Actual source code: nepopts.c

slepc-3.18.3 2023-03-24
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain

  6:    This file is part of SLEPc.
  7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
  8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  9: */
 10: /*
 11:    NEP routines related to options that can be set via the command-line
 12:    or procedurally
 13: */

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

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

 22:    Collective on nep

 24:    Input Parameters:
 25: +  nep      - the nonlinear 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: NEPMonitorSet(), NEPSetTrackAll()
 34: @*/
 35: PetscErrorCode NEPMonitorSetFromOptions(NEP nep,const char opt[],const char name[],void *ctx,PetscBool trackall)
 36: {
 37:   PetscErrorCode       (*mfunc)(NEP,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)nep),((PetscObject)nep)->options,((PetscObject)nep)->prefix,opt,&viewer,&format,&flg);
 48:   if (!flg) return 0;

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

 59:   (*cfunc)(viewer,format,ctx,&vf);
 60:   PetscObjectDereference((PetscObject)viewer);
 61:   NEPMonitorSet(nep,mfunc,vf,(PetscErrorCode(*)(void **))dfunc);
 62:   if (trackall) NEPSetTrackAll(nep,PETSC_TRUE);
 63:   return 0;
 64: }

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

 71:    Collective on nep

 73:    Input Parameters:
 74: .  nep - the nonlinear eigensolver context

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

 79:    Level: beginner

 81: .seealso: NEPSetOptionsPrefix()
 82: @*/
 83: PetscErrorCode NEPSetFromOptions(NEP nep)
 84: {
 85:   char            type[256];
 86:   PetscBool       set,flg,flg1,flg2,flg3,flg4,flg5,bval;
 87:   PetscReal       r;
 88:   PetscScalar     s;
 89:   PetscInt        i,j,k;
 90:   NEPRefine       refine;
 91:   NEPRefineScheme scheme;

 94:   NEPRegisterAll();
 95:   PetscObjectOptionsBegin((PetscObject)nep);
 96:     PetscOptionsFList("-nep_type","Nonlinear eigensolver method","NEPSetType",NEPList,(char*)(((PetscObject)nep)->type_name?((PetscObject)nep)->type_name:NEPRII),type,sizeof(type),&flg);
 97:     if (flg) NEPSetType(nep,type);
 98:     else if (!((PetscObject)nep)->type_name) NEPSetType(nep,NEPRII);

100:     PetscOptionsBoolGroupBegin("-nep_general","General nonlinear eigenvalue problem","NEPSetProblemType",&flg);
101:     if (flg) NEPSetProblemType(nep,NEP_GENERAL);
102:     PetscOptionsBoolGroupEnd("-nep_rational","Rational eigenvalue problem","NEPSetProblemType",&flg);
103:     if (flg) NEPSetProblemType(nep,NEP_RATIONAL);

105:     refine = nep->refine;
106:     PetscOptionsEnum("-nep_refine","Iterative refinement method","NEPSetRefine",NEPRefineTypes,(PetscEnum)refine,(PetscEnum*)&refine,&flg1);
107:     i = nep->npart;
108:     PetscOptionsInt("-nep_refine_partitions","Number of partitions of the communicator for iterative refinement","NEPSetRefine",nep->npart,&i,&flg2);
109:     r = nep->rtol;
110:     PetscOptionsReal("-nep_refine_tol","Tolerance for iterative refinement","NEPSetRefine",nep->rtol==PETSC_DEFAULT?SLEPC_DEFAULT_TOL/1000:nep->rtol,&r,&flg3);
111:     j = nep->rits;
112:     PetscOptionsInt("-nep_refine_its","Maximum number of iterations for iterative refinement","NEPSetRefine",nep->rits,&j,&flg4);
113:     scheme = nep->scheme;
114:     PetscOptionsEnum("-nep_refine_scheme","Scheme used for linear systems within iterative refinement","NEPSetRefine",NEPRefineSchemes,(PetscEnum)scheme,(PetscEnum*)&scheme,&flg5);
115:     if (flg1 || flg2 || flg3 || flg4 || flg5) NEPSetRefine(nep,refine,i,r,j,scheme);

117:     i = nep->max_it;
118:     PetscOptionsInt("-nep_max_it","Maximum number of iterations","NEPSetTolerances",nep->max_it,&i,&flg1);
119:     r = nep->tol;
120:     PetscOptionsReal("-nep_tol","Tolerance","NEPSetTolerances",SlepcDefaultTol(nep->tol),&r,&flg2);
121:     if (flg1 || flg2) NEPSetTolerances(nep,r,i);

123:     PetscOptionsBoolGroupBegin("-nep_conv_rel","Relative error convergence test","NEPSetConvergenceTest",&flg);
124:     if (flg) NEPSetConvergenceTest(nep,NEP_CONV_REL);
125:     PetscOptionsBoolGroup("-nep_conv_norm","Convergence test relative to the matrix norms","NEPSetConvergenceTest",&flg);
126:     if (flg) NEPSetConvergenceTest(nep,NEP_CONV_NORM);
127:     PetscOptionsBoolGroup("-nep_conv_abs","Absolute error convergence test","NEPSetConvergenceTest",&flg);
128:     if (flg) NEPSetConvergenceTest(nep,NEP_CONV_ABS);
129:     PetscOptionsBoolGroupEnd("-nep_conv_user","User-defined convergence test","NEPSetConvergenceTest",&flg);
130:     if (flg) NEPSetConvergenceTest(nep,NEP_CONV_USER);

132:     PetscOptionsBoolGroupBegin("-nep_stop_basic","Stop iteration if all eigenvalues converged or max_it reached","NEPSetStoppingTest",&flg);
133:     if (flg) NEPSetStoppingTest(nep,NEP_STOP_BASIC);
134:     PetscOptionsBoolGroupEnd("-nep_stop_user","User-defined stopping test","NEPSetStoppingTest",&flg);
135:     if (flg) NEPSetStoppingTest(nep,NEP_STOP_USER);

137:     i = nep->nev;
138:     PetscOptionsInt("-nep_nev","Number of eigenvalues to compute","NEPSetDimensions",nep->nev,&i,&flg1);
139:     j = nep->ncv;
140:     PetscOptionsInt("-nep_ncv","Number of basis vectors","NEPSetDimensions",nep->ncv,&j,&flg2);
141:     k = nep->mpd;
142:     PetscOptionsInt("-nep_mpd","Maximum dimension of projected problem","NEPSetDimensions",nep->mpd,&k,&flg3);
143:     if (flg1 || flg2 || flg3) NEPSetDimensions(nep,i,j,k);

145:     PetscOptionsBoolGroupBegin("-nep_largest_magnitude","Compute largest eigenvalues in magnitude","NEPSetWhichEigenpairs",&flg);
146:     if (flg) NEPSetWhichEigenpairs(nep,NEP_LARGEST_MAGNITUDE);
147:     PetscOptionsBoolGroup("-nep_smallest_magnitude","Compute smallest eigenvalues in magnitude","NEPSetWhichEigenpairs",&flg);
148:     if (flg) NEPSetWhichEigenpairs(nep,NEP_SMALLEST_MAGNITUDE);
149:     PetscOptionsBoolGroup("-nep_largest_real","Compute eigenvalues with largest real parts","NEPSetWhichEigenpairs",&flg);
150:     if (flg) NEPSetWhichEigenpairs(nep,NEP_LARGEST_REAL);
151:     PetscOptionsBoolGroup("-nep_smallest_real","Compute eigenvalues with smallest real parts","NEPSetWhichEigenpairs",&flg);
152:     if (flg) NEPSetWhichEigenpairs(nep,NEP_SMALLEST_REAL);
153:     PetscOptionsBoolGroup("-nep_largest_imaginary","Compute eigenvalues with largest imaginary parts","NEPSetWhichEigenpairs",&flg);
154:     if (flg) NEPSetWhichEigenpairs(nep,NEP_LARGEST_IMAGINARY);
155:     PetscOptionsBoolGroup("-nep_smallest_imaginary","Compute eigenvalues with smallest imaginary parts","NEPSetWhichEigenpairs",&flg);
156:     if (flg) NEPSetWhichEigenpairs(nep,NEP_SMALLEST_IMAGINARY);
157:     PetscOptionsBoolGroup("-nep_target_magnitude","Compute eigenvalues closest to target","NEPSetWhichEigenpairs",&flg);
158:     if (flg) NEPSetWhichEigenpairs(nep,NEP_TARGET_MAGNITUDE);
159:     PetscOptionsBoolGroup("-nep_target_real","Compute eigenvalues with real parts closest to target","NEPSetWhichEigenpairs",&flg);
160:     if (flg) NEPSetWhichEigenpairs(nep,NEP_TARGET_REAL);
161:     PetscOptionsBoolGroup("-nep_target_imaginary","Compute eigenvalues with imaginary parts closest to target","NEPSetWhichEigenpairs",&flg);
162:     if (flg) NEPSetWhichEigenpairs(nep,NEP_TARGET_IMAGINARY);
163:     PetscOptionsBoolGroupEnd("-nep_all","Compute all eigenvalues in a region","NEPSetWhichEigenpairs",&flg);
164:     if (flg) NEPSetWhichEigenpairs(nep,NEP_ALL);

166:     PetscOptionsScalar("-nep_target","Value of the target","NEPSetTarget",nep->target,&s,&flg);
167:     if (flg) {
168:       if (nep->which!=NEP_TARGET_REAL && nep->which!=NEP_TARGET_IMAGINARY) NEPSetWhichEigenpairs(nep,NEP_TARGET_MAGNITUDE);
169:       NEPSetTarget(nep,s);
170:     }

172:     PetscOptionsBool("-nep_two_sided","Use two-sided variant (to compute left eigenvectors)","NEPSetTwoSided",nep->twosided,&bval,&flg);
173:     if (flg) NEPSetTwoSided(nep,bval);

175:     /* -----------------------------------------------------------------------*/
176:     /*
177:       Cancels all monitors hardwired into code before call to NEPSetFromOptions()
178:     */
179:     PetscOptionsBool("-nep_monitor_cancel","Remove any hardwired monitor routines","NEPMonitorCancel",PETSC_FALSE,&flg,&set);
180:     if (set && flg) NEPMonitorCancel(nep);
181:     NEPMonitorSetFromOptions(nep,"-nep_monitor","first_approximation",NULL,PETSC_FALSE);
182:     NEPMonitorSetFromOptions(nep,"-nep_monitor_all","all_approximations",NULL,PETSC_TRUE);
183:     NEPMonitorSetFromOptions(nep,"-nep_monitor_conv","convergence_history",NULL,PETSC_FALSE);

185:     /* -----------------------------------------------------------------------*/
186:     PetscOptionsName("-nep_view","Print detailed information on solver used","NEPView",NULL);
187:     PetscOptionsName("-nep_view_vectors","View computed eigenvectors","NEPVectorsView",NULL);
188:     PetscOptionsName("-nep_view_values","View computed eigenvalues","NEPValuesView",NULL);
189:     PetscOptionsName("-nep_converged_reason","Print reason for convergence, and number of iterations","NEPConvergedReasonView",NULL);
190:     PetscOptionsName("-nep_error_absolute","Print absolute errors of each eigenpair","NEPErrorView",NULL);
191:     PetscOptionsName("-nep_error_relative","Print relative errors of each eigenpair","NEPErrorView",NULL);

193:     PetscTryTypeMethod(nep,setfromoptions,PetscOptionsObject);
194:     PetscObjectProcessOptionsHandlers((PetscObject)nep,PetscOptionsObject);
195:   PetscOptionsEnd();

197:   if (!nep->V) NEPGetBV(nep,&nep->V);
198:   BVSetFromOptions(nep->V);
199:   if (!nep->rg) NEPGetRG(nep,&nep->rg);
200:   RGSetFromOptions(nep->rg);
201:   if (nep->useds) {
202:     if (!nep->ds) NEPGetDS(nep,&nep->ds);
203:     DSSetFromOptions(nep->ds);
204:   }
205:   if (!nep->refineksp) NEPRefineGetKSP(nep,&nep->refineksp);
206:   KSPSetFromOptions(nep->refineksp);
207:   if (nep->fui==NEP_USER_INTERFACE_SPLIT) for (i=0;i<nep->nt;i++) FNSetFromOptions(nep->f[i]);
208:   return 0;
209: }

211: /*@C
212:    NEPGetTolerances - Gets the tolerance and maximum iteration count used
213:    by the NEP convergence tests.

215:    Not Collective

217:    Input Parameter:
218: .  nep - the nonlinear eigensolver context

220:    Output Parameters:
221: +  tol - the convergence tolerance
222: -  maxits - maximum number of iterations

224:    Notes:
225:    The user can specify NULL for any parameter that is not needed.

227:    Level: intermediate

229: .seealso: NEPSetTolerances()
230: @*/
231: PetscErrorCode NEPGetTolerances(NEP nep,PetscReal *tol,PetscInt *maxits)
232: {
234:   if (tol)    *tol    = nep->tol;
235:   if (maxits) *maxits = nep->max_it;
236:   return 0;
237: }

239: /*@
240:    NEPSetTolerances - Sets the tolerance and maximum iteration count used
241:    by the NEP convergence tests.

243:    Logically Collective on nep

245:    Input Parameters:
246: +  nep    - the nonlinear eigensolver context
247: .  tol    - the convergence tolerance
248: -  maxits - maximum number of iterations to use

250:    Options Database Keys:
251: +  -nep_tol <tol> - Sets the convergence tolerance
252: -  -nep_max_it <maxits> - Sets the maximum number of iterations allowed

254:    Notes:
255:    Use PETSC_DEFAULT for either argument to assign a reasonably good value.

257:    Level: intermediate

259: .seealso: NEPGetTolerances()
260: @*/
261: PetscErrorCode NEPSetTolerances(NEP nep,PetscReal tol,PetscInt maxits)
262: {
266:   if (tol == PETSC_DEFAULT) {
267:     nep->tol   = PETSC_DEFAULT;
268:     nep->state = NEP_STATE_INITIAL;
269:   } else {
271:     nep->tol = tol;
272:   }
273:   if (maxits == PETSC_DEFAULT || maxits == PETSC_DECIDE) {
274:     nep->max_it = PETSC_DEFAULT;
275:     nep->state  = NEP_STATE_INITIAL;
276:   } else {
278:     nep->max_it = maxits;
279:   }
280:   return 0;
281: }

283: /*@C
284:    NEPGetDimensions - Gets the number of eigenvalues to compute
285:    and the dimension of the subspace.

287:    Not Collective

289:    Input Parameter:
290: .  nep - the nonlinear eigensolver context

292:    Output Parameters:
293: +  nev - number of eigenvalues to compute
294: .  ncv - the maximum dimension of the subspace to be used by the solver
295: -  mpd - the maximum dimension allowed for the projected problem

297:    Notes:
298:    The user can specify NULL for any parameter that is not needed.

300:    Level: intermediate

302: .seealso: NEPSetDimensions()
303: @*/
304: PetscErrorCode NEPGetDimensions(NEP nep,PetscInt *nev,PetscInt *ncv,PetscInt *mpd)
305: {
307:   if (nev) *nev = nep->nev;
308:   if (ncv) *ncv = nep->ncv;
309:   if (mpd) *mpd = nep->mpd;
310:   return 0;
311: }

313: /*@
314:    NEPSetDimensions - Sets the number of eigenvalues to compute
315:    and the dimension of the subspace.

317:    Logically Collective on nep

319:    Input Parameters:
320: +  nep - the nonlinear eigensolver context
321: .  nev - number of eigenvalues to compute
322: .  ncv - the maximum dimension of the subspace to be used by the solver
323: -  mpd - the maximum dimension allowed for the projected problem

325:    Options Database Keys:
326: +  -nep_nev <nev> - Sets the number of eigenvalues
327: .  -nep_ncv <ncv> - Sets the dimension of the subspace
328: -  -nep_mpd <mpd> - Sets the maximum projected dimension

330:    Notes:
331:    Use PETSC_DEFAULT for ncv and mpd to assign a reasonably good value, which is
332:    dependent on the solution method.

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

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

343:    Level: intermediate

345: .seealso: NEPGetDimensions()
346: @*/
347: PetscErrorCode NEPSetDimensions(NEP nep,PetscInt nev,PetscInt ncv,PetscInt mpd)
348: {
354:   nep->nev = nev;
355:   if (ncv == PETSC_DECIDE || ncv == PETSC_DEFAULT) {
356:     nep->ncv = PETSC_DEFAULT;
357:   } else {
359:     nep->ncv = ncv;
360:   }
361:   if (mpd == PETSC_DECIDE || mpd == PETSC_DEFAULT) {
362:     nep->mpd = PETSC_DEFAULT;
363:   } else {
365:     nep->mpd = mpd;
366:   }
367:   nep->state = NEP_STATE_INITIAL;
368:   return 0;
369: }

371: /*@
372:     NEPSetWhichEigenpairs - Specifies which portion of the spectrum is
373:     to be sought.

375:     Logically Collective on nep

377:     Input Parameters:
378: +   nep   - eigensolver context obtained from NEPCreate()
379: -   which - the portion of the spectrum to be sought

381:     Possible values:
382:     The parameter 'which' can have one of these values

384: +     NEP_LARGEST_MAGNITUDE - largest eigenvalues in magnitude (default)
385: .     NEP_SMALLEST_MAGNITUDE - smallest eigenvalues in magnitude
386: .     NEP_LARGEST_REAL - largest real parts
387: .     NEP_SMALLEST_REAL - smallest real parts
388: .     NEP_LARGEST_IMAGINARY - largest imaginary parts
389: .     NEP_SMALLEST_IMAGINARY - smallest imaginary parts
390: .     NEP_TARGET_MAGNITUDE - eigenvalues closest to the target (in magnitude)
391: .     NEP_TARGET_REAL - eigenvalues with real part closest to target
392: .     NEP_TARGET_IMAGINARY - eigenvalues with imaginary part closest to target
393: .     NEP_ALL - all eigenvalues contained in a given region
394: -     NEP_WHICH_USER - user defined ordering set with NEPSetEigenvalueComparison()

396:     Options Database Keys:
397: +   -nep_largest_magnitude - Sets largest eigenvalues in magnitude
398: .   -nep_smallest_magnitude - Sets smallest eigenvalues in magnitude
399: .   -nep_largest_real - Sets largest real parts
400: .   -nep_smallest_real - Sets smallest real parts
401: .   -nep_largest_imaginary - Sets largest imaginary parts
402: .   -nep_smallest_imaginary - Sets smallest imaginary parts
403: .   -nep_target_magnitude - Sets eigenvalues closest to target
404: .   -nep_target_real - Sets real parts closest to target
405: .   -nep_target_imaginary - Sets imaginary parts closest to target
406: -   -nep_all - Sets all eigenvalues in a region

408:     Notes:
409:     Not all eigensolvers implemented in NEP account for all the possible values
410:     stated above. If SLEPc is compiled for real numbers NEP_LARGEST_IMAGINARY
411:     and NEP_SMALLEST_IMAGINARY use the absolute value of the imaginary part
412:     for eigenvalue selection.

414:     The target is a scalar value provided with NEPSetTarget().

416:     NEP_ALL is intended for use in the context of the CISS solver for
417:     computing all eigenvalues in a region.

419:     Level: intermediate

421: .seealso: NEPGetWhichEigenpairs(), NEPSetTarget(), NEPSetEigenvalueComparison(), NEPWhich
422: @*/
423: PetscErrorCode NEPSetWhichEigenpairs(NEP nep,NEPWhich which)
424: {
427:   switch (which) {
428:     case NEP_LARGEST_MAGNITUDE:
429:     case NEP_SMALLEST_MAGNITUDE:
430:     case NEP_LARGEST_REAL:
431:     case NEP_SMALLEST_REAL:
432:     case NEP_LARGEST_IMAGINARY:
433:     case NEP_SMALLEST_IMAGINARY:
434:     case NEP_TARGET_MAGNITUDE:
435:     case NEP_TARGET_REAL:
436: #if defined(PETSC_USE_COMPLEX)
437:     case NEP_TARGET_IMAGINARY:
438: #endif
439:     case NEP_ALL:
440:     case NEP_WHICH_USER:
441:       if (nep->which != which) {
442:         nep->state = NEP_STATE_INITIAL;
443:         nep->which = which;
444:       }
445:       break;
446: #if !defined(PETSC_USE_COMPLEX)
447:     case NEP_TARGET_IMAGINARY:
448:       SETERRQ(PetscObjectComm((PetscObject)nep),PETSC_ERR_SUP,"NEP_TARGET_IMAGINARY can be used only with complex scalars");
449: #endif
450:     default:
451:       SETERRQ(PetscObjectComm((PetscObject)nep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'which' value");
452:   }
453:   return 0;
454: }

456: /*@
457:     NEPGetWhichEigenpairs - Returns which portion of the spectrum is to be
458:     sought.

460:     Not Collective

462:     Input Parameter:
463: .   nep - eigensolver context obtained from NEPCreate()

465:     Output Parameter:
466: .   which - the portion of the spectrum to be sought

468:     Notes:
469:     See NEPSetWhichEigenpairs() for possible values of 'which'.

471:     Level: intermediate

473: .seealso: NEPSetWhichEigenpairs(), NEPWhich
474: @*/
475: PetscErrorCode NEPGetWhichEigenpairs(NEP nep,NEPWhich *which)
476: {
479:   *which = nep->which;
480:   return 0;
481: }

483: /*@C
484:    NEPSetEigenvalueComparison - Specifies the eigenvalue comparison function
485:    when NEPSetWhichEigenpairs() is set to NEP_WHICH_USER.

487:    Logically Collective on nep

489:    Input Parameters:
490: +  nep  - eigensolver context obtained from NEPCreate()
491: .  func - a pointer to the comparison function
492: -  ctx  - a context pointer (the last parameter to the comparison function)

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

497: +   ar     - real part of the 1st eigenvalue
498: .   ai     - imaginary part of the 1st eigenvalue
499: .   br     - real part of the 2nd eigenvalue
500: .   bi     - imaginary part of the 2nd eigenvalue
501: .   res    - result of comparison
502: -   ctx    - optional context, as set by NEPSetEigenvalueComparison()

504:    Note:
505:    The returning parameter 'res' can be
506: +  negative - if the 1st eigenvalue is preferred to the 2st one
507: .  zero     - if both eigenvalues are equally preferred
508: -  positive - if the 2st eigenvalue is preferred to the 1st one

510:    Level: advanced

512: .seealso: NEPSetWhichEigenpairs(), NEPWhich
513: @*/
514: PetscErrorCode NEPSetEigenvalueComparison(NEP nep,PetscErrorCode (*func)(PetscScalar,PetscScalar,PetscScalar,PetscScalar,PetscInt*,void*),void* ctx)
515: {
517:   nep->sc->comparison    = func;
518:   nep->sc->comparisonctx = ctx;
519:   nep->which             = NEP_WHICH_USER;
520:   return 0;
521: }

523: /*@
524:    NEPSetProblemType - Specifies the type of the nonlinear eigenvalue problem.

526:    Logically Collective on nep

528:    Input Parameters:
529: +  nep  - the nonlinear eigensolver context
530: -  type - a known type of nonlinear eigenvalue problem

532:    Options Database Keys:
533: +  -nep_general - general problem with no particular structure
534: -  -nep_rational - a rational eigenvalue problem defined in split form with all f_i rational

536:    Notes:
537:    Allowed values for the problem type are general (NEP_GENERAL), and rational
538:    (NEP_RATIONAL).

540:    This function is used to provide a hint to the NEP solver to exploit certain
541:    properties of the nonlinear eigenproblem. This hint may be used or not,
542:    depending on the solver. By default, no particular structure is assumed.

544:    Level: intermediate

546: .seealso: NEPSetType(), NEPGetProblemType(), NEPProblemType
547: @*/
548: PetscErrorCode NEPSetProblemType(NEP nep,NEPProblemType type)
549: {
553:   if (type != nep->problem_type) {
554:     nep->problem_type = type;
555:     nep->state = NEP_STATE_INITIAL;
556:   }
557:   return 0;
558: }

560: /*@
561:    NEPGetProblemType - Gets the problem type from the NEP object.

563:    Not Collective

565:    Input Parameter:
566: .  nep - the nonlinear eigensolver context

568:    Output Parameter:
569: .  type - the problem type

571:    Level: intermediate

573: .seealso: NEPSetProblemType(), NEPProblemType
574: @*/
575: PetscErrorCode NEPGetProblemType(NEP nep,NEPProblemType *type)
576: {
579:   *type = nep->problem_type;
580:   return 0;
581: }

583: /*@
584:    NEPSetTwoSided - Sets the solver to use a two-sided variant so that left
585:    eigenvectors are also computed.

587:    Logically Collective on nep

589:    Input Parameters:
590: +  nep      - the eigensolver context
591: -  twosided - whether the two-sided variant is to be used or not

593:    Options Database Keys:
594: .  -nep_two_sided <boolean> - Sets/resets the twosided flag

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

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

604:    Level: advanced

606: .seealso: NEPGetTwoSided(), NEPGetLeftEigenvector()
607: @*/
608: PetscErrorCode NEPSetTwoSided(NEP nep,PetscBool twosided)
609: {
612:   if (twosided!=nep->twosided) {
613:     nep->twosided = twosided;
614:     nep->state    = NEP_STATE_INITIAL;
615:   }
616:   return 0;
617: }

619: /*@
620:    NEPGetTwoSided - Returns the flag indicating whether a two-sided variant
621:    of the algorithm is being used or not.

623:    Not Collective

625:    Input Parameter:
626: .  nep - the eigensolver context

628:    Output Parameter:
629: .  twosided - the returned flag

631:    Level: advanced

633: .seealso: NEPSetTwoSided()
634: @*/
635: PetscErrorCode NEPGetTwoSided(NEP nep,PetscBool *twosided)
636: {
639:   *twosided = nep->twosided;
640:   return 0;
641: }

643: /*@C
644:    NEPSetConvergenceTestFunction - Sets a function to compute the error estimate
645:    used in the convergence test.

647:    Logically Collective on nep

649:    Input Parameters:
650: +  nep     - nonlinear eigensolver context obtained from NEPCreate()
651: .  func    - a pointer to the convergence test function
652: .  ctx     - context for private data for the convergence routine (may be null)
653: -  destroy - a routine for destroying the context (may be null)

655:    Calling Sequence of func:
656: $   func(NEP nep,PetscScalar eigr,PetscScalar eigi,PetscReal res,PetscReal *errest,void *ctx)

658: +   nep    - nonlinear eigensolver context obtained from NEPCreate()
659: .   eigr   - real part of the eigenvalue
660: .   eigi   - imaginary part of the eigenvalue
661: .   res    - residual norm associated to the eigenpair
662: .   errest - (output) computed error estimate
663: -   ctx    - optional context, as set by NEPSetConvergenceTestFunction()

665:    Note:
666:    If the error estimate returned by the convergence test function is less than
667:    the tolerance, then the eigenvalue is accepted as converged.

669:    Level: advanced

671: .seealso: NEPSetConvergenceTest(), NEPSetTolerances()
672: @*/
673: PetscErrorCode NEPSetConvergenceTestFunction(NEP nep,PetscErrorCode (*func)(NEP,PetscScalar,PetscScalar,PetscReal,PetscReal*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
674: {
676:   if (nep->convergeddestroy) (*nep->convergeddestroy)(nep->convergedctx);
677:   nep->convergeduser    = func;
678:   nep->convergeddestroy = destroy;
679:   nep->convergedctx     = ctx;
680:   if (func == NEPConvergedRelative) nep->conv = NEP_CONV_REL;
681:   else if (func == NEPConvergedNorm) nep->conv = NEP_CONV_NORM;
682:   else if (func == NEPConvergedAbsolute) nep->conv = NEP_CONV_ABS;
683:   else {
684:     nep->conv      = NEP_CONV_USER;
685:     nep->converged = nep->convergeduser;
686:   }
687:   return 0;
688: }

690: /*@
691:    NEPSetConvergenceTest - Specifies how to compute the error estimate
692:    used in the convergence test.

694:    Logically Collective on nep

696:    Input Parameters:
697: +  nep  - nonlinear eigensolver context obtained from NEPCreate()
698: -  conv - the type of convergence test

700:    Options Database Keys:
701: +  -nep_conv_abs  - Sets the absolute convergence test
702: .  -nep_conv_rel  - Sets the convergence test relative to the eigenvalue
703: -  -nep_conv_user - Selects the user-defined convergence test

705:    Note:
706:    The parameter 'conv' can have one of these values
707: +     NEP_CONV_ABS  - absolute error ||r||
708: .     NEP_CONV_REL  - error relative to the eigenvalue l, ||r||/|l|
709: .     NEP_CONV_NORM - error relative matrix norms, ||r||/sum_i(|f_i(l)|*||A_i||)
710: -     NEP_CONV_USER - function set by NEPSetConvergenceTestFunction()

712:    Level: intermediate

714: .seealso: NEPGetConvergenceTest(), NEPSetConvergenceTestFunction(), NEPSetStoppingTest(), NEPConv
715: @*/
716: PetscErrorCode NEPSetConvergenceTest(NEP nep,NEPConv conv)
717: {
720:   switch (conv) {
721:     case NEP_CONV_ABS:  nep->converged = NEPConvergedAbsolute; break;
722:     case NEP_CONV_REL:  nep->converged = NEPConvergedRelative; break;
723:     case NEP_CONV_NORM: nep->converged = NEPConvergedNorm; break;
724:     case NEP_CONV_USER:
726:       nep->converged = nep->convergeduser;
727:       break;
728:     default:
729:       SETERRQ(PetscObjectComm((PetscObject)nep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'conv' value");
730:   }
731:   nep->conv = conv;
732:   return 0;
733: }

735: /*@
736:    NEPGetConvergenceTest - Gets the method used to compute the error estimate
737:    used in the convergence test.

739:    Not Collective

741:    Input Parameters:
742: .  nep   - nonlinear eigensolver context obtained from NEPCreate()

744:    Output Parameters:
745: .  conv  - the type of convergence test

747:    Level: intermediate

749: .seealso: NEPSetConvergenceTest(), NEPConv
750: @*/
751: PetscErrorCode NEPGetConvergenceTest(NEP nep,NEPConv *conv)
752: {
755:   *conv = nep->conv;
756:   return 0;
757: }

759: /*@C
760:    NEPSetStoppingTestFunction - Sets a function to decide when to stop the outer
761:    iteration of the eigensolver.

763:    Logically Collective on nep

765:    Input Parameters:
766: +  nep     - nonlinear eigensolver context obtained from NEPCreate()
767: .  func    - pointer to the stopping test function
768: .  ctx     - context for private data for the stopping routine (may be null)
769: -  destroy - a routine for destroying the context (may be null)

771:    Calling Sequence of func:
772: $   func(NEP nep,PetscInt its,PetscInt max_it,PetscInt nconv,PetscInt nev,NEPConvergedReason *reason,void *ctx)

774: +   nep    - nonlinear eigensolver context obtained from NEPCreate()
775: .   its    - current number of iterations
776: .   max_it - maximum number of iterations
777: .   nconv  - number of currently converged eigenpairs
778: .   nev    - number of requested eigenpairs
779: .   reason - (output) result of the stopping test
780: -   ctx    - optional context, as set by NEPSetStoppingTestFunction()

782:    Note:
783:    Normal usage is to first call the default routine NEPStoppingBasic() and then
784:    set reason to NEP_CONVERGED_USER if some user-defined conditions have been
785:    met. To let the eigensolver continue iterating, the result must be left as
786:    NEP_CONVERGED_ITERATING.

788:    Level: advanced

790: .seealso: NEPSetStoppingTest(), NEPStoppingBasic()
791: @*/
792: PetscErrorCode NEPSetStoppingTestFunction(NEP nep,PetscErrorCode (*func)(NEP,PetscInt,PetscInt,PetscInt,PetscInt,NEPConvergedReason*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
793: {
795:   if (nep->stoppingdestroy) (*nep->stoppingdestroy)(nep->stoppingctx);
796:   nep->stoppinguser    = func;
797:   nep->stoppingdestroy = destroy;
798:   nep->stoppingctx     = ctx;
799:   if (func == NEPStoppingBasic) nep->stop = NEP_STOP_BASIC;
800:   else {
801:     nep->stop     = NEP_STOP_USER;
802:     nep->stopping = nep->stoppinguser;
803:   }
804:   return 0;
805: }

807: /*@
808:    NEPSetStoppingTest - Specifies how to decide the termination of the outer
809:    loop of the eigensolver.

811:    Logically Collective on nep

813:    Input Parameters:
814: +  nep  - nonlinear eigensolver context obtained from NEPCreate()
815: -  stop - the type of stopping test

817:    Options Database Keys:
818: +  -nep_stop_basic - Sets the default stopping test
819: -  -nep_stop_user  - Selects the user-defined stopping test

821:    Note:
822:    The parameter 'stop' can have one of these values
823: +     NEP_STOP_BASIC - default stopping test
824: -     NEP_STOP_USER  - function set by NEPSetStoppingTestFunction()

826:    Level: advanced

828: .seealso: NEPGetStoppingTest(), NEPSetStoppingTestFunction(), NEPSetConvergenceTest(), NEPStop
829: @*/
830: PetscErrorCode NEPSetStoppingTest(NEP nep,NEPStop stop)
831: {
834:   switch (stop) {
835:     case NEP_STOP_BASIC: nep->stopping = NEPStoppingBasic; break;
836:     case NEP_STOP_USER:
838:       nep->stopping = nep->stoppinguser;
839:       break;
840:     default:
841:       SETERRQ(PetscObjectComm((PetscObject)nep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'stop' value");
842:   }
843:   nep->stop = stop;
844:   return 0;
845: }

847: /*@
848:    NEPGetStoppingTest - Gets the method used to decide the termination of the outer
849:    loop of the eigensolver.

851:    Not Collective

853:    Input Parameters:
854: .  nep   - nonlinear eigensolver context obtained from NEPCreate()

856:    Output Parameters:
857: .  stop  - the type of stopping test

859:    Level: advanced

861: .seealso: NEPSetStoppingTest(), NEPStop
862: @*/
863: PetscErrorCode NEPGetStoppingTest(NEP nep,NEPStop *stop)
864: {
867:   *stop = nep->stop;
868:   return 0;
869: }

871: /*@
872:    NEPSetTrackAll - Specifies if the solver must compute the residual of all
873:    approximate eigenpairs or not.

875:    Logically Collective on nep

877:    Input Parameters:
878: +  nep      - the eigensolver context
879: -  trackall - whether compute all residuals or not

881:    Notes:
882:    If the user sets trackall=PETSC_TRUE then the solver explicitly computes
883:    the residual for each eigenpair approximation. Computing the residual is
884:    usually an expensive operation and solvers commonly compute the associated
885:    residual to the first unconverged eigenpair.

887:    The option '-nep_monitor_all' automatically activates this option.

889:    Level: developer

891: .seealso: NEPGetTrackAll()
892: @*/
893: PetscErrorCode NEPSetTrackAll(NEP nep,PetscBool trackall)
894: {
897:   nep->trackall = trackall;
898:   return 0;
899: }

901: /*@
902:    NEPGetTrackAll - Returns the flag indicating whether all residual norms must
903:    be computed or not.

905:    Not Collective

907:    Input Parameter:
908: .  nep - the eigensolver context

910:    Output Parameter:
911: .  trackall - the returned flag

913:    Level: developer

915: .seealso: NEPSetTrackAll()
916: @*/
917: PetscErrorCode NEPGetTrackAll(NEP nep,PetscBool *trackall)
918: {
921:   *trackall = nep->trackall;
922:   return 0;
923: }

925: /*@
926:    NEPSetRefine - Specifies the refinement type (and options) to be used
927:    after the solve.

929:    Logically Collective on nep

931:    Input Parameters:
932: +  nep    - the nonlinear eigensolver context
933: .  refine - refinement type
934: .  npart  - number of partitions of the communicator
935: .  tol    - the convergence tolerance
936: .  its    - maximum number of refinement iterations
937: -  scheme - which scheme to be used for solving the involved linear systems

939:    Options Database Keys:
940: +  -nep_refine <type> - refinement type, one of <none,simple,multiple>
941: .  -nep_refine_partitions <n> - the number of partitions
942: .  -nep_refine_tol <tol> - the tolerance
943: .  -nep_refine_its <its> - number of iterations
944: -  -nep_refine_scheme - to set the scheme for the linear solves

946:    Notes:
947:    By default, iterative refinement is disabled, since it may be very
948:    costly. There are two possible refinement strategies, simple and multiple.
949:    The simple approach performs iterative refinement on each of the
950:    converged eigenpairs individually, whereas the multiple strategy works
951:    with the invariant pair as a whole, refining all eigenpairs simultaneously.
952:    The latter may be required for the case of multiple eigenvalues.

954:    In some cases, especially when using direct solvers within the
955:    iterative refinement method, it may be helpful for improved scalability
956:    to split the communicator in several partitions. The npart parameter
957:    indicates how many partitions to use (defaults to 1).

959:    The tol and its parameters specify the stopping criterion. In the simple
960:    method, refinement continues until the residual of each eigenpair is
961:    below the tolerance (tol defaults to the NEP tol, but may be set to a
962:    different value). In contrast, the multiple method simply performs its
963:    refinement iterations (just one by default).

965:    The scheme argument is used to change the way in which linear systems are
966:    solved. Possible choices are explicit, mixed block elimination (MBE),
967:    and Schur complement.

969:    Level: intermediate

971: .seealso: NEPGetRefine()
972: @*/
973: PetscErrorCode NEPSetRefine(NEP nep,NEPRefine refine,PetscInt npart,PetscReal tol,PetscInt its,NEPRefineScheme scheme)
974: {
975:   PetscMPIInt    size;

983:   nep->refine = refine;
984:   if (refine) {  /* process parameters only if not REFINE_NONE */
985:     if (npart!=nep->npart) {
986:       PetscSubcommDestroy(&nep->refinesubc);
987:       KSPDestroy(&nep->refineksp);
988:     }
989:     if (npart == PETSC_DEFAULT || npart == PETSC_DECIDE) {
990:       nep->npart = 1;
991:     } else {
992:       MPI_Comm_size(PetscObjectComm((PetscObject)nep),&size);
994:       nep->npart = npart;
995:     }
996:     if (tol == PETSC_DEFAULT || tol == PETSC_DECIDE) {
997:       nep->rtol = PETSC_DEFAULT;
998:     } else {
1000:       nep->rtol = tol;
1001:     }
1002:     if (its==PETSC_DECIDE || its==PETSC_DEFAULT) {
1003:       nep->rits = PETSC_DEFAULT;
1004:     } else {
1006:       nep->rits = its;
1007:     }
1008:     nep->scheme = scheme;
1009:   }
1010:   nep->state = NEP_STATE_INITIAL;
1011:   return 0;
1012: }

1014: /*@C
1015:    NEPGetRefine - Gets the refinement strategy used by the NEP object, and the
1016:    associated parameters.

1018:    Not Collective

1020:    Input Parameter:
1021: .  nep - the nonlinear eigensolver context

1023:    Output Parameters:
1024: +  refine - refinement type
1025: .  npart  - number of partitions of the communicator
1026: .  tol    - the convergence tolerance
1027: .  its    - maximum number of refinement iterations
1028: -  scheme - the scheme used for solving linear systems

1030:    Level: intermediate

1032:    Note:
1033:    The user can specify NULL for any parameter that is not needed.

1035: .seealso: NEPSetRefine()
1036: @*/
1037: PetscErrorCode NEPGetRefine(NEP nep,NEPRefine *refine,PetscInt *npart,PetscReal *tol,PetscInt *its,NEPRefineScheme *scheme)
1038: {
1040:   if (refine) *refine = nep->refine;
1041:   if (npart)  *npart  = nep->npart;
1042:   if (tol)    *tol    = nep->rtol;
1043:   if (its)    *its    = nep->rits;
1044:   if (scheme) *scheme = nep->scheme;
1045:   return 0;
1046: }

1048: /*@C
1049:    NEPSetOptionsPrefix - Sets the prefix used for searching for all
1050:    NEP options in the database.

1052:    Logically Collective on nep

1054:    Input Parameters:
1055: +  nep - the nonlinear eigensolver context
1056: -  prefix - the prefix string to prepend to all NEP option requests

1058:    Notes:
1059:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1060:    The first character of all runtime options is AUTOMATICALLY the
1061:    hyphen.

1063:    For example, to distinguish between the runtime options for two
1064:    different NEP contexts, one could call
1065: .vb
1066:       NEPSetOptionsPrefix(nep1,"neig1_")
1067:       NEPSetOptionsPrefix(nep2,"neig2_")
1068: .ve

1070:    Level: advanced

1072: .seealso: NEPAppendOptionsPrefix(), NEPGetOptionsPrefix()
1073: @*/
1074: PetscErrorCode NEPSetOptionsPrefix(NEP nep,const char *prefix)
1075: {
1077:   if (!nep->V) NEPGetBV(nep,&nep->V);
1078:   BVSetOptionsPrefix(nep->V,prefix);
1079:   if (!nep->ds) NEPGetDS(nep,&nep->ds);
1080:   DSSetOptionsPrefix(nep->ds,prefix);
1081:   if (!nep->rg) NEPGetRG(nep,&nep->rg);
1082:   RGSetOptionsPrefix(nep->rg,prefix);
1083:   PetscObjectSetOptionsPrefix((PetscObject)nep,prefix);
1084:   return 0;
1085: }

1087: /*@C
1088:    NEPAppendOptionsPrefix - Appends to the prefix used for searching for all
1089:    NEP options in the database.

1091:    Logically Collective on nep

1093:    Input Parameters:
1094: +  nep - the nonlinear eigensolver context
1095: -  prefix - the prefix string to prepend to all NEP option requests

1097:    Notes:
1098:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1099:    The first character of all runtime options is AUTOMATICALLY the hyphen.

1101:    Level: advanced

1103: .seealso: NEPSetOptionsPrefix(), NEPGetOptionsPrefix()
1104: @*/
1105: PetscErrorCode NEPAppendOptionsPrefix(NEP nep,const char *prefix)
1106: {
1108:   if (!nep->V) NEPGetBV(nep,&nep->V);
1109:   BVAppendOptionsPrefix(nep->V,prefix);
1110:   if (!nep->ds) NEPGetDS(nep,&nep->ds);
1111:   DSAppendOptionsPrefix(nep->ds,prefix);
1112:   if (!nep->rg) NEPGetRG(nep,&nep->rg);
1113:   RGAppendOptionsPrefix(nep->rg,prefix);
1114:   PetscObjectAppendOptionsPrefix((PetscObject)nep,prefix);
1115:   return 0;
1116: }

1118: /*@C
1119:    NEPGetOptionsPrefix - Gets the prefix used for searching for all
1120:    NEP options in the database.

1122:    Not Collective

1124:    Input Parameters:
1125: .  nep - the nonlinear eigensolver context

1127:    Output Parameters:
1128: .  prefix - pointer to the prefix string used is returned

1130:    Note:
1131:    On the Fortran side, the user should pass in a string 'prefix' of
1132:    sufficient length to hold the prefix.

1134:    Level: advanced

1136: .seealso: NEPSetOptionsPrefix(), NEPAppendOptionsPrefix()
1137: @*/
1138: PetscErrorCode NEPGetOptionsPrefix(NEP nep,const char *prefix[])
1139: {
1142:   PetscObjectGetOptionsPrefix((PetscObject)nep,prefix);
1143:   return 0;
1144: }