Actual source code: pepopts.c

slepc-3.16.0 2021-09-30
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-2021, 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:    PEP routines related to options that can be set via the command-line
 12:    or procedurally
 13: */

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

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

 22:    Collective on pep

 24:    Input Parameters:
 25: +  pep      - the polynomial 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: PEPMonitorSet(), PEPSetTrackAll()
 34: @*/
 35: PetscErrorCode PEPMonitorSetFromOptions(PEP pep,const char opt[],const char name[],void *ctx,PetscBool trackall)
 36: {
 37:   PetscErrorCode       (*mfunc)(PEP,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;
 46:   PetscErrorCode       ierr;

 49:   PetscOptionsGetViewer(PetscObjectComm((PetscObject)pep),((PetscObject)pep)->options,((PetscObject)pep)->prefix,opt,&viewer,&format,&flg);
 50:   if (!flg) return(0);

 52:   PetscViewerGetType(viewer,&vtype);
 53:   SlepcMonitorMakeKey_Internal(name,vtype,format,key);
 54:   PetscFunctionListFind(PEPMonitorList,key,&mfunc);
 55:   PetscFunctionListFind(PEPMonitorCreateList,key,&cfunc);
 56:   PetscFunctionListFind(PEPMonitorDestroyList,key,&dfunc);
 57:   if (!cfunc) cfunc = PetscViewerAndFormatCreate_Internal;
 58:   if (!dfunc) dfunc = PetscViewerAndFormatDestroy;

 60:   (*cfunc)(viewer,format,ctx,&vf);
 61:   PetscObjectDereference((PetscObject)viewer);
 62:   PEPMonitorSet(pep,mfunc,vf,(PetscErrorCode(*)(void **))dfunc);
 63:   if (trackall) {
 64:     PEPSetTrackAll(pep,PETSC_TRUE);
 65:   }
 66:   return(0);
 67: }

 69: /*@
 70:    PEPSetFromOptions - Sets PEP options from the options database.
 71:    This routine must be called before PEPSetUp() if the user is to be
 72:    allowed to set the solver type.

 74:    Collective on pep

 76:    Input Parameters:
 77: .  pep - the polynomial eigensolver context

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

 82:    Level: beginner
 83: @*/
 84: PetscErrorCode PEPSetFromOptions(PEP pep)
 85: {
 86:   PetscErrorCode  ierr;
 87:   char            type[256];
 88:   PetscBool       set,flg,flg1,flg2,flg3,flg4,flg5;
 89:   PetscReal       r,t,array[2]={0,0};
 90:   PetscScalar     s;
 91:   PetscInt        i,j,k;
 92:   PEPScale        scale;
 93:   PEPRefine       refine;
 94:   PEPRefineScheme scheme;

 98:   PEPRegisterAll();
 99:   PetscObjectOptionsBegin((PetscObject)pep);
100:     PetscOptionsFList("-pep_type","Polynomial eigensolver method","PEPSetType",PEPList,(char*)(((PetscObject)pep)->type_name?((PetscObject)pep)->type_name:PEPTOAR),type,sizeof(type),&flg);
101:     if (flg) {
102:       PEPSetType(pep,type);
103:     } else if (!((PetscObject)pep)->type_name) {
104:       PEPSetType(pep,PEPTOAR);
105:     }

107:     PetscOptionsBoolGroupBegin("-pep_general","General polynomial eigenvalue problem","PEPSetProblemType",&flg);
108:     if (flg) { PEPSetProblemType(pep,PEP_GENERAL); }
109:     PetscOptionsBoolGroup("-pep_hermitian","Hermitian polynomial eigenvalue problem","PEPSetProblemType",&flg);
110:     if (flg) { PEPSetProblemType(pep,PEP_HERMITIAN); }
111:     PetscOptionsBoolGroup("-pep_hyperbolic","Hyperbolic polynomial eigenvalue problem","PEPSetProblemType",&flg);
112:     if (flg) { PEPSetProblemType(pep,PEP_HYPERBOLIC); }
113:     PetscOptionsBoolGroupEnd("-pep_gyroscopic","Gyroscopic polynomial eigenvalue problem","PEPSetProblemType",&flg);
114:     if (flg) { PEPSetProblemType(pep,PEP_GYROSCOPIC); }

116:     scale = pep->scale;
117:     PetscOptionsEnum("-pep_scale","Scaling strategy","PEPSetScale",PEPScaleTypes,(PetscEnum)scale,(PetscEnum*)&scale,&flg1);
118:     r = pep->sfactor;
119:     PetscOptionsReal("-pep_scale_factor","Scale factor","PEPSetScale",pep->sfactor,&r,&flg2);
120:     if (!flg2 && r==1.0) r = PETSC_DEFAULT;
121:     j = pep->sits;
122:     PetscOptionsInt("-pep_scale_its","Number of iterations in diagonal scaling","PEPSetScale",pep->sits,&j,&flg3);
123:     t = pep->slambda;
124:     PetscOptionsReal("-pep_scale_lambda","Estimate of eigenvalue (modulus) for diagonal scaling","PEPSetScale",pep->slambda,&t,&flg4);
125:     if (flg1 || flg2 || flg3 || flg4) { PEPSetScale(pep,scale,r,NULL,NULL,j,t); }

127:     PetscOptionsEnum("-pep_extract","Extraction method","PEPSetExtract",PEPExtractTypes,(PetscEnum)pep->extract,(PetscEnum*)&pep->extract,NULL);

129:     refine = pep->refine;
130:     PetscOptionsEnum("-pep_refine","Iterative refinement method","PEPSetRefine",PEPRefineTypes,(PetscEnum)refine,(PetscEnum*)&refine,&flg1);
131:     i = pep->npart;
132:     PetscOptionsInt("-pep_refine_partitions","Number of partitions of the communicator for iterative refinement","PEPSetRefine",pep->npart,&i,&flg2);
133:     r = pep->rtol;
134:     PetscOptionsReal("-pep_refine_tol","Tolerance for iterative refinement","PEPSetRefine",pep->rtol==PETSC_DEFAULT?SLEPC_DEFAULT_TOL/1000:pep->rtol,&r,&flg3);
135:     j = pep->rits;
136:     PetscOptionsInt("-pep_refine_its","Maximum number of iterations for iterative refinement","PEPSetRefine",pep->rits,&j,&flg4);
137:     scheme = pep->scheme;
138:     PetscOptionsEnum("-pep_refine_scheme","Scheme used for linear systems within iterative refinement","PEPSetRefine",PEPRefineSchemes,(PetscEnum)scheme,(PetscEnum*)&scheme,&flg5);
139:     if (flg1 || flg2 || flg3 || flg4 || flg5) { PEPSetRefine(pep,refine,i,r,j,scheme); }

141:     i = pep->max_it;
142:     PetscOptionsInt("-pep_max_it","Maximum number of iterations","PEPSetTolerances",pep->max_it,&i,&flg1);
143:     r = pep->tol;
144:     PetscOptionsReal("-pep_tol","Tolerance","PEPSetTolerances",SlepcDefaultTol(pep->tol),&r,&flg2);
145:     if (flg1 || flg2) { PEPSetTolerances(pep,r,i); }

147:     PetscOptionsBoolGroupBegin("-pep_conv_rel","Relative error convergence test","PEPSetConvergenceTest",&flg);
148:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_REL); }
149:     PetscOptionsBoolGroup("-pep_conv_norm","Convergence test relative to the matrix norms","PEPSetConvergenceTest",&flg);
150:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_NORM); }
151:     PetscOptionsBoolGroup("-pep_conv_abs","Absolute error convergence test","PEPSetConvergenceTest",&flg);
152:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_ABS); }
153:     PetscOptionsBoolGroupEnd("-pep_conv_user","User-defined convergence test","PEPSetConvergenceTest",&flg);
154:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_USER); }

156:     PetscOptionsBoolGroupBegin("-pep_stop_basic","Stop iteration if all eigenvalues converged or max_it reached","PEPSetStoppingTest",&flg);
157:     if (flg) { PEPSetStoppingTest(pep,PEP_STOP_BASIC); }
158:     PetscOptionsBoolGroupEnd("-pep_stop_user","User-defined stopping test","PEPSetStoppingTest",&flg);
159:     if (flg) { PEPSetStoppingTest(pep,PEP_STOP_USER); }

161:     i = pep->nev;
162:     PetscOptionsInt("-pep_nev","Number of eigenvalues to compute","PEPSetDimensions",pep->nev,&i,&flg1);
163:     j = pep->ncv;
164:     PetscOptionsInt("-pep_ncv","Number of basis vectors","PEPSetDimensions",pep->ncv,&j,&flg2);
165:     k = pep->mpd;
166:     PetscOptionsInt("-pep_mpd","Maximum dimension of projected problem","PEPSetDimensions",pep->mpd,&k,&flg3);
167:     if (flg1 || flg2 || flg3) { PEPSetDimensions(pep,i,j,k); }

169:     PetscOptionsEnum("-pep_basis","Polynomial basis","PEPSetBasis",PEPBasisTypes,(PetscEnum)pep->basis,(PetscEnum*)&pep->basis,NULL);

171:     PetscOptionsBoolGroupBegin("-pep_largest_magnitude","Compute largest eigenvalues in magnitude","PEPSetWhichEigenpairs",&flg);
172:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_LARGEST_MAGNITUDE); }
173:     PetscOptionsBoolGroup("-pep_smallest_magnitude","Compute smallest eigenvalues in magnitude","PEPSetWhichEigenpairs",&flg);
174:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_SMALLEST_MAGNITUDE); }
175:     PetscOptionsBoolGroup("-pep_largest_real","Compute eigenvalues with largest real parts","PEPSetWhichEigenpairs",&flg);
176:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_LARGEST_REAL); }
177:     PetscOptionsBoolGroup("-pep_smallest_real","Compute eigenvalues with smallest real parts","PEPSetWhichEigenpairs",&flg);
178:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_SMALLEST_REAL); }
179:     PetscOptionsBoolGroup("-pep_largest_imaginary","Compute eigenvalues with largest imaginary parts","PEPSetWhichEigenpairs",&flg);
180:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_LARGEST_IMAGINARY); }
181:     PetscOptionsBoolGroup("-pep_smallest_imaginary","Compute eigenvalues with smallest imaginary parts","PEPSetWhichEigenpairs",&flg);
182:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_SMALLEST_IMAGINARY); }
183:     PetscOptionsBoolGroup("-pep_target_magnitude","Compute eigenvalues closest to target","PEPSetWhichEigenpairs",&flg);
184:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_TARGET_MAGNITUDE); }
185:     PetscOptionsBoolGroup("-pep_target_real","Compute eigenvalues with real parts closest to target","PEPSetWhichEigenpairs",&flg);
186:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_TARGET_REAL); }
187:     PetscOptionsBoolGroup("-pep_target_imaginary","Compute eigenvalues with imaginary parts closest to target","PEPSetWhichEigenpairs",&flg);
188:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_TARGET_IMAGINARY); }
189:     PetscOptionsBoolGroupEnd("-pep_all","Compute all eigenvalues in an interval or a region","PEPSetWhichEigenpairs",&flg);
190:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_ALL); }

192:     PetscOptionsScalar("-pep_target","Value of the target","PEPSetTarget",pep->target,&s,&flg);
193:     if (flg) {
194:       if (pep->which!=PEP_TARGET_REAL && pep->which!=PEP_TARGET_IMAGINARY) {
195:         PEPSetWhichEigenpairs(pep,PEP_TARGET_MAGNITUDE);
196:       }
197:       PEPSetTarget(pep,s);
198:     }

200:     k = 2;
201:     PetscOptionsRealArray("-pep_interval","Computational interval (two real values separated with a comma without spaces)","PEPSetInterval",array,&k,&flg);
202:     if (flg) {
203:       if (k<2) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_SIZ,"Must pass two values in -pep_interval (comma-separated without spaces)");
204:       PEPSetWhichEigenpairs(pep,PEP_ALL);
205:       PEPSetInterval(pep,array[0],array[1]);
206:     }

208:     /* -----------------------------------------------------------------------*/
209:     /*
210:       Cancels all monitors hardwired into code before call to PEPSetFromOptions()
211:     */
212:     PetscOptionsBool("-pep_monitor_cancel","Remove any hardwired monitor routines","PEPMonitorCancel",PETSC_FALSE,&flg,&set);
213:     if (set && flg) { PEPMonitorCancel(pep); }
214:     PEPMonitorSetFromOptions(pep,"-pep_monitor","first_approximation",NULL,PETSC_FALSE);
215:     PEPMonitorSetFromOptions(pep,"-pep_monitor_all","all_approximations",NULL,PETSC_TRUE);
216:     PEPMonitorSetFromOptions(pep,"-pep_monitor_conv","convergence_history",NULL,PETSC_FALSE);

218:     /* -----------------------------------------------------------------------*/
219:     PetscOptionsName("-pep_view","Print detailed information on solver used","PEPView",NULL);
220:     PetscOptionsName("-pep_view_vectors","View computed eigenvectors","PEPVectorsView",NULL);
221:     PetscOptionsName("-pep_view_values","View computed eigenvalues","PEPValuesView",NULL);
222:     PetscOptionsName("-pep_converged_reason","Print reason for convergence, and number of iterations","PEPConvergedReasonView",NULL);
223:     PetscOptionsName("-pep_error_absolute","Print absolute errors of each eigenpair","PEPErrorView",NULL);
224:     PetscOptionsName("-pep_error_relative","Print relative errors of each eigenpair","PEPErrorView",NULL);
225:     PetscOptionsName("-pep_error_backward","Print backward errors of each eigenpair","PEPErrorView",NULL);

227:     if (pep->ops->setfromoptions) {
228:       (*pep->ops->setfromoptions)(PetscOptionsObject,pep);
229:     }
230:     PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)pep);
231:   PetscOptionsEnd();

233:   if (!pep->V) { PEPGetBV(pep,&pep->V); }
234:   BVSetFromOptions(pep->V);
235:   if (!pep->rg) { PEPGetRG(pep,&pep->rg); }
236:   RGSetFromOptions(pep->rg);
237:   if (!pep->ds) { PEPGetDS(pep,&pep->ds); }
238:   DSSetFromOptions(pep->ds);
239:   if (!pep->st) { PEPGetST(pep,&pep->st); }
240:   PEPSetDefaultST(pep);
241:   STSetFromOptions(pep->st);
242:   if (!pep->refineksp) { PEPRefineGetKSP(pep,&pep->refineksp); }
243:   KSPSetFromOptions(pep->refineksp);
244:   return(0);
245: }

247: /*@C
248:    PEPGetTolerances - Gets the tolerance and maximum iteration count used
249:    by the PEP convergence tests.

251:    Not Collective

253:    Input Parameter:
254: .  pep - the polynomial eigensolver context

256:    Output Parameters:
257: +  tol - the convergence tolerance
258: -  maxits - maximum number of iterations

260:    Notes:
261:    The user can specify NULL for any parameter that is not needed.

263:    Level: intermediate

265: .seealso: PEPSetTolerances()
266: @*/
267: PetscErrorCode PEPGetTolerances(PEP pep,PetscReal *tol,PetscInt *maxits)
268: {
271:   if (tol)    *tol    = pep->tol;
272:   if (maxits) *maxits = pep->max_it;
273:   return(0);
274: }

276: /*@
277:    PEPSetTolerances - Sets the tolerance and maximum iteration count used
278:    by the PEP convergence tests.

280:    Logically Collective on pep

282:    Input Parameters:
283: +  pep - the polynomial eigensolver context
284: .  tol - the convergence tolerance
285: -  maxits - maximum number of iterations to use

287:    Options Database Keys:
288: +  -pep_tol <tol> - Sets the convergence tolerance
289: -  -pep_max_it <maxits> - Sets the maximum number of iterations allowed

291:    Notes:
292:    Use PETSC_DEFAULT for either argument to assign a reasonably good value.

294:    Level: intermediate

296: .seealso: PEPGetTolerances()
297: @*/
298: PetscErrorCode PEPSetTolerances(PEP pep,PetscReal tol,PetscInt maxits)
299: {
304:   if (tol == PETSC_DEFAULT) {
305:     pep->tol   = PETSC_DEFAULT;
306:     pep->state = PEP_STATE_INITIAL;
307:   } else {
308:     if (tol <= 0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of tol. Must be > 0");
309:     pep->tol = tol;
310:   }
311:   if (maxits == PETSC_DEFAULT || maxits == PETSC_DECIDE) {
312:     pep->max_it = PETSC_DEFAULT;
313:     pep->state  = PEP_STATE_INITIAL;
314:   } else {
315:     if (maxits <= 0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of maxits. Must be > 0");
316:     pep->max_it = maxits;
317:   }
318:   return(0);
319: }

321: /*@C
322:    PEPGetDimensions - Gets the number of eigenvalues to compute
323:    and the dimension of the subspace.

325:    Not Collective

327:    Input Parameter:
328: .  pep - the polynomial eigensolver context

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

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

338:    Level: intermediate

340: .seealso: PEPSetDimensions()
341: @*/
342: PetscErrorCode PEPGetDimensions(PEP pep,PetscInt *nev,PetscInt *ncv,PetscInt *mpd)
343: {
346:   if (nev) *nev = pep->nev;
347:   if (ncv) *ncv = pep->ncv;
348:   if (mpd) *mpd = pep->mpd;
349:   return(0);
350: }

352: /*@
353:    PEPSetDimensions - Sets the number of eigenvalues to compute
354:    and the dimension of the subspace.

356:    Logically Collective on pep

358:    Input Parameters:
359: +  pep - the polynomial eigensolver context
360: .  nev - number of eigenvalues to compute
361: .  ncv - the maximum dimension of the subspace to be used by the solver
362: -  mpd - the maximum dimension allowed for the projected problem

364:    Options Database Keys:
365: +  -pep_nev <nev> - Sets the number of eigenvalues
366: .  -pep_ncv <ncv> - Sets the dimension of the subspace
367: -  -pep_mpd <mpd> - Sets the maximum projected dimension

369:    Notes:
370:    Use PETSC_DEFAULT for ncv and mpd to assign a reasonably good value, which is
371:    dependent on the solution method.

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

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

382:    When computing all eigenvalues in an interval, see PEPSetInterval(), these
383:    parameters lose relevance, and tuning must be done with PEPSTOARSetDimensions().

385:    Level: intermediate

387: .seealso: PEPGetDimensions(), PEPSetInterval(), PEPSTOARSetDimensions()
388: @*/
389: PetscErrorCode PEPSetDimensions(PEP pep,PetscInt nev,PetscInt ncv,PetscInt mpd)
390: {
396:   if (nev<1) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of nev. Must be > 0");
397:   pep->nev = nev;
398:   if (ncv == PETSC_DECIDE || ncv == PETSC_DEFAULT) {
399:     pep->ncv = PETSC_DEFAULT;
400:   } else {
401:     if (ncv<1) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of ncv. Must be > 0");
402:     pep->ncv = ncv;
403:   }
404:   if (mpd == PETSC_DECIDE || mpd == PETSC_DEFAULT) {
405:     pep->mpd = PETSC_DEFAULT;
406:   } else {
407:     if (mpd<1) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of mpd. Must be > 0");
408:     pep->mpd = mpd;
409:   }
410:   pep->state = PEP_STATE_INITIAL;
411:   return(0);
412: }

414: /*@
415:    PEPSetWhichEigenpairs - Specifies which portion of the spectrum is
416:    to be sought.

418:    Logically Collective on pep

420:    Input Parameters:
421: +  pep   - eigensolver context obtained from PEPCreate()
422: -  which - the portion of the spectrum to be sought

424:    Possible values:
425:    The parameter 'which' can have one of these values

427: +     PEP_LARGEST_MAGNITUDE - largest eigenvalues in magnitude (default)
428: .     PEP_SMALLEST_MAGNITUDE - smallest eigenvalues in magnitude
429: .     PEP_LARGEST_REAL - largest real parts
430: .     PEP_SMALLEST_REAL - smallest real parts
431: .     PEP_LARGEST_IMAGINARY - largest imaginary parts
432: .     PEP_SMALLEST_IMAGINARY - smallest imaginary parts
433: .     PEP_TARGET_MAGNITUDE - eigenvalues closest to the target (in magnitude)
434: .     PEP_TARGET_REAL - eigenvalues with real part closest to target
435: .     PEP_TARGET_IMAGINARY - eigenvalues with imaginary part closest to target
436: .     PEP_ALL - all eigenvalues contained in a given interval or region
437: -     PEP_WHICH_USER - user defined ordering set with PEPSetEigenvalueComparison()

439:    Options Database Keys:
440: +   -pep_largest_magnitude - Sets largest eigenvalues in magnitude
441: .   -pep_smallest_magnitude - Sets smallest eigenvalues in magnitude
442: .   -pep_largest_real - Sets largest real parts
443: .   -pep_smallest_real - Sets smallest real parts
444: .   -pep_largest_imaginary - Sets largest imaginary parts
445: .   -pep_smallest_imaginary - Sets smallest imaginary parts
446: .   -pep_target_magnitude - Sets eigenvalues closest to target
447: .   -pep_target_real - Sets real parts closest to target
448: .   -pep_target_imaginary - Sets imaginary parts closest to target
449: -   -pep_all - Sets all eigenvalues in an interval or region

451:    Notes:
452:    Not all eigensolvers implemented in PEP account for all the possible values
453:    stated above. If SLEPc is compiled for real numbers PEP_LARGEST_IMAGINARY
454:    and PEP_SMALLEST_IMAGINARY use the absolute value of the imaginary part
455:    for eigenvalue selection.

457:    The target is a scalar value provided with PEPSetTarget().

459:    The criterion PEP_TARGET_IMAGINARY is available only in case PETSc and
460:    SLEPc have been built with complex scalars.

462:    PEP_ALL is intended for use in combination with an interval (see
463:    PEPSetInterval()), when all eigenvalues within the interval are requested,
464:    and also for computing all eigenvalues in a region with the CISS solver.
465:    In both cases, the number of eigenvalues is unknown, so the nev parameter
466:    has a different sense, see PEPSetDimensions().

468:    Level: intermediate

470: .seealso: PEPGetWhichEigenpairs(), PEPSetTarget(), PEPSetInterval(),
471:           PEPSetDimensions(), PEPSetEigenvalueComparison(), PEPWhich
472: @*/
473: PetscErrorCode PEPSetWhichEigenpairs(PEP pep,PEPWhich which)
474: {
478:   switch (which) {
479:     case PEP_LARGEST_MAGNITUDE:
480:     case PEP_SMALLEST_MAGNITUDE:
481:     case PEP_LARGEST_REAL:
482:     case PEP_SMALLEST_REAL:
483:     case PEP_LARGEST_IMAGINARY:
484:     case PEP_SMALLEST_IMAGINARY:
485:     case PEP_TARGET_MAGNITUDE:
486:     case PEP_TARGET_REAL:
487: #if defined(PETSC_USE_COMPLEX)
488:     case PEP_TARGET_IMAGINARY:
489: #endif
490:     case PEP_ALL:
491:     case PEP_WHICH_USER:
492:       if (pep->which != which) {
493:         pep->state = PEP_STATE_INITIAL;
494:         pep->which = which;
495:       }
496:       break;
497: #if !defined(PETSC_USE_COMPLEX)
498:     case PEP_TARGET_IMAGINARY:
499:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_SUP,"PEP_TARGET_IMAGINARY can be used only with complex scalars");
500: #endif
501:     default:
502:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'which' value");
503:   }
504:   return(0);
505: }

507: /*@
508:     PEPGetWhichEigenpairs - Returns which portion of the spectrum is to be
509:     sought.

511:     Not Collective

513:     Input Parameter:
514: .   pep - eigensolver context obtained from PEPCreate()

516:     Output Parameter:
517: .   which - the portion of the spectrum to be sought

519:     Notes:
520:     See PEPSetWhichEigenpairs() for possible values of 'which'.

522:     Level: intermediate

524: .seealso: PEPSetWhichEigenpairs(), PEPWhich
525: @*/
526: PetscErrorCode PEPGetWhichEigenpairs(PEP pep,PEPWhich *which)
527: {
531:   *which = pep->which;
532:   return(0);
533: }

535: /*@C
536:    PEPSetEigenvalueComparison - Specifies the eigenvalue comparison function
537:    when PEPSetWhichEigenpairs() is set to PEP_WHICH_USER.

539:    Logically Collective on pep

541:    Input Parameters:
542: +  pep  - eigensolver context obtained from PEPCreate()
543: .  func - a pointer to the comparison function
544: -  ctx  - a context pointer (the last parameter to the comparison function)

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

549: +   ar     - real part of the 1st eigenvalue
550: .   ai     - imaginary part of the 1st eigenvalue
551: .   br     - real part of the 2nd eigenvalue
552: .   bi     - imaginary part of the 2nd eigenvalue
553: .   res    - result of comparison
554: -   ctx    - optional context, as set by PEPSetEigenvalueComparison()

556:    Note:
557:    The returning parameter 'res' can be
558: +  negative - if the 1st eigenvalue is preferred to the 2st one
559: .  zero     - if both eigenvalues are equally preferred
560: -  positive - if the 2st eigenvalue is preferred to the 1st one

562:    Level: advanced

564: .seealso: PEPSetWhichEigenpairs(), PEPWhich
565: @*/
566: PetscErrorCode PEPSetEigenvalueComparison(PEP pep,PetscErrorCode (*func)(PetscScalar,PetscScalar,PetscScalar,PetscScalar,PetscInt*,void*),void* ctx)
567: {
570:   pep->sc->comparison    = func;
571:   pep->sc->comparisonctx = ctx;
572:   pep->which             = PEP_WHICH_USER;
573:   return(0);
574: }

576: /*@
577:    PEPSetProblemType - Specifies the type of the polynomial eigenvalue problem.

579:    Logically Collective on pep

581:    Input Parameters:
582: +  pep  - the polynomial eigensolver context
583: -  type - a known type of polynomial eigenvalue problem

585:    Options Database Keys:
586: +  -pep_general - general problem with no particular structure
587: .  -pep_hermitian - problem whose coefficient matrices are Hermitian
588: .  -pep_hyperbolic - Hermitian problem that satisfies the definition of hyperbolic
589: -  -pep_gyroscopic - problem with Hamiltonian structure

591:    Notes:
592:    Allowed values for the problem type are: general (PEP_GENERAL), Hermitian
593:    (PEP_HERMITIAN), hyperbolic (PEP_HYPERBOLIC), and gyroscopic (PEP_GYROSCOPIC).

595:    This function is used to instruct SLEPc to exploit certain structure in
596:    the polynomial eigenproblem. By default, no particular structure is assumed.

598:    If the problem matrices are Hermitian (symmetric in the real case) or
599:    Hermitian/skew-Hermitian then the solver can exploit this fact to perform
600:    less operations or provide better stability. Hyperbolic problems are a
601:    particular case of Hermitian problems, some solvers may treat them simply as
602:    Hermitian.

604:    Level: intermediate

606: .seealso: PEPSetOperators(), PEPSetType(), PEPGetProblemType(), PEPProblemType
607: @*/
608: PetscErrorCode PEPSetProblemType(PEP pep,PEPProblemType type)
609: {
613:   if (type!=PEP_GENERAL && type!=PEP_HERMITIAN && type!=PEP_HYPERBOLIC && type!=PEP_GYROSCOPIC) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_WRONG,"Unknown eigenvalue problem type");
614:   if (type != pep->problem_type) {
615:     pep->problem_type = type;
616:     pep->state = PEP_STATE_INITIAL;
617:   }
618:   return(0);
619: }

621: /*@
622:    PEPGetProblemType - Gets the problem type from the PEP object.

624:    Not Collective

626:    Input Parameter:
627: .  pep - the polynomial eigensolver context

629:    Output Parameter:
630: .  type - the problem type

632:    Level: intermediate

634: .seealso: PEPSetProblemType(), PEPProblemType
635: @*/
636: PetscErrorCode PEPGetProblemType(PEP pep,PEPProblemType *type)
637: {
641:   *type = pep->problem_type;
642:   return(0);
643: }

645: /*@
646:    PEPSetBasis - Specifies the type of polynomial basis used to describe the
647:    polynomial eigenvalue problem.

649:    Logically Collective on pep

651:    Input Parameters:
652: +  pep   - the polynomial eigensolver context
653: -  basis - the type of polynomial basis

655:    Options Database Key:
656: .  -pep_basis <basis> - Select the basis type

658:    Notes:
659:    By default, the coefficient matrices passed via PEPSetOperators() are
660:    expressed in the monomial basis, i.e.
661:    P(lambda) = A_0 + lambda*A_1 + lambda^2*A_2 + ... + lambda^d*A_d.
662:    Other polynomial bases may have better numerical behaviour, but the user
663:    must then pass the coefficient matrices accordingly.

665:    Level: intermediate

667: .seealso: PEPSetOperators(), PEPGetBasis(), PEPBasis
668: @*/
669: PetscErrorCode PEPSetBasis(PEP pep,PEPBasis basis)
670: {
674:   pep->basis = basis;
675:   return(0);
676: }

678: /*@
679:    PEPGetBasis - Gets the type of polynomial basis from the PEP object.

681:    Not Collective

683:    Input Parameter:
684: .  pep - the polynomial eigensolver context

686:    Output Parameter:
687: .  basis - the polynomial basis

689:    Level: intermediate

691: .seealso: PEPSetBasis(), PEPBasis
692: @*/
693: PetscErrorCode PEPGetBasis(PEP pep,PEPBasis *basis)
694: {
698:   *basis = pep->basis;
699:   return(0);
700: }

702: /*@
703:    PEPSetTrackAll - Specifies if the solver must compute the residual of all
704:    approximate eigenpairs or not.

706:    Logically Collective on pep

708:    Input Parameters:
709: +  pep      - the eigensolver context
710: -  trackall - whether compute all residuals or not

712:    Notes:
713:    If the user sets trackall=PETSC_TRUE then the solver explicitly computes
714:    the residual for each eigenpair approximation. Computing the residual is
715:    usually an expensive operation and solvers commonly compute the associated
716:    residual to the first unconverged eigenpair.

718:    The option '-pep_monitor_all' automatically activates this option.

720:    Level: developer

722: .seealso: PEPGetTrackAll()
723: @*/
724: PetscErrorCode PEPSetTrackAll(PEP pep,PetscBool trackall)
725: {
729:   pep->trackall = trackall;
730:   return(0);
731: }

733: /*@
734:    PEPGetTrackAll - Returns the flag indicating whether all residual norms must
735:    be computed or not.

737:    Not Collective

739:    Input Parameter:
740: .  pep - the eigensolver context

742:    Output Parameter:
743: .  trackall - the returned flag

745:    Level: developer

747: .seealso: PEPSetTrackAll()
748: @*/
749: PetscErrorCode PEPGetTrackAll(PEP pep,PetscBool *trackall)
750: {
754:   *trackall = pep->trackall;
755:   return(0);
756: }

758: /*@C
759:    PEPSetConvergenceTestFunction - Sets a function to compute the error estimate
760:    used in the convergence test.

762:    Logically Collective on pep

764:    Input Parameters:
765: +  pep     - eigensolver context obtained from PEPCreate()
766: .  func    - a pointer to the convergence test function
767: .  ctx     - context for private data for the convergence routine (may be null)
768: -  destroy - a routine for destroying the context (may be null)

770:    Calling Sequence of func:
771: $   func(PEP pep,PetscScalar eigr,PetscScalar eigi,PetscReal res,PetscReal *errest,void *ctx)

773: +   pep    - eigensolver context obtained from PEPCreate()
774: .   eigr   - real part of the eigenvalue
775: .   eigi   - imaginary part of the eigenvalue
776: .   res    - residual norm associated to the eigenpair
777: .   errest - (output) computed error estimate
778: -   ctx    - optional context, as set by PEPSetConvergenceTestFunction()

780:    Note:
781:    If the error estimate returned by the convergence test function is less than
782:    the tolerance, then the eigenvalue is accepted as converged.

784:    Level: advanced

786: .seealso: PEPSetConvergenceTest(), PEPSetTolerances()
787: @*/
788: PetscErrorCode PEPSetConvergenceTestFunction(PEP pep,PetscErrorCode (*func)(PEP,PetscScalar,PetscScalar,PetscReal,PetscReal*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
789: {

794:   if (pep->convergeddestroy) {
795:     (*pep->convergeddestroy)(pep->convergedctx);
796:   }
797:   pep->convergeduser    = func;
798:   pep->convergeddestroy = destroy;
799:   pep->convergedctx     = ctx;
800:   if (func == PEPConvergedRelative) pep->conv = PEP_CONV_REL;
801:   else if (func == PEPConvergedNorm) pep->conv = PEP_CONV_NORM;
802:   else if (func == PEPConvergedAbsolute) pep->conv = PEP_CONV_ABS;
803:   else {
804:     pep->conv      = PEP_CONV_USER;
805:     pep->converged = pep->convergeduser;
806:   }
807:   return(0);
808: }

810: /*@
811:    PEPSetConvergenceTest - Specifies how to compute the error estimate
812:    used in the convergence test.

814:    Logically Collective on pep

816:    Input Parameters:
817: +  pep  - eigensolver context obtained from PEPCreate()
818: -  conv - the type of convergence test

820:    Options Database Keys:
821: +  -pep_conv_abs    - Sets the absolute convergence test
822: .  -pep_conv_rel    - Sets the convergence test relative to the eigenvalue
823: .  -pep_conv_norm   - Sets the convergence test relative to the matrix norms
824: -  -pep_conv_user   - Selects the user-defined convergence test

826:    Note:
827:    The parameter 'conv' can have one of these values
828: +     PEP_CONV_ABS    - absolute error ||r||
829: .     PEP_CONV_REL    - error relative to the eigenvalue l, ||r||/|l|
830: .     PEP_CONV_NORM   - error relative matrix norms, ||r||/sum_i(l^i*||A_i||)
831: -     PEP_CONV_USER   - function set by PEPSetConvergenceTestFunction()

833:    Level: intermediate

835: .seealso: PEPGetConvergenceTest(), PEPSetConvergenceTestFunction(), PEPSetStoppingTest(), PEPConv
836: @*/
837: PetscErrorCode PEPSetConvergenceTest(PEP pep,PEPConv conv)
838: {
842:   switch (conv) {
843:     case PEP_CONV_ABS:  pep->converged = PEPConvergedAbsolute; break;
844:     case PEP_CONV_REL:  pep->converged = PEPConvergedRelative; break;
845:     case PEP_CONV_NORM: pep->converged = PEPConvergedNorm; break;
846:     case PEP_CONV_USER:
847:       if (!pep->convergeduser) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ORDER,"Must call PEPSetConvergenceTestFunction() first");
848:       pep->converged = pep->convergeduser;
849:       break;
850:     default:
851:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'conv' value");
852:   }
853:   pep->conv = conv;
854:   return(0);
855: }

857: /*@
858:    PEPGetConvergenceTest - Gets the method used to compute the error estimate
859:    used in the convergence test.

861:    Not Collective

863:    Input Parameters:
864: .  pep   - eigensolver context obtained from PEPCreate()

866:    Output Parameters:
867: .  conv  - the type of convergence test

869:    Level: intermediate

871: .seealso: PEPSetConvergenceTest(), PEPConv
872: @*/
873: PetscErrorCode PEPGetConvergenceTest(PEP pep,PEPConv *conv)
874: {
878:   *conv = pep->conv;
879:   return(0);
880: }

882: /*@C
883:    PEPSetStoppingTestFunction - Sets a function to decide when to stop the outer
884:    iteration of the eigensolver.

886:    Logically Collective on pep

888:    Input Parameters:
889: +  pep     - eigensolver context obtained from PEPCreate()
890: .  func    - pointer to the stopping test function
891: .  ctx     - context for private data for the stopping routine (may be null)
892: -  destroy - a routine for destroying the context (may be null)

894:    Calling Sequence of func:
895: $   func(PEP pep,PetscInt its,PetscInt max_it,PetscInt nconv,PetscInt nev,PEPConvergedReason *reason,void *ctx)

897: +   pep    - eigensolver context obtained from PEPCreate()
898: .   its    - current number of iterations
899: .   max_it - maximum number of iterations
900: .   nconv  - number of currently converged eigenpairs
901: .   nev    - number of requested eigenpairs
902: .   reason - (output) result of the stopping test
903: -   ctx    - optional context, as set by PEPSetStoppingTestFunction()

905:    Note:
906:    Normal usage is to first call the default routine PEPStoppingBasic() and then
907:    set reason to PEP_CONVERGED_USER if some user-defined conditions have been
908:    met. To let the eigensolver continue iterating, the result must be left as
909:    PEP_CONVERGED_ITERATING.

911:    Level: advanced

913: .seealso: PEPSetStoppingTest(), PEPStoppingBasic()
914: @*/
915: PetscErrorCode PEPSetStoppingTestFunction(PEP pep,PetscErrorCode (*func)(PEP,PetscInt,PetscInt,PetscInt,PetscInt,PEPConvergedReason*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
916: {

921:   if (pep->stoppingdestroy) {
922:     (*pep->stoppingdestroy)(pep->stoppingctx);
923:   }
924:   pep->stoppinguser    = func;
925:   pep->stoppingdestroy = destroy;
926:   pep->stoppingctx     = ctx;
927:   if (func == PEPStoppingBasic) pep->stop = PEP_STOP_BASIC;
928:   else {
929:     pep->stop     = PEP_STOP_USER;
930:     pep->stopping = pep->stoppinguser;
931:   }
932:   return(0);
933: }

935: /*@
936:    PEPSetStoppingTest - Specifies how to decide the termination of the outer
937:    loop of the eigensolver.

939:    Logically Collective on pep

941:    Input Parameters:
942: +  pep  - eigensolver context obtained from PEPCreate()
943: -  stop - the type of stopping test

945:    Options Database Keys:
946: +  -pep_stop_basic - Sets the default stopping test
947: -  -pep_stop_user  - Selects the user-defined stopping test

949:    Note:
950:    The parameter 'stop' can have one of these values
951: +     PEP_STOP_BASIC - default stopping test
952: -     PEP_STOP_USER  - function set by PEPSetStoppingTestFunction()

954:    Level: advanced

956: .seealso: PEPGetStoppingTest(), PEPSetStoppingTestFunction(), PEPSetConvergenceTest(), PEPStop
957: @*/
958: PetscErrorCode PEPSetStoppingTest(PEP pep,PEPStop stop)
959: {
963:   switch (stop) {
964:     case PEP_STOP_BASIC: pep->stopping = PEPStoppingBasic; break;
965:     case PEP_STOP_USER:
966:       if (!pep->stoppinguser) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ORDER,"Must call PEPSetStoppingTestFunction() first");
967:       pep->stopping = pep->stoppinguser;
968:       break;
969:     default:
970:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'stop' value");
971:   }
972:   pep->stop = stop;
973:   return(0);
974: }

976: /*@
977:    PEPGetStoppingTest - Gets the method used to decide the termination of the outer
978:    loop of the eigensolver.

980:    Not Collective

982:    Input Parameters:
983: .  pep   - eigensolver context obtained from PEPCreate()

985:    Output Parameters:
986: .  stop  - the type of stopping test

988:    Level: advanced

990: .seealso: PEPSetStoppingTest(), PEPStop
991: @*/
992: PetscErrorCode PEPGetStoppingTest(PEP pep,PEPStop *stop)
993: {
997:   *stop = pep->stop;
998:   return(0);
999: }

1001: /*@
1002:    PEPSetScale - Specifies the scaling strategy to be used.

1004:    Logically Collective on pep

1006:    Input Parameters:
1007: +  pep    - the eigensolver context
1008: .  scale  - scaling strategy
1009: .  alpha  - the scaling factor used in the scalar strategy
1010: .  Dl     - the left diagonal matrix of the diagonal scaling algorithm
1011: .  Dr     - the right diagonal matrix of the diagonal scaling algorithm
1012: .  its    - number of iterations of the diagonal scaling algorithm
1013: -  lambda - approximation to wanted eigenvalues (modulus)

1015:    Options Database Keys:
1016: +  -pep_scale <type> - scaling type, one of <none,scalar,diagonal,both>
1017: .  -pep_scale_factor <alpha> - the scaling factor
1018: .  -pep_scale_its <its> - number of iterations
1019: -  -pep_scale_lambda <lambda> - approximation to eigenvalues

1021:    Notes:
1022:    There are two non-exclusive scaling strategies: scalar and diagonal.

1024:    In the scalar strategy, scaling is applied to the eigenvalue, that is,
1025:    mu = lambda/alpha is the new eigenvalue and all matrices are scaled
1026:    accordingly. After solving the scaled problem, the original lambda is
1027:    recovered. Parameter 'alpha' must be positive. Use PETSC_DEFAULT to let
1028:    the solver compute a reasonable scaling factor.

1030:    In the diagonal strategy, the solver works implicitly with matrix Dl*A*Dr,
1031:    where Dl and Dr are appropriate diagonal matrices. This improves the accuracy
1032:    of the computed results in some cases. The user may provide the Dr and Dl
1033:    matrices represented as Vec objects storing diagonal elements. If not
1034:    provided, these matrices are computed internally. This option requires
1035:    that the polynomial coefficient matrices are of MATAIJ type.
1036:    The parameter 'its' is the number of iterations performed by the method.
1037:    Parameter 'lambda' must be positive. Use PETSC_DEFAULT or set lambda = 1.0 if
1038:    no information about eigenvalues is available.

1040:    Level: intermediate

1042: .seealso: PEPGetScale()
1043: @*/
1044: PetscErrorCode PEPSetScale(PEP pep,PEPScale scale,PetscReal alpha,Vec Dl,Vec Dr,PetscInt its,PetscReal lambda)
1045: {

1051:   pep->scale = scale;
1052:   if (scale==PEP_SCALE_SCALAR || scale==PEP_SCALE_BOTH) {
1054:     if (alpha == PETSC_DEFAULT || alpha == PETSC_DECIDE) {
1055:       pep->sfactor = 0.0;
1056:       pep->sfactor_set = PETSC_FALSE;
1057:     } else {
1058:       if (alpha<=0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of alpha. Must be > 0");
1059:       pep->sfactor = alpha;
1060:       pep->sfactor_set = PETSC_TRUE;
1061:     }
1062:   }
1063:   if (scale==PEP_SCALE_DIAGONAL || scale==PEP_SCALE_BOTH) {
1064:     if (Dl) {
1067:       PetscObjectReference((PetscObject)Dl);
1068:       VecDestroy(&pep->Dl);
1069:       pep->Dl = Dl;
1070:     }
1071:     if (Dr) {
1074:       PetscObjectReference((PetscObject)Dr);
1075:       VecDestroy(&pep->Dr);
1076:       pep->Dr = Dr;
1077:     }
1080:     if (its==PETSC_DECIDE || its==PETSC_DEFAULT) pep->sits = 5;
1081:     else pep->sits = its;
1082:     if (lambda==PETSC_DECIDE || lambda==PETSC_DEFAULT) pep->slambda = 1.0;
1083:     else if (lambda<=0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of lambda. Must be > 0");
1084:     else pep->slambda = lambda;
1085:   }
1086:   pep->state = PEP_STATE_INITIAL;
1087:   return(0);
1088: }

1090: /*@C
1091:    PEPGetScale - Gets the scaling strategy used by the PEP object, and the
1092:    associated parameters.

1094:    Not Collectiv, but vectors are shared by all processors that share the PEP

1096:    Input Parameter:
1097: .  pep - the eigensolver context

1099:    Output Parameters:
1100: +  scale  - scaling strategy
1101: .  alpha  - the scaling factor used in the scalar strategy
1102: .  Dl     - the left diagonal matrix of the diagonal scaling algorithm
1103: .  Dr     - the right diagonal matrix of the diagonal scaling algorithm
1104: .  its    - number of iterations of the diagonal scaling algorithm
1105: -  lambda - approximation to wanted eigenvalues (modulus)

1107:    Level: intermediate

1109:    Note:
1110:    The user can specify NULL for any parameter that is not needed.

1112:    If Dl or Dr were not set by the user, then the ones computed internally are
1113:    returned (or a null pointer if called before PEPSetUp).

1115: .seealso: PEPSetScale(), PEPSetUp()
1116: @*/
1117: PetscErrorCode PEPGetScale(PEP pep,PEPScale *scale,PetscReal *alpha,Vec *Dl,Vec *Dr,PetscInt *its,PetscReal *lambda)
1118: {
1121:   if (scale)  *scale  = pep->scale;
1122:   if (alpha)  *alpha  = pep->sfactor;
1123:   if (Dl)     *Dl     = pep->Dl;
1124:   if (Dr)     *Dr     = pep->Dr;
1125:   if (its)    *its    = pep->sits;
1126:   if (lambda) *lambda = pep->slambda;
1127:   return(0);
1128: }

1130: /*@
1131:    PEPSetExtract - Specifies the extraction strategy to be used.

1133:    Logically Collective on pep

1135:    Input Parameters:
1136: +  pep     - the eigensolver context
1137: -  extract - extraction strategy

1139:    Options Database Keys:
1140: .  -pep_extract <type> - extraction type, one of <none,norm,residual,structured>

1142:    Level: intermediate

1144: .seealso: PEPGetExtract()
1145: @*/
1146: PetscErrorCode PEPSetExtract(PEP pep,PEPExtract extract)
1147: {
1151:   pep->extract = extract;
1152:   return(0);
1153: }

1155: /*@
1156:    PEPGetExtract - Gets the extraction strategy used by the PEP object.

1158:    Not Collective

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

1163:    Output Parameter:
1164: .  extract - extraction strategy

1166:    Level: intermediate

1168: .seealso: PEPSetExtract(), PEPExtract
1169: @*/
1170: PetscErrorCode PEPGetExtract(PEP pep,PEPExtract *extract)
1171: {
1175:   *extract = pep->extract;
1176:   return(0);
1177: }

1179: /*@
1180:    PEPSetRefine - Specifies the refinement type (and options) to be used
1181:    after the solve.

1183:    Logically Collective on pep

1185:    Input Parameters:
1186: +  pep    - the polynomial eigensolver context
1187: .  refine - refinement type
1188: .  npart  - number of partitions of the communicator
1189: .  tol    - the convergence tolerance
1190: .  its    - maximum number of refinement iterations
1191: -  scheme - which scheme to be used for solving the involved linear systems

1193:    Options Database Keys:
1194: +  -pep_refine <type> - refinement type, one of <none,simple,multiple>
1195: .  -pep_refine_partitions <n> - the number of partitions
1196: .  -pep_refine_tol <tol> - the tolerance
1197: .  -pep_refine_its <its> - number of iterations
1198: -  -pep_refine_scheme - to set the scheme for the linear solves

1200:    Notes:
1201:    By default, iterative refinement is disabled, since it may be very
1202:    costly. There are two possible refinement strategies: simple and multiple.
1203:    The simple approach performs iterative refinement on each of the
1204:    converged eigenpairs individually, whereas the multiple strategy works
1205:    with the invariant pair as a whole, refining all eigenpairs simultaneously.
1206:    The latter may be required for the case of multiple eigenvalues.

1208:    In some cases, especially when using direct solvers within the
1209:    iterative refinement method, it may be helpful for improved scalability
1210:    to split the communicator in several partitions. The npart parameter
1211:    indicates how many partitions to use (defaults to 1).

1213:    The tol and its parameters specify the stopping criterion. In the simple
1214:    method, refinement continues until the residual of each eigenpair is
1215:    below the tolerance (tol defaults to the PEP tol, but may be set to a
1216:    different value). In contrast, the multiple method simply performs its
1217:    refinement iterations (just one by default).

1219:    The scheme argument is used to change the way in which linear systems are
1220:    solved. Possible choices are: explicit, mixed block elimination (MBE),
1221:    and Schur complement.

1223:    Level: intermediate

1225: .seealso: PEPGetRefine()
1226: @*/
1227: PetscErrorCode PEPSetRefine(PEP pep,PEPRefine refine,PetscInt npart,PetscReal tol,PetscInt its,PEPRefineScheme scheme)
1228: {
1230:   PetscMPIInt    size;

1239:   pep->refine = refine;
1240:   if (refine) {  /* process parameters only if not REFINE_NONE */
1241:     if (npart!=pep->npart) {
1242:       PetscSubcommDestroy(&pep->refinesubc);
1243:       KSPDestroy(&pep->refineksp);
1244:     }
1245:     if (npart == PETSC_DEFAULT || npart == PETSC_DECIDE) {
1246:       pep->npart = 1;
1247:     } else {
1248:       MPI_Comm_size(PetscObjectComm((PetscObject)pep),&size);
1249:       if (npart<1 || npart>size) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of npart");
1250:       pep->npart = npart;
1251:     }
1252:     if (tol == PETSC_DEFAULT || tol == PETSC_DECIDE) {
1253:       pep->rtol = PETSC_DEFAULT;
1254:     } else {
1255:       if (tol<=0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of tol. Must be > 0");
1256:       pep->rtol = tol;
1257:     }
1258:     if (its==PETSC_DECIDE || its==PETSC_DEFAULT) {
1259:       pep->rits = PETSC_DEFAULT;
1260:     } else {
1261:       if (its<0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of its. Must be >= 0");
1262:       pep->rits = its;
1263:     }
1264:     pep->scheme = scheme;
1265:   }
1266:   pep->state = PEP_STATE_INITIAL;
1267:   return(0);
1268: }

1270: /*@C
1271:    PEPGetRefine - Gets the refinement strategy used by the PEP object, and the
1272:    associated parameters.

1274:    Not Collective

1276:    Input Parameter:
1277: .  pep - the polynomial eigensolver context

1279:    Output Parameters:
1280: +  refine - refinement type
1281: .  npart  - number of partitions of the communicator
1282: .  tol    - the convergence tolerance
1283: .  its    - maximum number of refinement iterations
1284: -  scheme - the scheme used for solving linear systems

1286:    Level: intermediate

1288:    Note:
1289:    The user can specify NULL for any parameter that is not needed.

1291: .seealso: PEPSetRefine()
1292: @*/
1293: PetscErrorCode PEPGetRefine(PEP pep,PEPRefine *refine,PetscInt *npart,PetscReal *tol,PetscInt *its,PEPRefineScheme *scheme)
1294: {
1297:   if (refine) *refine = pep->refine;
1298:   if (npart)  *npart  = pep->npart;
1299:   if (tol)    *tol    = pep->rtol;
1300:   if (its)    *its    = pep->rits;
1301:   if (scheme) *scheme = pep->scheme;
1302:   return(0);
1303: }

1305: /*@C
1306:    PEPSetOptionsPrefix - Sets the prefix used for searching for all
1307:    PEP options in the database.

1309:    Logically Collective on pep

1311:    Input Parameters:
1312: +  pep - the polynomial eigensolver context
1313: -  prefix - the prefix string to prepend to all PEP option requests

1315:    Notes:
1316:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1317:    The first character of all runtime options is AUTOMATICALLY the
1318:    hyphen.

1320:    For example, to distinguish between the runtime options for two
1321:    different PEP contexts, one could call
1322: .vb
1323:       PEPSetOptionsPrefix(pep1,"qeig1_")
1324:       PEPSetOptionsPrefix(pep2,"qeig2_")
1325: .ve

1327:    Level: advanced

1329: .seealso: PEPAppendOptionsPrefix(), PEPGetOptionsPrefix()
1330: @*/
1331: PetscErrorCode PEPSetOptionsPrefix(PEP pep,const char *prefix)
1332: {

1337:   if (!pep->st) { PEPGetST(pep,&pep->st); }
1338:   STSetOptionsPrefix(pep->st,prefix);
1339:   if (!pep->V) { PEPGetBV(pep,&pep->V); }
1340:   BVSetOptionsPrefix(pep->V,prefix);
1341:   if (!pep->ds) { PEPGetDS(pep,&pep->ds); }
1342:   DSSetOptionsPrefix(pep->ds,prefix);
1343:   if (!pep->rg) { PEPGetRG(pep,&pep->rg); }
1344:   RGSetOptionsPrefix(pep->rg,prefix);
1345:   PetscObjectSetOptionsPrefix((PetscObject)pep,prefix);
1346:   return(0);
1347: }

1349: /*@C
1350:    PEPAppendOptionsPrefix - Appends to the prefix used for searching for all
1351:    PEP options in the database.

1353:    Logically Collective on pep

1355:    Input Parameters:
1356: +  pep - the polynomial eigensolver context
1357: -  prefix - the prefix string to prepend to all PEP option requests

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

1363:    Level: advanced

1365: .seealso: PEPSetOptionsPrefix(), PEPGetOptionsPrefix()
1366: @*/
1367: PetscErrorCode PEPAppendOptionsPrefix(PEP pep,const char *prefix)
1368: {

1373:   if (!pep->st) { PEPGetST(pep,&pep->st); }
1374:   STAppendOptionsPrefix(pep->st,prefix);
1375:   if (!pep->V) { PEPGetBV(pep,&pep->V); }
1376:   BVAppendOptionsPrefix(pep->V,prefix);
1377:   if (!pep->ds) { PEPGetDS(pep,&pep->ds); }
1378:   DSAppendOptionsPrefix(pep->ds,prefix);
1379:   if (!pep->rg) { PEPGetRG(pep,&pep->rg); }
1380:   RGAppendOptionsPrefix(pep->rg,prefix);
1381:   PetscObjectAppendOptionsPrefix((PetscObject)pep,prefix);
1382:   return(0);
1383: }

1385: /*@C
1386:    PEPGetOptionsPrefix - Gets the prefix used for searching for all
1387:    PEP options in the database.

1389:    Not Collective

1391:    Input Parameters:
1392: .  pep - the polynomial eigensolver context

1394:    Output Parameters:
1395: .  prefix - pointer to the prefix string used is returned

1397:    Note:
1398:    On the Fortran side, the user should pass in a string 'prefix' of
1399:    sufficient length to hold the prefix.

1401:    Level: advanced

1403: .seealso: PEPSetOptionsPrefix(), PEPAppendOptionsPrefix()
1404: @*/
1405: PetscErrorCode PEPGetOptionsPrefix(PEP pep,const char *prefix[])
1406: {

1412:   PetscObjectGetOptionsPrefix((PetscObject)pep,prefix);
1413:   return(0);
1414: }