));
1011:   PetscCall(BVSetOptionsPrefix(svd->V,prefix));
1012:   PetscCall(BVSetOptionsPrefix(svd->U,prefix));
1013:   if (!svd->ds) PetscCall(SVDGetDS(svd,&svd->ds));
1014:   PetscCall(DSSetOptionsPrefix(svd->ds,prefix));
1015:   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)svd,prefix));
1016:   PetscFunctionReturn(PETSC_SUCCESS);
1017: }

1019: /*@
1020:    SVDAppendOptionsPrefix - Appends to the prefix used for searching for all
1021:    `SVD` options in the database.

1023:    Logically Collective

1025:    Input Parameters:
1026: +  svd    - the singular value solver context
1027: -  prefix - the prefix string to prepend to all `SVD` option requests

1029:    Notes:
1030:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1031:    The first character of all runtime options is AUTOMATICALLY the hyphen.

1033:    Level: advanced

1035: .seealso: [](ch:svd), `SVDSetOptionsPrefix()`, `SVDGetOptionsPrefix()`
1036: @*/
1037: PetscErrorCode SVDAppendOptionsPrefix(SVD svd,const char prefix[])
1038: {
1039:   PetscFunctionBegin;
1041:   if (!svd->V) PetscCall(SVDGetBV(svd,&svd->V,&svd->U));
1042:   PetscCall(BVAppendOptionsPrefix(svd->V,prefix));
1043:   PetscCall(BVAppendOptionsPrefix(svd->U,prefix));
1044:   if (!svd->ds) PetscCall(SVDGetDS(svd,&svd->ds));
1045:   PetscCall(DSAppendOptionsPrefix(svd->ds,prefix));
1046:   PetscCall(PetscObjectAppendOptionsPrefix((PetscObject)svd,prefix));
1047:   PetscFunctionReturn(PETSC_SUCCESS);
1048: }

1050: /*@
1051:    SVDGetOptionsPrefix - Gets the prefix used for searching for all
1052:    `SVD` options in the database.

1054:    Not Collective

1056:    Input Parameter:
1057: .  svd - the singular value solver context

1059:    Output Parameter:
1060: .  prefix - pointer to the prefix string used is returned

1062:    Level: advanced

1064: .seealso: [](ch:svd), `SVDSetOptionsPrefix()`, `SVDAppendOptionsPrefix()`
1065: @*/
1066: PetscErrorCode SVDGetOptionsPrefix(SVD svd,const char *prefix[])
1067: {
1068:   PetscFunctionBegin;
1070:   PetscAssertPointer(prefix,2);
1071:   PetscCall(PetscObjectGetOptionsPrefix((PetscObject)svd,prefix));
1072:   PetscFunctionReturn(PETSC_SUCCESS);
1073: }