Actual source code: svdview.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:    The SVD routines related to various viewers
 12: */

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

 17: /*@
 18:    SVDView - Prints the `SVD` data structure.

 20:    Collective

 22:    Input Parameters:
 23: +  svd - the singular value solver context
 24: -  viewer - optional visualization context

 26:    Options Database Key:
 27: .  -svd_view - calls `SVDView()` at end of `SVDSolve()`

 29:    Notes:
 30:    The available visualization contexts include
 31: +     `PETSC_VIEWER_STDOUT_SELF` - standard output (default)
 32: -     `PETSC_VIEWER_STDOUT_WORLD` - synchronized standard output where only the
 33:          first process opens the file; all other processes send their data to the
 34:          first one to print

 36:    The user can open an alternative visualization context with `PetscViewerASCIIOpen()`
 37:    to output to a specified file.

 39:    Level: beginner

 41: .seealso: [](ch:svd), `SVDCreate()`, `SVDViewFromOptions()`, `EPSView()`
 42: @*/
 43: PetscErrorCode SVDView(SVD svd,PetscViewer viewer)
 44: {
 45:   const char     *type=NULL;
 46:   PetscBool      isascii,isshell,isexternal;

 48:   PetscFunctionBegin;
 50:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)svd),&viewer));
 52:   PetscCheckSameComm(svd,1,viewer,2);

 54:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii));
 55:   if (isascii) {
 56:     PetscCall(PetscObjectPrintClassNamePrefixType((PetscObject)svd,viewer));
 57:     PetscCall(PetscViewerASCIIPushTab(viewer));
 58:     PetscTryTypeMethod(svd,view,viewer);
 59:     PetscCall(PetscViewerASCIIPopTab(viewer));
 60:     if (svd->problem_type) {
 61:       switch (svd->problem_type) {
 62:         case SVD_STANDARD:    type = "(standard) singular value problem"; break;
 63:         case SVD_GENERALIZED: type = "generalized singular value problem"; break;
 64:         case SVD_HYPERBOLIC:  type = "hyperbolic singular value problem"; break;
 65:       }
 66:     } else type = "not yet set";
 67:     PetscCall(PetscViewerASCIIPrintf(viewer,"  problem type: %s\n",type));
 68:     PetscCall(PetscViewerASCIIPrintf(viewer,"  transpose mode: %s\n",svd->impltrans?"implicit":"explicit"));
 69:     if (svd->which == SVD_LARGEST) PetscCall(PetscViewerASCIIPrintf(viewer,"  selected portion of the spectrum: largest\n"));
 70:     else PetscCall(PetscViewerASCIIPrintf(viewer,"  selected portion of the spectrum: smallest\n"));
 71:     if (svd->stop==SVD_STOP_THRESHOLD) PetscCall(PetscViewerASCIIPrintf(viewer,"  computing singular values %s the threshold: %g%s\n",svd->which==SVD_LARGEST?"above":"below",(double)svd->thres,svd->threlative?" (relative)":""));
 72:     if (svd->nsv) PetscCall(PetscViewerASCIIPrintf(viewer,"  number of singular values (nsv): %" PetscInt_FMT "\n",svd->nsv));
 73:     PetscCall(PetscViewerASCIIPrintf(viewer,"  number of column vectors (ncv): %" PetscInt_FMT "\n",svd->ncv));
 74:     PetscCall(PetscViewerASCIIPrintf(viewer,"  maximum dimension of projected problem (mpd): %" PetscInt_FMT "\n",svd->mpd));
 75:     PetscCall(PetscViewerASCIIPrintf(viewer,"  maximum number of iterations: %" PetscInt_FMT "\n",svd->max_it));
 76:     PetscCall(PetscViewerASCIIPrintf(viewer,"  tolerance: %g\n",(double)svd->tol));
 77:     PetscCall(PetscViewerASCIIPrintf(viewer,"  convergence test: "));
 78:     PetscCall(PetscViewerASCIIUseTabs(viewer,PETSC_FALSE));
 79:     switch (svd->conv) {
 80:     case SVD_CONV_ABS:
 81:       PetscCall(PetscViewerASCIIPrintf(viewer,"absolute\n"));break;
 82:     case SVD_CONV_REL:
 83:       PetscCall(PetscViewerASCIIPrintf(viewer,"relative to the singular value\n"));break;
 84:     case SVD_CONV_NORM:
 85:       PetscCall(PetscViewerASCIIPrintf(viewer,"relative to the matrix norms\n"));
 86:       PetscCall(PetscViewerASCIIPrintf(viewer,"  computed matrix norms: norm(A)=%g",(double)svd->nrma));
 87:       if (svd->isgeneralized) PetscCall(PetscViewerASCIIPrintf(viewer,", norm(B)=%g",(double)svd->nrmb));
 88:       PetscCall(PetscViewerASCIIPrintf(viewer,"\n"));
 89:       break;
 90:     case SVD_CONV_MAXIT:
 91:       PetscCall(PetscViewerASCIIPrintf(viewer,"maximum number of iterations\n"));break;
 92:     case SVD_CONV_USER:
 93:       PetscCall(PetscViewerASCIIPrintf(viewer,"user-defined\n"));break;
 94:     }
 95:     PetscCall(PetscViewerASCIIUseTabs(viewer,PETSC_TRUE));
 96:     if (svd->nini) PetscCall(PetscViewerASCIIPrintf(viewer,"  dimension of user-provided initial space: %" PetscInt_FMT "\n",PetscAbs(svd->nini)));
 97:     if (svd->ninil) PetscCall(PetscViewerASCIIPrintf(viewer,"  dimension of user-provided initial left space: %" PetscInt_FMT "\n",PetscAbs(svd->ninil)));
 98:   } else PetscTryTypeMethod(svd,view,viewer);
 99:   PetscCall(PetscObjectTypeCompareAny((PetscObject)svd,&isshell,SVDCROSS,SVDCYCLIC,""));
100:   PetscCall(PetscObjectTypeCompareAny((PetscObject)svd,&isexternal,SVDSCALAPACK,SVDKSVD,SVDELEMENTAL,SVDPRIMME,""));
101:   if (!isshell && !isexternal) {
102:     PetscCall(PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO));
103:     if (!svd->V) PetscCall(SVDGetBV(svd,&svd->V,NULL));
104:     PetscCall(BVView(svd->V,viewer));
105:     if (!svd->ds) PetscCall(SVDGetDS(svd,&svd->ds));
106:     PetscCall(DSView(svd->ds,viewer));
107:     PetscCall(PetscViewerPopFormat(viewer));
108:   }
109:   PetscFunctionReturn(PETSC_SUCCESS);
110: }

112: /*@
113:    SVDViewFromOptions - View (print) an `SVD` object based on values in the options database.

115:    Collective

117:    Input Parameters:
118: +  svd  - the singular value solver context
119: .  obj  - optional object that provides the options prefix used to query the options database
120: -  name - command line option

122:    Level: intermediate

124: .seealso: [](ch:svd), `SVDView()`, `SVDCreate()`, `PetscObjectViewFromOptions()`
125: @*/
126: PetscErrorCode SVDViewFromOptions(SVD svd,PetscObject obj,const char name[])
127: {
128:   PetscFunctionBegin;
130:   PetscCall(PetscObjectViewFromOptions((PetscObject)svd,obj,name));
131:   PetscFunctionReturn(PETSC_SUCCESS);
132: }

134: /*@
135:    SVDConvergedReasonView - Displays the reason an `SVD` solve converged or diverged.

137:    Collective

139:    Input Parameters:
140: +  svd - the singular value solver context
141: -  viewer - the viewer to display the reason

143:    Options Database Key:
144: .  -svd_converged_reason - print reason for convergence/divergence, and number of iterations

146:    Notes:
147:    Use `SVDConvergedReasonViewFromOptions()` to display the reason based on values
148:    in the options database.

150:    To change the format of the output call `PetscViewerPushFormat()` before this
151:    call. Use `PETSC_VIEWER_DEFAULT` for the default, or `PETSC_VIEWER_FAILED` to only
152:    display a reason if it fails. The latter can be set in the command line with
153:    `-svd_converged_reason ::failed`.

155:    Level: intermediate

157: .seealso: [](ch:svd), `SVDSetTolerances()`, `SVDGetIterationNumber()`, `SVDConvergedReasonViewFromOptions()`
158: @*/
159: PetscErrorCode SVDConvergedReasonView(SVD svd,PetscViewer viewer)
160: {
161:   PetscBool         isAscii;
162:   PetscViewerFormat format;

164:   PetscFunctionBegin;
165:   if (!viewer) viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)svd));
166:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isAscii));
167:   if (isAscii) {
168:     PetscCall(PetscViewerGetFormat(viewer,&format));
169:     PetscCall(PetscViewerASCIIAddTab(viewer,((PetscObject)svd)->tablevel));
170:     if (svd->reason > 0 && format != PETSC_VIEWER_FAILED) PetscCall(PetscViewerASCIIPrintf(viewer,"%s SVD solve converged (%" PetscInt_FMT " singular triplet%s) due to %s; iterations %" PetscInt_FMT "\n",((PetscObject)svd)->prefix?((PetscObject)svd)->prefix:"",svd->nconv,(svd->nconv>1)?"s":"",SVDConvergedReasons[svd->reason],svd->its));
171:     else if (svd->reason <= 0) PetscCall(PetscViewerASCIIPrintf(viewer,"%s SVD solve did not converge due to %s; iterations %" PetscInt_FMT "\n",((PetscObject)svd)->prefix?((PetscObject)svd)->prefix:"",SVDConvergedReasons[svd->reason],svd->its));
172:     PetscCall(PetscViewerASCIISubtractTab(viewer,((PetscObject)svd)->tablevel));
173:   }
174:   PetscFunctionReturn(PETSC_SUCCESS);
175: }

177: /*@
178:    SVDConvergedReasonViewFromOptions - Processes command line options to determine if/how
179:    the `SVD` converged reason is to be viewed.

181:    Collective

183:    Input Parameter:
184: .  svd - the singular value solver context

186:    Level: intermediate

188: .seealso: [](ch:svd), `SVDConvergedReasonView()`
189: @*/
190: PetscErrorCode SVDConvergedReasonViewFromOptions(SVD svd)
191: {
192:   PetscViewer       viewer;
193:   PetscBool         flg;
194:   static PetscBool  incall = PETSC_FALSE;
195:   PetscViewerFormat format;

197:   PetscFunctionBegin;
198:   if (incall) PetscFunctionReturn(PETSC_SUCCESS);
199:   incall = PETSC_TRUE;
200:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,"-svd_converged_reason",&viewer,&format,&flg));
201:   if (flg) {
202:     PetscCall(PetscViewerPushFormat(viewer,format));
203:     PetscCall(SVDConvergedReasonView(svd,viewer));
204:     PetscCall(PetscViewerPopFormat(viewer));
205:     PetscCall(PetscViewerDestroy(&viewer));
206:   }
207:   incall = PETSC_FALSE;
208:   PetscFunctionReturn(PETSC_SUCCESS);
209: }

211: static PetscErrorCode SVDErrorView_ASCII(SVD svd,SVDErrorType etype,PetscViewer viewer)
212: {
213:   PetscReal      error,sigma;
214:   PetscInt       i,j,numsv;

216:   PetscFunctionBegin;
217:   numsv = svd->stop==SVD_STOP_THRESHOLD? svd->nconv: svd->nsv;
218:   if (svd->nconv<numsv) {
219:     PetscCall(PetscViewerASCIIPrintf(viewer," Problem: less than %" PetscInt_FMT " singular values converged\n\n",numsv));
220:     PetscFunctionReturn(PETSC_SUCCESS);
221:   }
222:   for (i=0;i<numsv;i++) {
223:     PetscCall(SVDComputeError(svd,i,etype,&error));
224:     if (error>=5.0*svd->tol) {
225:       PetscCall(PetscViewerASCIIPrintf(viewer," Problem: some of the first %" PetscInt_FMT " relative errors are higher than the tolerance\n\n",numsv));
226:       PetscFunctionReturn(PETSC_SUCCESS);
227:     }
228:   }
229:   PetscCall(PetscViewerASCIIPrintf(viewer," All %s%ssingular values computed up to the required tolerance:",svd->stop==SVD_STOP_THRESHOLD?"":"requested ",svd->isgeneralized?"generalized ":""));
230:   for (i=0;i<=(numsv-1)/8;i++) {
231:     PetscCall(PetscViewerASCIIPrintf(viewer,"\n     "));
232:     for (j=0;j<PetscMin(8,numsv-8*i);j++) {
233:       PetscCall(SVDGetSingularTriplet(svd,8*i+j,&sigma,NULL,NULL));
234:       PetscCall(PetscViewerASCIIPrintf(viewer,"%.5f",(double)sigma));
235:       if (8*i+j+1<numsv) PetscCall(PetscViewerASCIIPrintf(viewer,", "));
236:     }
237:   }
238:   PetscCall(PetscViewerASCIIPrintf(viewer,"\n\n"));
239:   PetscFunctionReturn(PETSC_SUCCESS);
240: }

242: static PetscErrorCode SVDErrorView_DETAIL(SVD svd,SVDErrorType etype,PetscViewer viewer)
243: {
244:   PetscReal      error,sigma;
245:   PetscInt       i;
246:   char           ex[30],sep[]=" ---------------------- --------------------\n";

248:   PetscFunctionBegin;
249:   if (!svd->nconv) PetscFunctionReturn(PETSC_SUCCESS);
250:   switch (etype) {
251:     case SVD_ERROR_ABSOLUTE:
252:       PetscCall(PetscSNPrintf(ex,sizeof(ex)," absolute error"));
253:       break;
254:     case SVD_ERROR_RELATIVE:
255:       PetscCall(PetscSNPrintf(ex,sizeof(ex)," relative error"));
256:       break;
257:     case SVD_ERROR_NORM:
258:       if (svd->isgeneralized) PetscCall(PetscSNPrintf(ex,sizeof(ex)," ||r||/||[A;B]||"));
259:       else PetscCall(PetscSNPrintf(ex,sizeof(ex),"  ||r||/||A||"));
260:       break;
261:   }
262:   PetscCall(PetscViewerASCIIPrintf(viewer,"%s          sigma           %s\n%s",sep,ex,sep));
263:   for (i=0;i<svd->nconv;i++) {
264:     PetscCall(SVDGetSingularTriplet(svd,i,&sigma,NULL,NULL));
265:     PetscCall(SVDComputeError(svd,i,etype,&error));
266:     PetscCall(PetscViewerASCIIPrintf(viewer,"       % 6f          %12g\n",(double)sigma,(double)error));
267:   }
268:   PetscCall(PetscViewerASCIIPrintf(viewer,"%s",sep));
269:   PetscFunctionReturn(PETSC_SUCCESS);
270: }

272: static PetscErrorCode SVDErrorView_MATLAB(SVD svd,SVDErrorType etype,PetscViewer viewer)
273: {
274:   PetscReal      error;
275:   PetscInt       i;
276:   const char     *name;

278:   PetscFunctionBegin;
279:   PetscCall(PetscObjectGetName((PetscObject)svd,&name));
280:   PetscCall(PetscViewerASCIIPrintf(viewer,"Error_%s = [\n",name));
281:   for (i=0;i<svd->nconv;i++) {
282:     PetscCall(SVDComputeError(svd,i,etype,&error));
283:     PetscCall(PetscViewerASCIIPrintf(viewer,"%18.16e\n",(double)error));
284:   }
285:   PetscCall(PetscViewerASCIIPrintf(viewer,"];\n"));
286:   PetscFunctionReturn(PETSC_SUCCESS);
287: }

289: /*@
290:    SVDErrorView - Displays the errors associated with the computed solution
291:    (as well as the singular values).

293:    Collective

295:    Input Parameters:
296: +  svd    - the singular value solver context
297: .  etype  - error type
298: -  viewer - optional visualization context

300:    Options Database Keys:
301: +  -svd_error_absolute - print absolute errors of each singular triplet
302: .  -svd_error_relative - print relative errors of each singular triplet
303: -  -svd_error_norm     - print errors relative to the matrix norms of each singular triplet

305:    Notes:
306:    By default, this function checks the error of all singular triplets and prints
307:    the singular values if all of them are below the requested tolerance.
308:    If the viewer has format `PETSC_VIEWER_ASCII_INFO_DETAIL` then a table with
309:    singular values and corresponding errors is printed.

311:    All the command-line options listed above admit an optional argument
312:    specifying the viewer type and options. For instance, use
313:    `-svd_error_relative :myerr.m:ascii_matlab` to save the errors in a file
314:    that can be executed in Matlab.

316:    Level: intermediate

318: .seealso: [](ch:svd), `SVDSolve()`, `SVDValuesView()`, `SVDVectorsView()`
319: @*/
320: PetscErrorCode SVDErrorView(SVD svd,SVDErrorType etype,PetscViewer viewer)
321: {
322:   PetscBool         isascii;
323:   PetscViewerFormat format;

325:   PetscFunctionBegin;
327:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)svd),&viewer));
329:   PetscCheckSameComm(svd,1,viewer,3);
330:   SVDCheckSolved(svd,1);
331:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii));
332:   if (!isascii) PetscFunctionReturn(PETSC_SUCCESS);

334:   PetscCall(PetscViewerGetFormat(viewer,&format));
335:   switch (format) {
336:     case PETSC_VIEWER_DEFAULT:
337:     case PETSC_VIEWER_ASCII_INFO:
338:       PetscCall(SVDErrorView_ASCII(svd,etype,viewer));
339:       break;
340:     case PETSC_VIEWER_ASCII_INFO_DETAIL:
341:       PetscCall(SVDErrorView_DETAIL(svd,etype,viewer));
342:       break;
343:     case PETSC_VIEWER_ASCII_MATLAB:
344:       PetscCall(SVDErrorView_MATLAB(svd,etype,viewer));
345:       break;
346:     default:
347:       PetscCall(PetscInfo(svd,"Unsupported viewer format %s\n",PetscViewerFormats[format]));
348:   }
349:   PetscFunctionReturn(PETSC_SUCCESS);
350: }

352: /*@
353:    SVDErrorViewFromOptions - Processes command line options to determine if/how
354:    the errors of the computed solution are to be viewed.

356:    Collective

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

361:    Level: developer

363: .seealso: [](ch:svd), `SVDErrorView()`
364: @*/
365: PetscErrorCode SVDErrorViewFromOptions(SVD svd)
366: {
367:   PetscViewer       viewer;
368:   PetscBool         flg;
369:   static PetscBool  incall = PETSC_FALSE;
370:   PetscViewerFormat format;

372:   PetscFunctionBegin;
373:   if (incall) PetscFunctionReturn(PETSC_SUCCESS);
374:   incall = PETSC_TRUE;
375:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,"-svd_error_absolute",&viewer,&format,&flg));
376:   if (flg) {
377:     PetscCall(PetscViewerPushFormat(viewer,format));
378:     PetscCall(SVDErrorView(svd,SVD_ERROR_ABSOLUTE,viewer));
379:     PetscCall(PetscViewerPopFormat(viewer));
380:     PetscCall(PetscViewerDestroy(&viewer));
381:   }
382:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,"-svd_error_relative",&viewer,&format,&flg));
383:   if (flg) {
384:     PetscCall(PetscViewerPushFormat(viewer,format));
385:     PetscCall(SVDErrorView(svd,SVD_ERROR_RELATIVE,viewer));
386:     PetscCall(PetscViewerPopFormat(viewer));
387:     PetscCall(PetscViewerDestroy(&viewer));
388:   }
389:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,"-svd_error_norm",&viewer,&format,&flg));
390:   if (flg) {
391:     PetscCall(PetscViewerPushFormat(viewer,format));
392:     PetscCall(SVDErrorView(svd,SVD_ERROR_NORM,viewer));
393:     PetscCall(PetscViewerPopFormat(viewer));
394:     PetscCall(PetscViewerDestroy(&viewer));
395:   }
396:   incall = PETSC_FALSE;
397:   PetscFunctionReturn(PETSC_SUCCESS);
398: }

400: static PetscErrorCode SVDValuesView_DRAW(SVD svd,PetscViewer viewer)
401: {
402:   PetscDraw      draw;
403:   PetscDrawSP    drawsp;
404:   PetscReal      re,im=0.0;
405:   PetscInt       i;

407:   PetscFunctionBegin;
408:   if (!svd->nconv) PetscFunctionReturn(PETSC_SUCCESS);
409:   PetscCall(PetscViewerDrawGetDraw(viewer,0,&draw));
410:   PetscCall(PetscDrawSetTitle(draw,"Computed singular values"));
411:   PetscCall(PetscDrawSPCreate(draw,1,&drawsp));
412:   for (i=0;i<svd->nconv;i++) {
413:     re = svd->sigma[svd->perm[i]];
414:     PetscCall(PetscDrawSPAddPoint(drawsp,&re,&im));
415:   }
416:   PetscCall(PetscDrawSPDraw(drawsp,PETSC_TRUE));
417:   PetscCall(PetscDrawSPSave(drawsp));
418:   PetscCall(PetscDrawSPDestroy(&drawsp));
419:   PetscFunctionReturn(PETSC_SUCCESS);
420: }

422: static PetscErrorCode SVDValuesView_BINARY(SVD svd,PetscViewer viewer)
423: {
424:   PetscInt       i,k;
425:   PetscReal      *sv;

427:   PetscFunctionBegin;
428:   PetscCall(PetscMalloc1(svd->nconv,&sv));
429:   for (i=0;i<svd->nconv;i++) {
430:     k = svd->perm[i];
431:     sv[i] = svd->sigma[k];
432:   }
433:   PetscCall(PetscViewerBinaryWrite(viewer,sv,svd->nconv,PETSC_REAL));
434:   PetscCall(PetscFree(sv));
435:   PetscFunctionReturn(PETSC_SUCCESS);
436: }

438: #if defined(PETSC_HAVE_HDF5)
439: static PetscErrorCode SVDValuesView_HDF5(SVD svd,PetscViewer viewer)
440: {
441:   PetscInt       i,k,n,N;
442:   PetscMPIInt    rank;
443:   Vec            v;
444:   char           vname[30];
445:   const char     *ename;

447:   PetscFunctionBegin;
448:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)svd),&rank));
449:   N = svd->nconv;
450:   n = rank? 0: N;
451:   /* create a vector containing the singular values */
452:   PetscCall(VecCreateMPI(PetscObjectComm((PetscObject)svd),n,N,&v));
453:   PetscCall(PetscObjectGetName((PetscObject)svd,&ename));
454:   PetscCall(PetscSNPrintf(vname,sizeof(vname),"sigma_%s",ename));
455:   PetscCall(PetscObjectSetName((PetscObject)v,vname));
456:   if (!rank) {
457:     for (i=0;i<svd->nconv;i++) {
458:       k = svd->perm[i];
459:       PetscCall(VecSetValue(v,i,svd->sigma[k],INSERT_VALUES));
460:     }
461:   }
462:   PetscCall(VecAssemblyBegin(v));
463:   PetscCall(VecAssemblyEnd(v));
464:   PetscCall(VecView(v,viewer));
465:   PetscCall(VecDestroy(&v));
466:   PetscFunctionReturn(PETSC_SUCCESS);
467: }
468: #endif

470: static PetscErrorCode SVDValuesView_ASCII(SVD svd,PetscViewer viewer)
471: {
472:   PetscInt       i;

474:   PetscFunctionBegin;
475:   PetscCall(PetscViewerASCIIPrintf(viewer,"Singular values = \n"));
476:   for (i=0;i<svd->nconv;i++) PetscCall(PetscViewerASCIIPrintf(viewer,"   %.5f\n",(double)svd->sigma[svd->perm[i]]));
477:   PetscCall(PetscViewerASCIIPrintf(viewer,"\n"));
478:   PetscFunctionReturn(PETSC_SUCCESS);
479: }

481: static PetscErrorCode SVDValuesView_MATLAB(SVD svd,PetscViewer viewer)
482: {
483:   PetscInt       i;
484:   const char     *name;

486:   PetscFunctionBegin;
487:   PetscCall(PetscObjectGetName((PetscObject)svd,&name));
488:   PetscCall(PetscViewerASCIIPrintf(viewer,"Sigma_%s = [\n",name));
489:   for (i=0;i<svd->nconv;i++) PetscCall(PetscViewerASCIIPrintf(viewer,"%18.16e\n",(double)svd->sigma[svd->perm[i]]));
490:   PetscCall(PetscViewerASCIIPrintf(viewer,"];\n"));
491:   PetscFunctionReturn(PETSC_SUCCESS);
492: }

494: /*@
495:    SVDValuesView - Displays the computed singular values in a viewer.

497:    Collective

499:    Input Parameters:
500: +  svd    - the singular value solver context
501: -  viewer - the viewer

503:    Options Database Key:
504: .  -svd_view_values - print computed singular values

506:    Note:
507:    The command-line option listed above admits an optional argument
508:    specifying the viewer type and options. For instance, use
509:    `-svd_view_values :evals.m:ascii_matlab` to save the values in a file
510:    that can be executed in Matlab.

512:    Level: intermediate

514: .seealso: [](ch:svd), `SVDSolve()`, `SVDVectorsView()`, `SVDErrorView()`
515: @*/
516: PetscErrorCode SVDValuesView(SVD svd,PetscViewer viewer)
517: {
518:   PetscBool         isascii,isdraw,isbinary;
519:   PetscViewerFormat format;
520: #if defined(PETSC_HAVE_HDF5)
521:   PetscBool         ishdf5;
522: #endif

524:   PetscFunctionBegin;
526:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)svd),&viewer));
528:   PetscCheckSameComm(svd,1,viewer,2);
529:   SVDCheckSolved(svd,1);
530:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw));
531:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary));
532: #if defined(PETSC_HAVE_HDF5)
533:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERHDF5,&ishdf5));
534: #endif
535:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii));
536:   if (isdraw) PetscCall(SVDValuesView_DRAW(svd,viewer));
537:   else if (isbinary) PetscCall(SVDValuesView_BINARY(svd,viewer));
538: #if defined(PETSC_HAVE_HDF5)
539:   else if (ishdf5) PetscCall(SVDValuesView_HDF5(svd,viewer));
540: #endif
541:   else if (isascii) {
542:     PetscCall(PetscViewerGetFormat(viewer,&format));
543:     switch (format) {
544:       case PETSC_VIEWER_DEFAULT:
545:       case PETSC_VIEWER_ASCII_INFO:
546:       case PETSC_VIEWER_ASCII_INFO_DETAIL:
547:         PetscCall(SVDValuesView_ASCII(svd,viewer));
548:         break;
549:       case PETSC_VIEWER_ASCII_MATLAB:
550:         PetscCall(SVDValuesView_MATLAB(svd,viewer));
551:         break;
552:       default:
553:         PetscCall(PetscInfo(svd,"Unsupported viewer format %s\n",PetscViewerFormats[format]));
554:     }
555:   }
556:   PetscFunctionReturn(PETSC_SUCCESS);
557: }

559: /*@
560:    SVDValuesViewFromOptions - Processes command line options to determine if/how
561:    the computed singular values are to be viewed.

563:    Collective

565:    Input Parameter:
566: .  svd - the singular value solver context

568:    Level: developer

570: .seealso: [](ch:svd), `SVDValuesView()`
571: @*/
572: PetscErrorCode SVDValuesViewFromOptions(SVD svd)
573: {
574:   PetscViewer       viewer;
575:   PetscBool         flg;
576:   static PetscBool  incall = PETSC_FALSE;
577:   PetscViewerFormat format;

579:   PetscFunctionBegin;
580:   if (incall) PetscFunctionReturn(PETSC_SUCCESS);
581:   incall = PETSC_TRUE;
582:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,"-svd_view_values",&viewer,&format,&flg));
583:   if (flg) {
584:     PetscCall(PetscViewerPushFormat(viewer,format));
585:     PetscCall(SVDValuesView(svd,viewer));
586:     PetscCall(PetscViewerPopFormat(viewer));
587:     PetscCall(PetscViewerDestroy(&viewer));
588:   }
589:   incall = PETSC_FALSE;
590:   PetscFunctionReturn(PETSC_SUCCESS);
591: }

593: /*@
594:    SVDVectorsView - Outputs computed singular vectors to a viewer.

596:    Collective

598:    Input Parameters:
599: +  svd    - the singular value solver context
600: -  viewer - the viewer

602:    Options Database Key:
603: .  -svd_view_vectors - output singular vectors

605:    Notes:
606:    Right and left singular vectors are interleaved, that is, the vectors are
607:    output in the following order\: `V0, U0, V1, U1, V2, U2, ...`

609:    The command-line option listed above admits an optional argument
610:    specifying the viewer type and options. For instance, use
611:    `-svd_view_vectors binary:svecs.bin` to save the vectors in a binary file.

613:    Level: intermediate

615: .seealso: [](ch:svd), `SVDSolve()`, `SVDValuesView()`, `SVDErrorView()`
616: @*/
617: PetscErrorCode SVDVectorsView(SVD svd,PetscViewer viewer)
618: {
619:   PetscInt       i,k;
620:   Vec            x;
621:   char           vname[30];
622:   const char     *ename;

624:   PetscFunctionBegin;
626:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)svd),&viewer));
628:   PetscCheckSameComm(svd,1,viewer,2);
629:   SVDCheckSolved(svd,1);
630:   if (svd->nconv) {
631:     PetscCall(PetscObjectGetName((PetscObject)svd,&ename));
632:     PetscCall(SVDComputeVectors(svd));
633:     for (i=0;i<svd->nconv;i++) {
634:       k = svd->perm[i];
635:       PetscCall(PetscSNPrintf(vname,sizeof(vname),"V%" PetscInt_FMT "_%s",i,ename));
636:       PetscCall(BVGetColumn(svd->V,k,&x));
637:       PetscCall(PetscObjectSetName((PetscObject)x,vname));
638:       PetscCall(VecView(x,viewer));
639:       PetscCall(BVRestoreColumn(svd->V,k,&x));
640:       PetscCall(PetscSNPrintf(vname,sizeof(vname),"U%" PetscInt_FMT "_%s",i,ename));
641:       PetscCall(BVGetColumn(svd->U,k,&x));
642:       PetscCall(PetscObjectSetName((PetscObject)x,vname));
643:       PetscCall(VecView(x,viewer));
644:       PetscCall(BVRestoreColumn(svd->U,k,&x));
645:     }
646:   }
647:   PetscFunctionReturn(PETSC_SUCCESS);
648: }

650: /*@
651:    SVDVectorsViewFromOptions - Processes command line options to determine if/how
652:    the computed singular vectors are to be viewed.

654:    Collective

656:    Input Parameter:
657: .  svd - the singular value solver context

659:    Level: developer

661: .seealso: [](ch:svd), `SVDVectorsView()`
662: @*/
663: PetscErrorCode SVDVectorsViewFromOptions(SVD svd)
664: {
665:   PetscViewer       viewer;
666:   PetscBool         flg = PETSC_FALSE;
667:   static PetscBool  incall = PETSC_FALSE;
668:   PetscViewerFormat format;

670:   PetscFunctionBegin;
671:   if (incall) PetscFunctionReturn(PETSC_SUCCESS);
672:   incall = PETSC_TRUE;
673:   PetscCall(PetscOptionsCreateViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,"-svd_view_vectors",&viewer,&format,&flg));
674:   if (flg) {
675:     PetscCall(PetscViewerPushFormat(viewer,format));
676:     PetscCall(SVDVectorsView(svd,viewer));
677:     PetscCall(PetscViewerPopFormat(viewer));
678:     PetscCall(PetscViewerDestroy(&viewer));
679:   }
680:   incall = PETSC_FALSE;
681:   PetscFunctionReturn(PETSC_SUCCESS);
682: }