Actual source code: epsopts.c

slepc-3.17.0 2022-03-31
Report Typos and Errors
  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:    EPS routines related to options that can be set via the command-line
 12:    or procedurally.
 13: */

 15: #include <slepc/private/epsimpl.h>
 16: #include <petscdraw.h>

 18: /*@C
 19:    EPSMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type
 20:    indicated by the user.

 22:    Collective on eps

 24:    Input Parameters:
 25: +  eps      - the eigensolver context
 26: .  opt      - the command line option for this monitor
 27: .  name     - the monitor type one is seeking
 28: .  ctx      - an optional user context for the monitor, or NULL
 29: -  trackall - whether this monitor tracks all eigenvalues or not

 31:    Level: developer

 33: .seealso: EPSMonitorSet(), EPSSetTrackAll()
 34: @*/
 35: PetscErrorCode EPSMonitorSetFromOptions(EPS eps,const char opt[],const char name[],void *ctx,PetscBool trackall)
 36: {
 37:   PetscErrorCode       (*mfunc)(EPS,PetscInt,PetscInt,PetscScalar*,PetscScalar*,PetscReal*,PetscInt,void*);
 38:   PetscErrorCode       (*cfunc)(PetscViewer,PetscViewerFormat,void*,PetscViewerAndFormat**);
 39:   PetscErrorCode       (*dfunc)(PetscViewerAndFormat**);
 40:   PetscViewerAndFormat *vf;
 41:   PetscViewer          viewer;
 42:   PetscViewerFormat    format;
 43:   PetscViewerType      vtype;
 44:   char                 key[PETSC_MAX_PATH_LEN];
 45:   PetscBool            flg;

 47:   PetscOptionsGetViewer(PetscObjectComm((PetscObject)eps),((PetscObject)eps)->options,((PetscObject)eps)->prefix,opt,&viewer,&format,&flg);
 48:   if (!flg) PetscFunctionReturn(0);

 50:   PetscViewerGetType(viewer,&vtype);
 51:   SlepcMonitorMakeKey_Internal(name,vtype,format,key);
 52:   PetscFunctionListFind(EPSMonitorList,key,&mfunc);
 54:   PetscFunctionListFind(EPSMonitorCreateList,key,&cfunc);
 55:   PetscFunctionListFind(EPSMonitorDestroyList,key,&dfunc);
 56:   if (!cfunc) cfunc = PetscViewerAndFormatCreate_Internal;
 57:   if (!dfunc) dfunc = PetscViewerAndFormatDestroy;

 59:   (*cfunc)(viewer,format,ctx,&vf);
 60:   PetscObjectDereference((PetscObject)viewer);
 61:   EPSMonitorSet(eps,mfunc,vf,(PetscErrorCode(*)(void **))dfunc);
 62:   if (trackall) EPSSetTrackAll(eps,PETSC_TRUE);
 63:   PetscFunctionReturn(0);
 64: }

 66: /*@
 67:    EPSSetFromOptions - Sets EPS options from the options database.
 68:    This routine must be called before EPSSetUp() if the user is to be
 69:    allowed to set the solver type.

 71:    Collective on eps

 73:    Input Parameters:
 74: .  eps - the eigensolver context

 76:    Notes:
 77:    To see all options, run your program with the -help option.

 79:    Level: beginner

 81: .seealso: EPSSetOptionsPrefix()
 82: @*/
 83: PetscErrorCode EPSSetFromOptions(EPS eps)
 84: {
 86:   char           type[256];
 87:   PetscBool      set,flg,flg1,flg2,flg3,bval;
 88:   PetscReal      r,array[2]={0,0};
 89:   PetscScalar    s;
 90:   PetscInt       i,j,k;
 91:   EPSBalance     bal;

 94:   EPSRegisterAll();
 95:   ierr = PetscObjectOptionsBegin((PetscObject)eps);
 96:     PetscOptionsFList("-eps_type","Eigensolver method","EPSSetType",EPSList,(char*)(((PetscObject)eps)->type_name?((PetscObject)eps)->type_name:EPSKRYLOVSCHUR),type,sizeof(type),&flg);
 97:     if (flg) EPSSetType(eps,type);
 98:     else if (!((PetscObject)eps)->type_name) EPSSetType(eps,EPSKRYLOVSCHUR);

100:     PetscOptionsBoolGroupBegin("-eps_hermitian","Hermitian eigenvalue problem","EPSSetProblemType",&flg);
101:     if (flg) EPSSetProblemType(eps,EPS_HEP);
102:     PetscOptionsBoolGroup("-eps_gen_hermitian","Generalized Hermitian eigenvalue problem","EPSSetProblemType",&flg);
103:     if (flg) EPSSetProblemType(eps,EPS_GHEP);
104:     PetscOptionsBoolGroup("-eps_non_hermitian","Non-Hermitian eigenvalue problem","EPSSetProblemType",&flg);
105:     if (flg) EPSSetProblemType(eps,EPS_NHEP);
106:     PetscOptionsBoolGroup("-eps_gen_non_hermitian","Generalized non-Hermitian eigenvalue problem","EPSSetProblemType",&flg);
107:     if (flg) EPSSetProblemType(eps,EPS_GNHEP);
108:     PetscOptionsBoolGroup("-eps_pos_gen_non_hermitian","Generalized non-Hermitian eigenvalue problem with positive semi-definite B","EPSSetProblemType",&flg);
109:     if (flg) EPSSetProblemType(eps,EPS_PGNHEP);
110:     PetscOptionsBoolGroupEnd("-eps_gen_indefinite","Generalized Hermitian-indefinite eigenvalue problem","EPSSetProblemType",&flg);
111:     if (flg) EPSSetProblemType(eps,EPS_GHIEP);

113:     PetscOptionsBoolGroupBegin("-eps_ritz","Rayleigh-Ritz extraction","EPSSetExtraction",&flg);
114:     if (flg) EPSSetExtraction(eps,EPS_RITZ);
115:     PetscOptionsBoolGroup("-eps_harmonic","Harmonic Ritz extraction","EPSSetExtraction",&flg);
116:     if (flg) EPSSetExtraction(eps,EPS_HARMONIC);
117:     PetscOptionsBoolGroup("-eps_harmonic_relative","Relative harmonic Ritz extraction","EPSSetExtraction",&flg);
118:     if (flg) EPSSetExtraction(eps,EPS_HARMONIC_RELATIVE);
119:     PetscOptionsBoolGroup("-eps_harmonic_right","Right harmonic Ritz extraction","EPSSetExtraction",&flg);
120:     if (flg) EPSSetExtraction(eps,EPS_HARMONIC_RIGHT);
121:     PetscOptionsBoolGroup("-eps_harmonic_largest","Largest harmonic Ritz extraction","EPSSetExtraction",&flg);
122:     if (flg) EPSSetExtraction(eps,EPS_HARMONIC_LARGEST);
123:     PetscOptionsBoolGroup("-eps_refined","Refined Ritz extraction","EPSSetExtraction",&flg);
124:     if (flg) EPSSetExtraction(eps,EPS_REFINED);
125:     PetscOptionsBoolGroupEnd("-eps_refined_harmonic","Refined harmonic Ritz extraction","EPSSetExtraction",&flg);
126:     if (flg) EPSSetExtraction(eps,EPS_REFINED_HARMONIC);

128:     bal = eps->balance;
129:     PetscOptionsEnum("-eps_balance","Balancing method","EPSSetBalance",EPSBalanceTypes,(PetscEnum)bal,(PetscEnum*)&bal,&flg1);
130:     j = eps->balance_its;
131:     PetscOptionsInt("-eps_balance_its","Number of iterations in balancing","EPSSetBalance",eps->balance_its,&j,&flg2);
132:     r = eps->balance_cutoff;
133:     PetscOptionsReal("-eps_balance_cutoff","Cutoff value in balancing","EPSSetBalance",eps->balance_cutoff,&r,&flg3);
134:     if (flg1 || flg2 || flg3) EPSSetBalance(eps,bal,j,r);

136:     i = eps->max_it;
137:     PetscOptionsInt("-eps_max_it","Maximum number of iterations","EPSSetTolerances",eps->max_it,&i,&flg1);
138:     r = eps->tol;
139:     PetscOptionsReal("-eps_tol","Tolerance","EPSSetTolerances",SlepcDefaultTol(eps->tol),&r,&flg2);
140:     if (flg1 || flg2) EPSSetTolerances(eps,r,i);

142:     PetscOptionsBoolGroupBegin("-eps_conv_rel","Relative error convergence test","EPSSetConvergenceTest",&flg);
143:     if (flg) EPSSetConvergenceTest(eps,EPS_CONV_REL);
144:     PetscOptionsBoolGroup("-eps_conv_norm","Convergence test relative to the eigenvalue and the matrix norms","EPSSetConvergenceTest",&flg);
145:     if (flg) EPSSetConvergenceTest(eps,EPS_CONV_NORM);
146:     PetscOptionsBoolGroup("-eps_conv_abs","Absolute error convergence test","EPSSetConvergenceTest",&flg);
147:     if (flg) EPSSetConvergenceTest(eps,EPS_CONV_ABS);
148:     PetscOptionsBoolGroupEnd("-eps_conv_user","User-defined convergence test","EPSSetConvergenceTest",&flg);
149:     if (flg) EPSSetConvergenceTest(eps,EPS_CONV_USER);

151:     PetscOptionsBoolGroupBegin("-eps_stop_basic","Stop iteration if all eigenvalues converged or max_it reached","EPSSetStoppingTest",&flg);
152:     if (flg) EPSSetStoppingTest(eps,EPS_STOP_BASIC);
153:     PetscOptionsBoolGroupEnd("-eps_stop_user","User-defined stopping test","EPSSetStoppingTest",&flg);
154:     if (flg) EPSSetStoppingTest(eps,EPS_STOP_USER);

156:     i = eps->nev;
157:     PetscOptionsInt("-eps_nev","Number of eigenvalues to compute","EPSSetDimensions",eps->nev,&i,&flg1);
158:     j = eps->ncv;
159:     PetscOptionsInt("-eps_ncv","Number of basis vectors","EPSSetDimensions",eps->ncv,&j,&flg2);
160:     k = eps->mpd;
161:     PetscOptionsInt("-eps_mpd","Maximum dimension of projected problem","EPSSetDimensions",eps->mpd,&k,&flg3);
162:     if (flg1 || flg2 || flg3) EPSSetDimensions(eps,i,j,k);

164:     PetscOptionsBoolGroupBegin("-eps_largest_magnitude","Compute largest eigenvalues in magnitude","EPSSetWhichEigenpairs",&flg);
165:     if (flg) EPSSetWhichEigenpairs(eps,EPS_LARGEST_MAGNITUDE);
166:     PetscOptionsBoolGroup("-eps_smallest_magnitude","Compute smallest eigenvalues in magnitude","EPSSetWhichEigenpairs",&flg);
167:     if (flg) EPSSetWhichEigenpairs(eps,EPS_SMALLEST_MAGNITUDE);
168:     PetscOptionsBoolGroup("-eps_largest_real","Compute eigenvalues with largest real parts","EPSSetWhichEigenpairs",&flg);
169:     if (flg) EPSSetWhichEigenpairs(eps,EPS_LARGEST_REAL);
170:     PetscOptionsBoolGroup("-eps_smallest_real","Compute eigenvalues with smallest real parts","EPSSetWhichEigenpairs",&flg);
171:     if (flg) EPSSetWhichEigenpairs(eps,EPS_SMALLEST_REAL);
172:     PetscOptionsBoolGroup("-eps_largest_imaginary","Compute eigenvalues with largest imaginary parts","EPSSetWhichEigenpairs",&flg);
173:     if (flg) EPSSetWhichEigenpairs(eps,EPS_LARGEST_IMAGINARY);
174:     PetscOptionsBoolGroup("-eps_smallest_imaginary","Compute eigenvalues with smallest imaginary parts","EPSSetWhichEigenpairs",&flg);
175:     if (flg) EPSSetWhichEigenpairs(eps,EPS_SMALLEST_IMAGINARY);
176:     PetscOptionsBoolGroup("-eps_target_magnitude","Compute eigenvalues closest to target","EPSSetWhichEigenpairs",&flg);
177:     if (flg) EPSSetWhichEigenpairs(eps,EPS_TARGET_MAGNITUDE);
178:     PetscOptionsBoolGroup("-eps_target_real","Compute eigenvalues with real parts closest to target","EPSSetWhichEigenpairs",&flg);
179:     if (flg) EPSSetWhichEigenpairs(eps,EPS_TARGET_REAL);
180:     PetscOptionsBoolGroup("-eps_target_imaginary","Compute eigenvalues with imaginary parts closest to target","EPSSetWhichEigenpairs",&flg);
181:     if (flg) EPSSetWhichEigenpairs(eps,EPS_TARGET_IMAGINARY);
182:     PetscOptionsBoolGroupEnd("-eps_all","Compute all eigenvalues in an interval or a region","EPSSetWhichEigenpairs",&flg);
183:     if (flg) EPSSetWhichEigenpairs(eps,EPS_ALL);

185:     PetscOptionsScalar("-eps_target","Value of the target","EPSSetTarget",eps->target,&s,&flg);
186:     if (flg) {
187:       if (eps->which!=EPS_TARGET_REAL && eps->which!=EPS_TARGET_IMAGINARY) EPSSetWhichEigenpairs(eps,EPS_TARGET_MAGNITUDE);
188:       EPSSetTarget(eps,s);
189:     }

191:     k = 2;
192:     PetscOptionsRealArray("-eps_interval","Computational interval (two real values separated with a comma without spaces)","EPSSetInterval",array,&k,&flg);
193:     if (flg) {
195:       EPSSetWhichEigenpairs(eps,EPS_ALL);
196:       EPSSetInterval(eps,array[0],array[1]);
197:     }

199:     PetscOptionsBool("-eps_true_residual","Compute true residuals explicitly","EPSSetTrueResidual",eps->trueres,&eps->trueres,NULL);
200:     PetscOptionsBool("-eps_purify","Postprocess eigenvectors for purification","EPSSetPurify",eps->purify,&bval,&flg);
201:     if (flg) EPSSetPurify(eps,bval);
202:     PetscOptionsBool("-eps_two_sided","Use two-sided variant (to compute left eigenvectors)","EPSSetTwoSided",eps->twosided,&bval,&flg);
203:     if (flg) EPSSetTwoSided(eps,bval);

205:     /* -----------------------------------------------------------------------*/
206:     /*
207:       Cancels all monitors hardwired into code before call to EPSSetFromOptions()
208:     */
209:     PetscOptionsBool("-eps_monitor_cancel","Remove any hardwired monitor routines","EPSMonitorCancel",PETSC_FALSE,&flg,&set);
210:     if (set && flg) EPSMonitorCancel(eps);
211:     EPSMonitorSetFromOptions(eps,"-eps_monitor","first_approximation",NULL,PETSC_FALSE);
212:     EPSMonitorSetFromOptions(eps,"-eps_monitor_all","all_approximations",NULL,PETSC_TRUE);
213:     EPSMonitorSetFromOptions(eps,"-eps_monitor_conv","convergence_history",NULL,PETSC_FALSE);

215:     /* -----------------------------------------------------------------------*/
216:     PetscOptionsName("-eps_view","Print detailed information on solver used","EPSView",NULL);
217:     PetscOptionsName("-eps_view_vectors","View computed eigenvectors","EPSVectorsView",NULL);
218:     PetscOptionsName("-eps_view_values","View computed eigenvalues","EPSValuesView",NULL);
219:     PetscOptionsName("-eps_converged_reason","Print reason for convergence, and number of iterations","EPSConvergedReasonView",NULL);
220:     PetscOptionsName("-eps_error_absolute","Print absolute errors of each eigenpair","EPSErrorView",NULL);
221:     PetscOptionsName("-eps_error_relative","Print relative errors of each eigenpair","EPSErrorView",NULL);
222:     PetscOptionsName("-eps_error_backward","Print backward errors of each eigenpair","EPSErrorView",NULL);

224:     if (eps->ops->setfromoptions) (*eps->ops->setfromoptions)(PetscOptionsObject,eps);
225:     PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)eps);
226:   ierr = PetscOptionsEnd();

228:   if (!eps->V) EPSGetBV(eps,&eps->V);
229:   BVSetFromOptions(eps->V);
230:   if (!eps->rg) EPSGetRG(eps,&eps->rg);
231:   RGSetFromOptions(eps->rg);
232:   if (eps->useds) {
233:     if (!eps->ds) EPSGetDS(eps,&eps->ds);
234:     DSSetFromOptions(eps->ds);
235:   }
236:   if (!eps->st) EPSGetST(eps,&eps->st);
237:   EPSSetDefaultST(eps);
238:   STSetFromOptions(eps->st);
239:   PetscFunctionReturn(0);
240: }

242: /*@C
243:    EPSGetTolerances - Gets the tolerance and maximum iteration count used
244:    by the EPS convergence tests.

246:    Not Collective

248:    Input Parameter:
249: .  eps - the eigensolver context

251:    Output Parameters:
252: +  tol - the convergence tolerance
253: -  maxits - maximum number of iterations

255:    Notes:
256:    The user can specify NULL for any parameter that is not needed.

258:    Level: intermediate

260: .seealso: EPSSetTolerances()
261: @*/
262: PetscErrorCode EPSGetTolerances(EPS eps,PetscReal *tol,PetscInt *maxits)
263: {
265:   if (tol)    *tol    = eps->tol;
266:   if (maxits) *maxits = eps->max_it;
267:   PetscFunctionReturn(0);
268: }

270: /*@
271:    EPSSetTolerances - Sets the tolerance and maximum iteration count used
272:    by the EPS convergence tests.

274:    Logically Collective on eps

276:    Input Parameters:
277: +  eps - the eigensolver context
278: .  tol - the convergence tolerance
279: -  maxits - maximum number of iterations to use

281:    Options Database Keys:
282: +  -eps_tol <tol> - Sets the convergence tolerance
283: -  -eps_max_it <maxits> - Sets the maximum number of iterations allowed

285:    Notes:
286:    Use PETSC_DEFAULT for either argument to assign a reasonably good value.

288:    Level: intermediate

290: .seealso: EPSGetTolerances()
291: @*/
292: PetscErrorCode EPSSetTolerances(EPS eps,PetscReal tol,PetscInt maxits)
293: {
297:   if (tol == PETSC_DEFAULT) {
298:     eps->tol   = PETSC_DEFAULT;
299:     eps->state = EPS_STATE_INITIAL;
300:   } else {
302:     eps->tol = tol;
303:   }
304:   if (maxits == PETSC_DEFAULT || maxits == PETSC_DECIDE) {
305:     eps->max_it = PETSC_DEFAULT;
306:     eps->state  = EPS_STATE_INITIAL;
307:   } else {
309:     eps->max_it = maxits;
310:   }
311:   PetscFunctionReturn(0);
312: }

314: /*@C
315:    EPSGetDimensions - Gets the number of eigenvalues to compute
316:    and the dimension of the subspace.

318:    Not Collective

320:    Input Parameter:
321: .  eps - the eigensolver context

323:    Output Parameters:
324: +  nev - number of eigenvalues to compute
325: .  ncv - the maximum dimension of the subspace to be used by the solver
326: -  mpd - the maximum dimension allowed for the projected problem

328:    Level: intermediate

330: .seealso: EPSSetDimensions()
331: @*/
332: PetscErrorCode EPSGetDimensions(EPS eps,PetscInt *nev,PetscInt *ncv,PetscInt *mpd)
333: {
335:   if (nev) *nev = eps->nev;
336:   if (ncv) *ncv = eps->ncv;
337:   if (mpd) *mpd = eps->mpd;
338:   PetscFunctionReturn(0);
339: }

341: /*@
342:    EPSSetDimensions - Sets the number of eigenvalues to compute
343:    and the dimension of the subspace.

345:    Logically Collective on eps

347:    Input Parameters:
348: +  eps - the eigensolver context
349: .  nev - number of eigenvalues to compute
350: .  ncv - the maximum dimension of the subspace to be used by the solver
351: -  mpd - the maximum dimension allowed for the projected problem

353:    Options Database Keys:
354: +  -eps_nev <nev> - Sets the number of eigenvalues
355: .  -eps_ncv <ncv> - Sets the dimension of the subspace
356: -  -eps_mpd <mpd> - Sets the maximum projected dimension

358:    Notes:
359:    Use PETSC_DEFAULT for ncv and mpd to assign a reasonably good value, which is
360:    dependent on the solution method.

362:    The parameters ncv and mpd are intimately related, so that the user is advised
363:    to set one of them at most. Normal usage is that
364:    (a) in cases where nev is small, the user sets ncv (a reasonable default is 2*nev); and
365:    (b) in cases where nev is large, the user sets mpd.

367:    The value of ncv should always be between nev and (nev+mpd), typically
368:    ncv=nev+mpd. If nev is not too large, mpd=nev is a reasonable choice, otherwise
369:    a smaller value should be used.

371:    When computing all eigenvalues in an interval, see EPSSetInterval(), these
372:    parameters lose relevance, and tuning must be done with
373:    EPSKrylovSchurSetDimensions().

375:    Level: intermediate

377: .seealso: EPSGetDimensions(), EPSSetInterval(), EPSKrylovSchurSetDimensions()
378: @*/
379: PetscErrorCode EPSSetDimensions(EPS eps,PetscInt nev,PetscInt ncv,PetscInt mpd)
380: {
386:   eps->nev = nev;
387:   if (ncv == PETSC_DECIDE || ncv == PETSC_DEFAULT) {
388:     eps->ncv = PETSC_DEFAULT;
389:   } else {
391:     eps->ncv = ncv;
392:   }
393:   if (mpd == PETSC_DECIDE || mpd == PETSC_DEFAULT) {
394:     eps->mpd = PETSC_DEFAULT;
395:   } else {
397:     eps->mpd = mpd;
398:   }
399:   eps->state = EPS_STATE_INITIAL;
400:   PetscFunctionReturn(0);
401: }

403: /*@
404:    EPSSetWhichEigenpairs - Specifies which portion of the spectrum is
405:    to be sought.

407:    Logically Collective on eps

409:    Input Parameters:
410: +  eps   - eigensolver context obtained from EPSCreate()
411: -  which - the portion of the spectrum to be sought

413:    Possible values:
414:    The parameter 'which' can have one of these values

416: +     EPS_LARGEST_MAGNITUDE - largest eigenvalues in magnitude (default)
417: .     EPS_SMALLEST_MAGNITUDE - smallest eigenvalues in magnitude
418: .     EPS_LARGEST_REAL - largest real parts
419: .     EPS_SMALLEST_REAL - smallest real parts
420: .     EPS_LARGEST_IMAGINARY - largest imaginary parts
421: .     EPS_SMALLEST_IMAGINARY - smallest imaginary parts
422: .     EPS_TARGET_MAGNITUDE - eigenvalues closest to the target (in magnitude)
423: .     EPS_TARGET_REAL - eigenvalues with real part closest to target
424: .     EPS_TARGET_IMAGINARY - eigenvalues with imaginary part closest to target
425: .     EPS_ALL - all eigenvalues contained in a given interval or region
426: -     EPS_WHICH_USER - user defined ordering set with EPSSetEigenvalueComparison()

428:    Options Database Keys:
429: +   -eps_largest_magnitude - Sets largest eigenvalues in magnitude
430: .   -eps_smallest_magnitude - Sets smallest eigenvalues in magnitude
431: .   -eps_largest_real - Sets largest real parts
432: .   -eps_smallest_real - Sets smallest real parts
433: .   -eps_largest_imaginary - Sets largest imaginary parts
434: .   -eps_smallest_imaginary - Sets smallest imaginary parts
435: .   -eps_target_magnitude - Sets eigenvalues closest to target
436: .   -eps_target_real - Sets real parts closest to target
437: .   -eps_target_imaginary - Sets imaginary parts closest to target
438: -   -eps_all - Sets all eigenvalues in an interval or region

440:    Notes:
441:    Not all eigensolvers implemented in EPS account for all the possible values
442:    stated above. Also, some values make sense only for certain types of
443:    problems. If SLEPc is compiled for real numbers EPS_LARGEST_IMAGINARY
444:    and EPS_SMALLEST_IMAGINARY use the absolute value of the imaginary part
445:    for eigenvalue selection.

447:    The target is a scalar value provided with EPSSetTarget().

449:    The criterion EPS_TARGET_IMAGINARY is available only in case PETSc and
450:    SLEPc have been built with complex scalars.

452:    EPS_ALL is intended for use in combination with an interval (see
453:    EPSSetInterval()), when all eigenvalues within the interval are requested,
454:    or in the context of the CISS solver for computing all eigenvalues in a region.
455:    In those cases, the number of eigenvalues is unknown, so the nev parameter
456:    has a different sense, see EPSSetDimensions().

458:    Level: intermediate

460: .seealso: EPSGetWhichEigenpairs(), EPSSetTarget(), EPSSetInterval(),
461:           EPSSetDimensions(), EPSSetEigenvalueComparison(), EPSWhich
462: @*/
463: PetscErrorCode EPSSetWhichEigenpairs(EPS eps,EPSWhich which)
464: {
467:   switch (which) {
468:     case EPS_LARGEST_MAGNITUDE:
469:     case EPS_SMALLEST_MAGNITUDE:
470:     case EPS_LARGEST_REAL:
471:     case EPS_SMALLEST_REAL:
472:     case EPS_LARGEST_IMAGINARY:
473:     case EPS_SMALLEST_IMAGINARY:
474:     case EPS_TARGET_MAGNITUDE:
475:     case EPS_TARGET_REAL:
476: #if defined(PETSC_USE_COMPLEX)
477:     case EPS_TARGET_IMAGINARY:
478: #endif
479:     case EPS_ALL:
480:     case EPS_WHICH_USER:
481:       if (eps->which != which) {
482:         eps->state = EPS_STATE_INITIAL;
483:         eps->which = which;
484:       }
485:       break;
486: #if !defined(PETSC_USE_COMPLEX)
487:     case EPS_TARGET_IMAGINARY:
488:       SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_SUP,"EPS_TARGET_IMAGINARY can be used only with complex scalars");
489: #endif
490:     default:
491:       SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'which' value");
492:   }
493:   PetscFunctionReturn(0);
494: }

496: /*@
497:    EPSGetWhichEigenpairs - Returns which portion of the spectrum is to be
498:    sought.

500:    Not Collective

502:    Input Parameter:
503: .  eps - eigensolver context obtained from EPSCreate()

505:    Output Parameter:
506: .  which - the portion of the spectrum to be sought

508:    Notes:
509:    See EPSSetWhichEigenpairs() for possible values of 'which'.

511:    Level: intermediate

513: .seealso: EPSSetWhichEigenpairs(), EPSWhich
514: @*/
515: PetscErrorCode EPSGetWhichEigenpairs(EPS eps,EPSWhich *which)
516: {
519:   *which = eps->which;
520:   PetscFunctionReturn(0);
521: }

523: /*@C
524:    EPSSetEigenvalueComparison - Specifies the eigenvalue comparison function
525:    when EPSSetWhichEigenpairs() is set to EPS_WHICH_USER.

527:    Logically Collective on eps

529:    Input Parameters:
530: +  eps  - eigensolver context obtained from EPSCreate()
531: .  func - a pointer to the comparison function
532: -  ctx  - a context pointer (the last parameter to the comparison function)

534:    Calling Sequence of func:
535: $   func(PetscScalar ar,PetscScalar ai,PetscScalar br,PetscScalar bi,PetscInt *res,void *ctx)

537: +   ar     - real part of the 1st eigenvalue
538: .   ai     - imaginary part of the 1st eigenvalue
539: .   br     - real part of the 2nd eigenvalue
540: .   bi     - imaginary part of the 2nd eigenvalue
541: .   res    - result of comparison
542: -   ctx    - optional context, as set by EPSSetEigenvalueComparison()

544:    Note:
545:    The returning parameter 'res' can be
546: +  negative - if the 1st eigenvalue is preferred to the 2st one
547: .  zero     - if both eigenvalues are equally preferred
548: -  positive - if the 2st eigenvalue is preferred to the 1st one

550:    Level: advanced

552: .seealso: EPSSetWhichEigenpairs(), EPSWhich
553: @*/
554: PetscErrorCode EPSSetEigenvalueComparison(EPS eps,PetscErrorCode (*func)(PetscScalar,PetscScalar,PetscScalar,PetscScalar,PetscInt*,void*),void* ctx)
555: {
557:   eps->sc->comparison    = func;
558:   eps->sc->comparisonctx = ctx;
559:   eps->which             = EPS_WHICH_USER;
560:   PetscFunctionReturn(0);
561: }

563: /*@C
564:    EPSSetArbitrarySelection - Specifies a function intended to look for
565:    eigenvalues according to an arbitrary selection criterion. This criterion
566:    can be based on a computation involving the current eigenvector approximation.

568:    Logically Collective on eps

570:    Input Parameters:
571: +  eps  - eigensolver context obtained from EPSCreate()
572: .  func - a pointer to the evaluation function
573: -  ctx  - a context pointer (the last parameter to the evaluation function)

575:    Calling Sequence of func:
576: $   func(PetscScalar er,PetscScalar ei,Vec xr,Vec xi,PetscScalar *rr,PetscScalar *ri,void *ctx)

578: +   er     - real part of the current eigenvalue approximation
579: .   ei     - imaginary part of the current eigenvalue approximation
580: .   xr     - real part of the current eigenvector approximation
581: .   xi     - imaginary part of the current eigenvector approximation
582: .   rr     - result of evaluation (real part)
583: .   ri     - result of evaluation (imaginary part)
584: -   ctx    - optional context, as set by EPSSetArbitrarySelection()

586:    Notes:
587:    This provides a mechanism to select eigenpairs by evaluating a user-defined
588:    function. When a function has been provided, the default selection based on
589:    sorting the eigenvalues is replaced by the sorting of the results of this
590:    function (with the same sorting criterion given in EPSSetWhichEigenpairs()).

592:    For instance, suppose you want to compute those eigenvectors that maximize
593:    a certain computable expression. Then implement the computation using
594:    the arguments xr and xi, and return the result in rr. Then set the standard
595:    sorting by magnitude so that the eigenpair with largest value of rr is
596:    selected.

598:    This evaluation function is collective, that is, all processes call it and
599:    it can use collective operations; furthermore, the computed result must
600:    be the same in all processes.

602:    The result of func is expressed as a complex number so that it is possible to
603:    use the standard eigenvalue sorting functions, but normally only rr is used.
604:    Set ri to zero unless it is meaningful in your application.

606:    Level: advanced

608: .seealso: EPSSetWhichEigenpairs()
609: @*/
610: PetscErrorCode EPSSetArbitrarySelection(EPS eps,PetscErrorCode (*func)(PetscScalar,PetscScalar,Vec,Vec,PetscScalar*,PetscScalar*,void*),void* ctx)
611: {
613:   eps->arbitrary    = func;
614:   eps->arbitraryctx = ctx;
615:   eps->state        = EPS_STATE_INITIAL;
616:   PetscFunctionReturn(0);
617: }

619: /*@C
620:    EPSSetConvergenceTestFunction - Sets a function to compute the error estimate
621:    used in the convergence test.

623:    Logically Collective on eps

625:    Input Parameters:
626: +  eps     - eigensolver context obtained from EPSCreate()
627: .  func    - a pointer to the convergence test function
628: .  ctx     - context for private data for the convergence routine (may be null)
629: -  destroy - a routine for destroying the context (may be null)

631:    Calling Sequence of func:
632: $   func(EPS eps,PetscScalar eigr,PetscScalar eigi,PetscReal res,PetscReal *errest,void *ctx)

634: +   eps    - eigensolver context obtained from EPSCreate()
635: .   eigr   - real part of the eigenvalue
636: .   eigi   - imaginary part of the eigenvalue
637: .   res    - residual norm associated to the eigenpair
638: .   errest - (output) computed error estimate
639: -   ctx    - optional context, as set by EPSSetConvergenceTestFunction()

641:    Note:
642:    If the error estimate returned by the convergence test function is less than
643:    the tolerance, then the eigenvalue is accepted as converged.

645:    Level: advanced

647: .seealso: EPSSetConvergenceTest(), EPSSetTolerances()
648: @*/
649: PetscErrorCode EPSSetConvergenceTestFunction(EPS eps,PetscErrorCode (*func)(EPS,PetscScalar,PetscScalar,PetscReal,PetscReal*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
650: {
652:   if (eps->convergeddestroy) (*eps->convergeddestroy)(eps->convergedctx);
653:   eps->convergeduser    = func;
654:   eps->convergeddestroy = destroy;
655:   eps->convergedctx     = ctx;
656:   if (func == EPSConvergedRelative) eps->conv = EPS_CONV_REL;
657:   else if (func == EPSConvergedNorm) eps->conv = EPS_CONV_NORM;
658:   else if (func == EPSConvergedAbsolute) eps->conv = EPS_CONV_ABS;
659:   else {
660:     eps->conv      = EPS_CONV_USER;
661:     eps->converged = eps->convergeduser;
662:   }
663:   PetscFunctionReturn(0);
664: }

666: /*@
667:    EPSSetConvergenceTest - Specifies how to compute the error estimate
668:    used in the convergence test.

670:    Logically Collective on eps

672:    Input Parameters:
673: +  eps  - eigensolver context obtained from EPSCreate()
674: -  conv - the type of convergence test

676:    Options Database Keys:
677: +  -eps_conv_abs  - Sets the absolute convergence test
678: .  -eps_conv_rel  - Sets the convergence test relative to the eigenvalue
679: .  -eps_conv_norm - Sets the convergence test relative to the matrix norms
680: -  -eps_conv_user - Selects the user-defined convergence test

682:    Note:
683:    The parameter 'conv' can have one of these values
684: +     EPS_CONV_ABS  - absolute error ||r||
685: .     EPS_CONV_REL  - error relative to the eigenvalue l, ||r||/|l|
686: .     EPS_CONV_NORM - error relative to the matrix norms, ||r||/(||A||+|l|*||B||)
687: -     EPS_CONV_USER - function set by EPSSetConvergenceTestFunction()

689:    Level: intermediate

691: .seealso: EPSGetConvergenceTest(), EPSSetConvergenceTestFunction(), EPSSetStoppingTest(), EPSConv
692: @*/
693: PetscErrorCode EPSSetConvergenceTest(EPS eps,EPSConv conv)
694: {
697:   switch (conv) {
698:     case EPS_CONV_ABS:  eps->converged = EPSConvergedAbsolute; break;
699:     case EPS_CONV_REL:  eps->converged = EPSConvergedRelative; break;
700:     case EPS_CONV_NORM: eps->converged = EPSConvergedNorm; break;
701:     case EPS_CONV_USER:
703:       eps->converged = eps->convergeduser;
704:       break;
705:     default:
706:       SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'conv' value");
707:   }
708:   eps->conv = conv;
709:   PetscFunctionReturn(0);
710: }

712: /*@
713:    EPSGetConvergenceTest - Gets the method used to compute the error estimate
714:    used in the convergence test.

716:    Not Collective

718:    Input Parameters:
719: .  eps   - eigensolver context obtained from EPSCreate()

721:    Output Parameters:
722: .  conv  - the type of convergence test

724:    Level: intermediate

726: .seealso: EPSSetConvergenceTest(), EPSConv
727: @*/
728: PetscErrorCode EPSGetConvergenceTest(EPS eps,EPSConv *conv)
729: {
732:   *conv = eps->conv;
733:   PetscFunctionReturn(0);
734: }

736: /*@C
737:    EPSSetStoppingTestFunction - Sets a function to decide when to stop the outer
738:    iteration of the eigensolver.

740:    Logically Collective on eps

742:    Input Parameters:
743: +  eps     - eigensolver context obtained from EPSCreate()
744: .  func    - pointer to the stopping test function
745: .  ctx     - context for private data for the stopping routine (may be null)
746: -  destroy - a routine for destroying the context (may be null)

748:    Calling Sequence of func:
749: $   func(EPS eps,PetscInt its,PetscInt max_it,PetscInt nconv,PetscInt nev,EPSConvergedReason *reason,void *ctx)

751: +   eps    - eigensolver context obtained from EPSCreate()
752: .   its    - current number of iterations
753: .   max_it - maximum number of iterations
754: .   nconv  - number of currently converged eigenpairs
755: .   nev    - number of requested eigenpairs
756: .   reason - (output) result of the stopping test
757: -   ctx    - optional context, as set by EPSSetStoppingTestFunction()

759:    Note:
760:    Normal usage is to first call the default routine EPSStoppingBasic() and then
761:    set reason to EPS_CONVERGED_USER if some user-defined conditions have been
762:    met. To let the eigensolver continue iterating, the result must be left as
763:    EPS_CONVERGED_ITERATING.

765:    Level: advanced

767: .seealso: EPSSetStoppingTest(), EPSStoppingBasic()
768: @*/
769: PetscErrorCode EPSSetStoppingTestFunction(EPS eps,PetscErrorCode (*func)(EPS,PetscInt,PetscInt,PetscInt,PetscInt,EPSConvergedReason*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
770: {
772:   if (eps->stoppingdestroy) (*eps->stoppingdestroy)(eps->stoppingctx);
773:   eps->stoppinguser    = func;
774:   eps->stoppingdestroy = destroy;
775:   eps->stoppingctx     = ctx;
776:   if (func == EPSStoppingBasic) eps->stop = EPS_STOP_BASIC;
777:   else {
778:     eps->stop     = EPS_STOP_USER;
779:     eps->stopping = eps->stoppinguser;
780:   }
781:   PetscFunctionReturn(0);
782: }

784: /*@
785:    EPSSetStoppingTest - Specifies how to decide the termination of the outer
786:    loop of the eigensolver.

788:    Logically Collective on eps

790:    Input Parameters:
791: +  eps  - eigensolver context obtained from EPSCreate()
792: -  stop - the type of stopping test

794:    Options Database Keys:
795: +  -eps_stop_basic - Sets the default stopping test
796: -  -eps_stop_user  - Selects the user-defined stopping test

798:    Note:
799:    The parameter 'stop' can have one of these values
800: +     EPS_STOP_BASIC - default stopping test
801: -     EPS_STOP_USER  - function set by EPSSetStoppingTestFunction()

803:    Level: advanced

805: .seealso: EPSGetStoppingTest(), EPSSetStoppingTestFunction(), EPSSetConvergenceTest(), EPSStop
806: @*/
807: PetscErrorCode EPSSetStoppingTest(EPS eps,EPSStop stop)
808: {
811:   switch (stop) {
812:     case EPS_STOP_BASIC: eps->stopping = EPSStoppingBasic; break;
813:     case EPS_STOP_USER:
815:       eps->stopping = eps->stoppinguser;
816:       break;
817:     default:
818:       SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'stop' value");
819:   }
820:   eps->stop = stop;
821:   PetscFunctionReturn(0);
822: }

824: /*@
825:    EPSGetStoppingTest - Gets the method used to decide the termination of the outer
826:    loop of the eigensolver.

828:    Not Collective

830:    Input Parameters:
831: .  eps   - eigensolver context obtained from EPSCreate()

833:    Output Parameters:
834: .  stop  - the type of stopping test

836:    Level: advanced

838: .seealso: EPSSetStoppingTest(), EPSStop
839: @*/
840: PetscErrorCode EPSGetStoppingTest(EPS eps,EPSStop *stop)
841: {
844:   *stop = eps->stop;
845:   PetscFunctionReturn(0);
846: }

848: /*@
849:    EPSSetProblemType - Specifies the type of the eigenvalue problem.

851:    Logically Collective on eps

853:    Input Parameters:
854: +  eps      - the eigensolver context
855: -  type     - a known type of eigenvalue problem

857:    Options Database Keys:
858: +  -eps_hermitian - Hermitian eigenvalue problem
859: .  -eps_gen_hermitian - generalized Hermitian eigenvalue problem
860: .  -eps_non_hermitian - non-Hermitian eigenvalue problem
861: .  -eps_gen_non_hermitian - generalized non-Hermitian eigenvalue problem
862: .  -eps_pos_gen_non_hermitian - generalized non-Hermitian eigenvalue problem
863:    with positive semi-definite B
864: -  -eps_gen_indefinite - generalized Hermitian-indefinite eigenvalue problem

866:    Notes:
867:    Allowed values for the problem type are Hermitian (EPS_HEP), non-Hermitian
868:    (EPS_NHEP), generalized Hermitian (EPS_GHEP), generalized non-Hermitian
869:    (EPS_GNHEP), generalized non-Hermitian with positive semi-definite B
870:    (EPS_PGNHEP), and generalized Hermitian-indefinite (EPS_GHIEP).

872:    This function must be used to instruct SLEPc to exploit symmetry. If no
873:    problem type is specified, by default a non-Hermitian problem is assumed
874:    (either standard or generalized). If the user knows that the problem is
875:    Hermitian (i.e. A=A^H) or generalized Hermitian (i.e. A=A^H, B=B^H, and
876:    B positive definite) then it is recommended to set the problem type so
877:    that eigensolver can exploit these properties.

879:    Level: intermediate

881: .seealso: EPSSetOperators(), EPSSetType(), EPSGetProblemType(), EPSProblemType
882: @*/
883: PetscErrorCode EPSSetProblemType(EPS eps,EPSProblemType type)
884: {
887:   if (type == eps->problem_type) PetscFunctionReturn(0);
888:   switch (type) {
889:     case EPS_HEP:
890:       eps->isgeneralized = PETSC_FALSE;
891:       eps->ishermitian = PETSC_TRUE;
892:       eps->ispositive = PETSC_FALSE;
893:       break;
894:     case EPS_NHEP:
895:       eps->isgeneralized = PETSC_FALSE;
896:       eps->ishermitian = PETSC_FALSE;
897:       eps->ispositive = PETSC_FALSE;
898:       break;
899:     case EPS_GHEP:
900:       eps->isgeneralized = PETSC_TRUE;
901:       eps->ishermitian = PETSC_TRUE;
902:       eps->ispositive = PETSC_TRUE;
903:       break;
904:     case EPS_GNHEP:
905:       eps->isgeneralized = PETSC_TRUE;
906:       eps->ishermitian = PETSC_FALSE;
907:       eps->ispositive = PETSC_FALSE;
908:       break;
909:     case EPS_PGNHEP:
910:       eps->isgeneralized = PETSC_TRUE;
911:       eps->ishermitian = PETSC_FALSE;
912:       eps->ispositive = PETSC_TRUE;
913:       break;
914:     case EPS_GHIEP:
915:       eps->isgeneralized = PETSC_TRUE;
916:       eps->ishermitian = PETSC_TRUE;
917:       eps->ispositive = PETSC_FALSE;
918:       break;
919:     default:
920:       SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_WRONG,"Unknown eigenvalue problem type");
921:   }
922:   eps->problem_type = type;
923:   eps->state = EPS_STATE_INITIAL;
924:   PetscFunctionReturn(0);
925: }

927: /*@
928:    EPSGetProblemType - Gets the problem type from the EPS object.

930:    Not Collective

932:    Input Parameter:
933: .  eps - the eigensolver context

935:    Output Parameter:
936: .  type - the problem type

938:    Level: intermediate

940: .seealso: EPSSetProblemType(), EPSProblemType
941: @*/
942: PetscErrorCode EPSGetProblemType(EPS eps,EPSProblemType *type)
943: {
946:   *type = eps->problem_type;
947:   PetscFunctionReturn(0);
948: }

950: /*@
951:    EPSSetExtraction - Specifies the type of extraction technique to be employed
952:    by the eigensolver.

954:    Logically Collective on eps

956:    Input Parameters:
957: +  eps  - the eigensolver context
958: -  extr - a known type of extraction

960:    Options Database Keys:
961: +  -eps_ritz - Rayleigh-Ritz extraction
962: .  -eps_harmonic - harmonic Ritz extraction
963: .  -eps_harmonic_relative - harmonic Ritz extraction relative to the eigenvalue
964: .  -eps_harmonic_right - harmonic Ritz extraction for rightmost eigenvalues
965: .  -eps_harmonic_largest - harmonic Ritz extraction for largest magnitude
966:    (without target)
967: .  -eps_refined - refined Ritz extraction
968: -  -eps_refined_harmonic - refined harmonic Ritz extraction

970:    Notes:
971:    Not all eigensolvers support all types of extraction. See the SLEPc
972:    Users Manual for details.

974:    By default, a standard Rayleigh-Ritz extraction is used. Other extractions
975:    may be useful when computing interior eigenvalues.

977:    Harmonic-type extractions are used in combination with a 'target'.

979:    Level: advanced

981: .seealso: EPSSetTarget(), EPSGetExtraction(), EPSExtraction
982: @*/
983: PetscErrorCode EPSSetExtraction(EPS eps,EPSExtraction extr)
984: {
987:   eps->extraction = extr;
988:   PetscFunctionReturn(0);
989: }

991: /*@
992:    EPSGetExtraction - Gets the extraction type used by the EPS object.

994:    Not Collective

996:    Input Parameter:
997: .  eps - the eigensolver context

999:    Output Parameter:
1000: .  extr - name of extraction type

1002:    Level: advanced

1004: .seealso: EPSSetExtraction(), EPSExtraction
1005: @*/
1006: PetscErrorCode EPSGetExtraction(EPS eps,EPSExtraction *extr)
1007: {
1010:   *extr = eps->extraction;
1011:   PetscFunctionReturn(0);
1012: }

1014: /*@
1015:    EPSSetBalance - Specifies the balancing technique to be employed by the
1016:    eigensolver, and some parameters associated to it.

1018:    Logically Collective on eps

1020:    Input Parameters:
1021: +  eps    - the eigensolver context
1022: .  bal    - the balancing method, one of EPS_BALANCE_NONE, EPS_BALANCE_ONESIDE,
1023:             EPS_BALANCE_TWOSIDE, or EPS_BALANCE_USER
1024: .  its    - number of iterations of the balancing algorithm
1025: -  cutoff - cutoff value

1027:    Options Database Keys:
1028: +  -eps_balance <method> - the balancing method, where <method> is one of
1029:                            'none', 'oneside', 'twoside', or 'user'
1030: .  -eps_balance_its <its> - number of iterations
1031: -  -eps_balance_cutoff <cutoff> - cutoff value

1033:    Notes:
1034:    When balancing is enabled, the solver works implicitly with matrix DAD^-1,
1035:    where D is an appropriate diagonal matrix. This improves the accuracy of
1036:    the computed results in some cases. See the SLEPc Users Manual for details.

1038:    Balancing makes sense only for non-Hermitian problems when the required
1039:    precision is high (i.e. a small tolerance such as 1e-15).

1041:    By default, balancing is disabled. The two-sided method is much more
1042:    effective than the one-sided counterpart, but it requires the system
1043:    matrices to have the MatMultTranspose operation defined.

1045:    The parameter 'its' is the number of iterations performed by the method. The
1046:    cutoff value is used only in the two-side variant. Use PETSC_DEFAULT to assign
1047:    a reasonably good value.

1049:    User-defined balancing is allowed provided that the corresponding matrix
1050:    is set via STSetBalanceMatrix.

1052:    Level: intermediate

1054: .seealso: EPSGetBalance(), EPSBalance, STSetBalanceMatrix()
1055: @*/
1056: PetscErrorCode EPSSetBalance(EPS eps,EPSBalance bal,PetscInt its,PetscReal cutoff)
1057: {
1062:   switch (bal) {
1063:     case EPS_BALANCE_NONE:
1064:     case EPS_BALANCE_ONESIDE:
1065:     case EPS_BALANCE_TWOSIDE:
1066:     case EPS_BALANCE_USER:
1067:       if (eps->balance != bal) {
1068:         eps->state = EPS_STATE_INITIAL;
1069:         eps->balance = bal;
1070:       }
1071:       break;
1072:     default:
1073:       SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"Invalid value of argument 'bal'");
1074:   }
1075:   if (its==PETSC_DECIDE || its==PETSC_DEFAULT) eps->balance_its = 5;
1076:   else {
1078:     eps->balance_its = its;
1079:   }
1080:   if (cutoff==PETSC_DECIDE || cutoff==PETSC_DEFAULT) eps->balance_cutoff = 1e-8;
1081:   else {
1083:     eps->balance_cutoff = cutoff;
1084:   }
1085:   PetscFunctionReturn(0);
1086: }

1088: /*@C
1089:    EPSGetBalance - Gets the balancing type used by the EPS object, and the
1090:    associated parameters.

1092:    Not Collective

1094:    Input Parameter:
1095: .  eps - the eigensolver context

1097:    Output Parameters:
1098: +  bal    - the balancing method
1099: .  its    - number of iterations of the balancing algorithm
1100: -  cutoff - cutoff value

1102:    Level: intermediate

1104:    Note:
1105:    The user can specify NULL for any parameter that is not needed.

1107: .seealso: EPSSetBalance(), EPSBalance
1108: @*/
1109: PetscErrorCode EPSGetBalance(EPS eps,EPSBalance *bal,PetscInt *its,PetscReal *cutoff)
1110: {
1112:   if (bal)    *bal = eps->balance;
1113:   if (its)    *its = eps->balance_its;
1114:   if (cutoff) *cutoff = eps->balance_cutoff;
1115:   PetscFunctionReturn(0);
1116: }

1118: /*@
1119:    EPSSetTwoSided - Sets the solver to use a two-sided variant so that left
1120:    eigenvectors are also computed.

1122:    Logically Collective on eps

1124:    Input Parameters:
1125: +  eps      - the eigensolver context
1126: -  twosided - whether the two-sided variant is to be used or not

1128:    Options Database Keys:
1129: .  -eps_two_sided <boolean> - Sets/resets the twosided flag

1131:    Notes:
1132:    If the user sets twosided=PETSC_TRUE then the solver uses a variant of
1133:    the algorithm that computes both right and left eigenvectors. This is
1134:    usually much more costly. This option is not available in all solvers.

1136:    When using two-sided solvers, the problem matrices must have both the
1137:    MatMult and MatMultTranspose operations defined.

1139:    Level: advanced

1141: .seealso: EPSGetTwoSided(), EPSGetLeftEigenvector()
1142: @*/
1143: PetscErrorCode EPSSetTwoSided(EPS eps,PetscBool twosided)
1144: {
1147:   if (twosided!=eps->twosided) {
1148:     eps->twosided = twosided;
1149:     eps->state    = EPS_STATE_INITIAL;
1150:   }
1151:   PetscFunctionReturn(0);
1152: }

1154: /*@
1155:    EPSGetTwoSided - Returns the flag indicating whether a two-sided variant
1156:    of the algorithm is being used or not.

1158:    Not Collective

1160:    Input Parameter:
1161: .  eps - the eigensolver context

1163:    Output Parameter:
1164: .  twosided - the returned flag

1166:    Level: advanced

1168: .seealso: EPSSetTwoSided()
1169: @*/
1170: PetscErrorCode EPSGetTwoSided(EPS eps,PetscBool *twosided)
1171: {
1174:   *twosided = eps->twosided;
1175:   PetscFunctionReturn(0);
1176: }

1178: /*@
1179:    EPSSetTrueResidual - Specifies if the solver must compute the true residual
1180:    explicitly or not.

1182:    Logically Collective on eps

1184:    Input Parameters:
1185: +  eps     - the eigensolver context
1186: -  trueres - whether true residuals are required or not

1188:    Options Database Keys:
1189: .  -eps_true_residual <boolean> - Sets/resets the boolean flag 'trueres'

1191:    Notes:
1192:    If the user sets trueres=PETSC_TRUE then the solver explicitly computes
1193:    the true residual for each eigenpair approximation, and uses it for
1194:    convergence testing. Computing the residual is usually an expensive
1195:    operation. Some solvers (e.g., Krylov solvers) can avoid this computation
1196:    by using a cheap estimate of the residual norm, but this may sometimes
1197:    give inaccurate results (especially if a spectral transform is being
1198:    used). On the contrary, preconditioned eigensolvers (e.g., Davidson solvers)
1199:    do rely on computing the true residual, so this option is irrelevant for them.

1201:    Level: advanced

1203: .seealso: EPSGetTrueResidual()
1204: @*/
1205: PetscErrorCode EPSSetTrueResidual(EPS eps,PetscBool trueres)
1206: {
1209:   eps->trueres = trueres;
1210:   PetscFunctionReturn(0);
1211: }

1213: /*@
1214:    EPSGetTrueResidual - Returns the flag indicating whether true
1215:    residuals must be computed explicitly or not.

1217:    Not Collective

1219:    Input Parameter:
1220: .  eps - the eigensolver context

1222:    Output Parameter:
1223: .  trueres - the returned flag

1225:    Level: advanced

1227: .seealso: EPSSetTrueResidual()
1228: @*/
1229: PetscErrorCode EPSGetTrueResidual(EPS eps,PetscBool *trueres)
1230: {
1233:   *trueres = eps->trueres;
1234:   PetscFunctionReturn(0);
1235: }

1237: /*@
1238:    EPSSetTrackAll - Specifies if the solver must compute the residual norm of all
1239:    approximate eigenpairs or not.

1241:    Logically Collective on eps

1243:    Input Parameters:
1244: +  eps      - the eigensolver context
1245: -  trackall - whether to compute all residuals or not

1247:    Notes:
1248:    If the user sets trackall=PETSC_TRUE then the solver computes (or estimates)
1249:    the residual norm for each eigenpair approximation. Computing the residual is
1250:    usually an expensive operation and solvers commonly compute only the residual
1251:    associated to the first unconverged eigenpair.

1253:    The option '-eps_monitor_all' automatically activates this option.

1255:    Level: developer

1257: .seealso: EPSGetTrackAll()
1258: @*/
1259: PetscErrorCode EPSSetTrackAll(EPS eps,PetscBool trackall)
1260: {
1263:   eps->trackall = trackall;
1264:   PetscFunctionReturn(0);
1265: }

1267: /*@
1268:    EPSGetTrackAll - Returns the flag indicating whether all residual norms must
1269:    be computed or not.

1271:    Not Collective

1273:    Input Parameter:
1274: .  eps - the eigensolver context

1276:    Output Parameter:
1277: .  trackall - the returned flag

1279:    Level: developer

1281: .seealso: EPSSetTrackAll()
1282: @*/
1283: PetscErrorCode EPSGetTrackAll(EPS eps,PetscBool *trackall)
1284: {
1287:   *trackall = eps->trackall;
1288:   PetscFunctionReturn(0);
1289: }

1291: /*@
1292:    EPSSetPurify - Deactivate eigenvector purification (which is activated by default).

1294:    Logically Collective on eps

1296:    Input Parameters:
1297: +  eps    - the eigensolver context
1298: -  purify - whether purification is required or not

1300:    Options Database Keys:
1301: .  -eps_purify <boolean> - Sets/resets the boolean flag 'purify'

1303:    Notes:
1304:    By default, eigenvectors of generalized symmetric eigenproblems are purified
1305:    in order to purge directions in the nullspace of matrix B. If the user knows
1306:    that B is non-singular, then purification can be safely deactivated and some
1307:    computational cost is avoided (this is particularly important in interval computations).

1309:    Level: intermediate

1311: .seealso: EPSGetPurify(), EPSSetInterval()
1312: @*/
1313: PetscErrorCode EPSSetPurify(EPS eps,PetscBool purify)
1314: {
1317:   if (purify!=eps->purify) {
1318:     eps->purify = purify;
1319:     eps->state  = EPS_STATE_INITIAL;
1320:   }
1321:   PetscFunctionReturn(0);
1322: }

1324: /*@
1325:    EPSGetPurify - Returns the flag indicating whether purification is activated
1326:    or not.

1328:    Not Collective

1330:    Input Parameter:
1331: .  eps - the eigensolver context

1333:    Output Parameter:
1334: .  purify - the returned flag

1336:    Level: intermediate

1338: .seealso: EPSSetPurify()
1339: @*/
1340: PetscErrorCode EPSGetPurify(EPS eps,PetscBool *purify)
1341: {
1344:   *purify = eps->purify;
1345:   PetscFunctionReturn(0);
1346: }

1348: /*@C
1349:    EPSSetOptionsPrefix - Sets the prefix used for searching for all
1350:    EPS options in the database.

1352:    Logically Collective on eps

1354:    Input Parameters:
1355: +  eps - the eigensolver context
1356: -  prefix - the prefix string to prepend to all EPS option requests

1358:    Notes:
1359:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1360:    The first character of all runtime options is AUTOMATICALLY the
1361:    hyphen.

1363:    For example, to distinguish between the runtime options for two
1364:    different EPS contexts, one could call
1365: .vb
1366:       EPSSetOptionsPrefix(eps1,"eig1_")
1367:       EPSSetOptionsPrefix(eps2,"eig2_")
1368: .ve

1370:    Level: advanced

1372: .seealso: EPSAppendOptionsPrefix(), EPSGetOptionsPrefix()
1373: @*/
1374: PetscErrorCode EPSSetOptionsPrefix(EPS eps,const char *prefix)
1375: {
1377:   if (!eps->st) EPSGetST(eps,&eps->st);
1378:   STSetOptionsPrefix(eps->st,prefix);
1379:   if (!eps->V) EPSGetBV(eps,&eps->V);
1380:   BVSetOptionsPrefix(eps->V,prefix);
1381:   if (!eps->ds) EPSGetDS(eps,&eps->ds);
1382:   DSSetOptionsPrefix(eps->ds,prefix);
1383:   if (!eps->rg) EPSGetRG(eps,&eps->rg);
1384:   RGSetOptionsPrefix(eps->rg,prefix);
1385:   PetscObjectSetOptionsPrefix((PetscObject)eps,prefix);
1386:   PetscFunctionReturn(0);
1387: }

1389: /*@C
1390:    EPSAppendOptionsPrefix - Appends to the prefix used for searching for all
1391:    EPS options in the database.

1393:    Logically Collective on eps

1395:    Input Parameters:
1396: +  eps - the eigensolver context
1397: -  prefix - the prefix string to prepend to all EPS option requests

1399:    Notes:
1400:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1401:    The first character of all runtime options is AUTOMATICALLY the hyphen.

1403:    Level: advanced

1405: .seealso: EPSSetOptionsPrefix(), EPSGetOptionsPrefix()
1406: @*/
1407: PetscErrorCode EPSAppendOptionsPrefix(EPS eps,const char *prefix)
1408: {
1410:   if (!eps->st) EPSGetST(eps,&eps->st);
1411:   STAppendOptionsPrefix(eps->st,prefix);
1412:   if (!eps->V) EPSGetBV(eps,&eps->V);
1413:   BVAppendOptionsPrefix(eps->V,prefix);
1414:   if (!eps->ds) EPSGetDS(eps,&eps->ds);
1415:   DSAppendOptionsPrefix(eps->ds,prefix);
1416:   if (!eps->rg) EPSGetRG(eps,&eps->rg);
1417:   RGAppendOptionsPrefix(eps->rg,prefix);
1418:   PetscObjectAppendOptionsPrefix((PetscObject)eps,prefix);
1419:   PetscFunctionReturn(0);
1420: }

1422: /*@C
1423:    EPSGetOptionsPrefix - Gets the prefix used for searching for all
1424:    EPS options in the database.

1426:    Not Collective

1428:    Input Parameters:
1429: .  eps - the eigensolver context

1431:    Output Parameters:
1432: .  prefix - pointer to the prefix string used is returned

1434:    Note:
1435:    On the Fortran side, the user should pass in a string 'prefix' of
1436:    sufficient length to hold the prefix.

1438:    Level: advanced

1440: .seealso: EPSSetOptionsPrefix(), EPSAppendOptionsPrefix()
1441: @*/
1442: PetscErrorCode EPSGetOptionsPrefix(EPS eps,const char *prefix[])
1443: {
1446:   PetscObjectGetOptionsPrefix((PetscObject)eps,prefix);
1447:   PetscFunctionReturn(0);
1448: }