Actual source code: pepopts.c

slepc-3.9.0 2018-04-12
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-2018, 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>       /*I "slepcpep.h" I*/
 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: .  name     - the monitor option name
 27: .  help     - message indicating what monitoring is done
 28: .  manual   - manual page for the monitor
 29: .  monitor  - the monitor function, whose context is a PetscViewerAndFormat
 30: -  trackall - whether this monitor tracks all eigenvalues or not

 32:    Level: developer

 34: .seealso: PEPMonitorSet(), PEPSetTrackAll(), PEPConvMonitorSetFromOptions()
 35: @*/
 36: PetscErrorCode PEPMonitorSetFromOptions(PEP pep,const char name[],const char help[],const char manual[],PetscErrorCode (*monitor)(PEP,PetscInt,PetscInt,PetscScalar*,PetscScalar*,PetscReal*,PetscInt,PetscViewerAndFormat*),PetscBool trackall)
 37: {
 38:   PetscErrorCode       ierr;
 39:   PetscBool            flg;
 40:   PetscViewer          viewer;
 41:   PetscViewerFormat    format;
 42:   PetscViewerAndFormat *vf;

 45:   PetscOptionsGetViewer(PetscObjectComm((PetscObject)pep),((PetscObject)pep)->prefix,name,&viewer,&format,&flg);
 46:   if (flg) {
 47:     PetscViewerAndFormatCreate(viewer,format,&vf);
 48:     PetscObjectDereference((PetscObject)viewer);
 49:     PEPMonitorSet(pep,(PetscErrorCode (*)(PEP,PetscInt,PetscInt,PetscScalar*,PetscScalar*,PetscReal*,PetscInt,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);
 50:     if (trackall) {
 51:       PEPSetTrackAll(pep,PETSC_TRUE);
 52:     }
 53:   }
 54:   return(0);
 55: }

 57: /*@C
 58:    PEPConvMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type
 59:    indicated by the user (for monitors that only show iteration numbers of convergence).

 61:    Collective on PEP

 63:    Input Parameters:
 64: +  pep      - the polynomial eigensolver context
 65: .  name     - the monitor option name
 66: .  help     - message indicating what monitoring is done
 67: .  manual   - manual page for the monitor
 68: -  monitor  - the monitor function, whose context is a SlepcConvMonitor

 70:    Level: developer

 72: .seealso: PEPMonitorSet(), PEPMonitorSetFromOptions()
 73: @*/
 74: PetscErrorCode PEPConvMonitorSetFromOptions(PEP pep,const char name[],const char help[],const char manual[],PetscErrorCode (*monitor)(PEP,PetscInt,PetscInt,PetscScalar*,PetscScalar*,PetscReal*,PetscInt,SlepcConvMonitor))
 75: {
 76:   PetscErrorCode    ierr;
 77:   PetscBool         flg;
 78:   PetscViewer       viewer;
 79:   PetscViewerFormat format;
 80:   SlepcConvMonitor  ctx;

 83:   PetscOptionsGetViewer(PetscObjectComm((PetscObject)pep),((PetscObject)pep)->prefix,name,&viewer,&format,&flg);
 84:   if (flg) {
 85:     SlepcConvMonitorCreate(viewer,format,&ctx);
 86:     PetscObjectDereference((PetscObject)viewer);
 87:     PEPMonitorSet(pep,(PetscErrorCode (*)(PEP,PetscInt,PetscInt,PetscScalar*,PetscScalar*,PetscReal*,PetscInt,void*))monitor,ctx,(PetscErrorCode (*)(void**))SlepcConvMonitorDestroy);
 88:   }
 89:   return(0);
 90: }

 92: /*@
 93:    PEPSetFromOptions - Sets PEP options from the options database.
 94:    This routine must be called before PEPSetUp() if the user is to be
 95:    allowed to set the solver type.

 97:    Collective on PEP

 99:    Input Parameters:
100: .  pep - the polynomial eigensolver context

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

105:    Level: beginner
106: @*/
107: PetscErrorCode PEPSetFromOptions(PEP pep)
108: {
109:   PetscErrorCode  ierr;
110:   char            type[256];
111:   PetscBool       set,flg,flg1,flg2,flg3,flg4,flg5;
112:   PetscReal       r,t,array[2]={0,0};
113:   PetscScalar     s;
114:   PetscInt        i,j,k;
115:   PetscDrawLG     lg;
116:   PEPScale        scale;
117:   PEPRefine       refine;
118:   PEPRefineScheme scheme;

122:   PEPRegisterAll();
123:   PetscObjectOptionsBegin((PetscObject)pep);
124:     PetscOptionsFList("-pep_type","Polynomial eigensolver method","PEPSetType",PEPList,(char*)(((PetscObject)pep)->type_name?((PetscObject)pep)->type_name:PEPTOAR),type,256,&flg);
125:     if (flg) {
126:       PEPSetType(pep,type);
127:     } else if (!((PetscObject)pep)->type_name) {
128:       PEPSetType(pep,PEPTOAR);
129:     }

131:     PetscOptionsBoolGroupBegin("-pep_general","General polynomial eigenvalue problem","PEPSetProblemType",&flg);
132:     if (flg) { PEPSetProblemType(pep,PEP_GENERAL); }
133:     PetscOptionsBoolGroup("-pep_hermitian","Hermitian polynomial eigenvalue problem","PEPSetProblemType",&flg);
134:     if (flg) { PEPSetProblemType(pep,PEP_HERMITIAN); }
135:     PetscOptionsBoolGroup("-pep_hyperbolic","Hyperbolic polynomial eigenvalue problem","PEPSetProblemType",&flg);
136:     if (flg) { PEPSetProblemType(pep,PEP_HYPERBOLIC); }
137:     PetscOptionsBoolGroupEnd("-pep_gyroscopic","Gyroscopic polynomial eigenvalue problem","PEPSetProblemType",&flg);
138:     if (flg) { PEPSetProblemType(pep,PEP_GYROSCOPIC); }

140:     scale = pep->scale;
141:     PetscOptionsEnum("-pep_scale","Scaling strategy","PEPSetScale",PEPScaleTypes,(PetscEnum)scale,(PetscEnum*)&scale,&flg1);
142:     r = pep->sfactor;
143:     PetscOptionsReal("-pep_scale_factor","Scale factor","PEPSetScale",pep->sfactor,&r,&flg2);
144:     if (!flg2 && r==1.0) r = PETSC_DEFAULT;
145:     j = pep->sits;
146:     PetscOptionsInt("-pep_scale_its","Number of iterations in diagonal scaling","PEPSetScale",pep->sits,&j,&flg3);
147:     t = pep->slambda;
148:     PetscOptionsReal("-pep_scale_lambda","Estimate of eigenvalue (modulus) for diagonal scaling","PEPSetScale",pep->slambda,&t,&flg4);
149:     if (flg1 || flg2 || flg3 || flg4) { PEPSetScale(pep,scale,r,NULL,NULL,j,t); }

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

153:     refine = pep->refine;
154:     PetscOptionsEnum("-pep_refine","Iterative refinement method","PEPSetRefine",PEPRefineTypes,(PetscEnum)refine,(PetscEnum*)&refine,&flg1);
155:     i = pep->npart;
156:     PetscOptionsInt("-pep_refine_partitions","Number of partitions of the communicator for iterative refinement","PEPSetRefine",pep->npart,&i,&flg2);
157:     r = pep->rtol;
158:     PetscOptionsReal("-pep_refine_tol","Tolerance for iterative refinement","PEPSetRefine",pep->rtol==PETSC_DEFAULT?SLEPC_DEFAULT_TOL/1000:pep->rtol,&r,&flg3);
159:     j = pep->rits;
160:     PetscOptionsInt("-pep_refine_its","Maximum number of iterations for iterative refinement","PEPSetRefine",pep->rits,&j,&flg4);
161:     scheme = pep->scheme;
162:     PetscOptionsEnum("-pep_refine_scheme","Scheme used for linear systems within iterative refinement","PEPSetRefine",PEPRefineSchemes,(PetscEnum)scheme,(PetscEnum*)&scheme,&flg5);
163:     if (flg1 || flg2 || flg3 || flg4 || flg5) { PEPSetRefine(pep,refine,i,r,j,scheme); }

165:     i = pep->max_it? pep->max_it: PETSC_DEFAULT;
166:     PetscOptionsInt("-pep_max_it","Maximum number of iterations","PEPSetTolerances",pep->max_it,&i,&flg1);
167:     r = pep->tol;
168:     PetscOptionsReal("-pep_tol","Tolerance","PEPSetTolerances",pep->tol==PETSC_DEFAULT?SLEPC_DEFAULT_TOL:pep->tol,&r,&flg2);
169:     if (flg1 || flg2) { PEPSetTolerances(pep,r,i); }

171:     PetscOptionsBoolGroupBegin("-pep_conv_rel","Relative error convergence test","PEPSetConvergenceTest",&flg);
172:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_REL); }
173:     PetscOptionsBoolGroup("-pep_conv_norm","Convergence test relative to the matrix norms","PEPSetConvergenceTest",&flg);
174:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_NORM); }
175:     PetscOptionsBoolGroup("-pep_conv_abs","Absolute error convergence test","PEPSetConvergenceTest",&flg);
176:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_ABS); }
177:     PetscOptionsBoolGroupEnd("-pep_conv_user","User-defined convergence test","PEPSetConvergenceTest",&flg);
178:     if (flg) { PEPSetConvergenceTest(pep,PEP_CONV_USER); }

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

185:     i = pep->nev;
186:     PetscOptionsInt("-pep_nev","Number of eigenvalues to compute","PEPSetDimensions",pep->nev,&i,&flg1);
187:     j = pep->ncv? pep->ncv: PETSC_DEFAULT;
188:     PetscOptionsInt("-pep_ncv","Number of basis vectors","PEPSetDimensions",pep->ncv,&j,&flg2);
189:     k = pep->mpd? pep->mpd: PETSC_DEFAULT;
190:     PetscOptionsInt("-pep_mpd","Maximum dimension of projected problem","PEPSetDimensions",pep->mpd,&k,&flg3);
191:     if (flg1 || flg2 || flg3) { PEPSetDimensions(pep,i,j,k); }

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

195:     PetscOptionsBoolGroupBegin("-pep_largest_magnitude","Compute largest eigenvalues in magnitude","PEPSetWhichEigenpairs",&flg);
196:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_LARGEST_MAGNITUDE); }
197:     PetscOptionsBoolGroup("-pep_smallest_magnitude","Compute smallest eigenvalues in magnitude","PEPSetWhichEigenpairs",&flg);
198:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_SMALLEST_MAGNITUDE); }
199:     PetscOptionsBoolGroup("-pep_largest_real","Compute eigenvalues with largest real parts","PEPSetWhichEigenpairs",&flg);
200:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_LARGEST_REAL); }
201:     PetscOptionsBoolGroup("-pep_smallest_real","Compute eigenvalues with smallest real parts","PEPSetWhichEigenpairs",&flg);
202:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_SMALLEST_REAL); }
203:     PetscOptionsBoolGroup("-pep_largest_imaginary","Compute eigenvalues with largest imaginary parts","PEPSetWhichEigenpairs",&flg);
204:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_LARGEST_IMAGINARY); }
205:     PetscOptionsBoolGroup("-pep_smallest_imaginary","Compute eigenvalues with smallest imaginary parts","PEPSetWhichEigenpairs",&flg);
206:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_SMALLEST_IMAGINARY); }
207:     PetscOptionsBoolGroup("-pep_target_magnitude","Compute eigenvalues closest to target","PEPSetWhichEigenpairs",&flg);
208:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_TARGET_MAGNITUDE); }
209:     PetscOptionsBoolGroup("-pep_target_real","Compute eigenvalues with real parts closest to target","PEPSetWhichEigenpairs",&flg);
210:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_TARGET_REAL); }
211:     PetscOptionsBoolGroupEnd("-pep_target_imaginary","Compute eigenvalues with imaginary parts closest to target","PEPSetWhichEigenpairs",&flg);
212:     if (flg) { PEPSetWhichEigenpairs(pep,PEP_TARGET_IMAGINARY); }

214:     PetscOptionsScalar("-pep_target","Value of the target","PEPSetTarget",pep->target,&s,&flg);
215:     if (flg) {
216:       if (pep->which!=PEP_TARGET_REAL && pep->which!=PEP_TARGET_IMAGINARY) {
217:         PEPSetWhichEigenpairs(pep,PEP_TARGET_MAGNITUDE);
218:       }
219:       PEPSetTarget(pep,s);
220:     }

222:     k = 2;
223:     PetscOptionsRealArray("-pep_interval","Computational interval (two real values separated with a comma without spaces)","PEPSetInterval",array,&k,&flg);
224:     if (flg) {
225:       if (k<2) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_SIZ,"Must pass two values in -pep_interval (comma-separated without spaces)");
226:       PEPSetWhichEigenpairs(pep,PEP_ALL);
227:       PEPSetInterval(pep,array[0],array[1]);
228:     }

230:     /* -----------------------------------------------------------------------*/
231:     /*
232:       Cancels all monitors hardwired into code before call to PEPSetFromOptions()
233:     */
234:     PetscOptionsBool("-pep_monitor_cancel","Remove any hardwired monitor routines","PEPMonitorCancel",PETSC_FALSE,&flg,&set);
235:     if (set && flg) {
236:       PEPMonitorCancel(pep);
237:     }
238:     /*
239:       Text monitors
240:     */
241:     PEPMonitorSetFromOptions(pep,"-pep_monitor","Monitor first unconverged approximate eigenvalue and error estimate","PEPMonitorFirst",PEPMonitorFirst,PETSC_FALSE);
242:     PEPConvMonitorSetFromOptions(pep,"-pep_monitor_conv","Monitor approximate eigenvalues and error estimates as they converge","PEPMonitorConverged",PEPMonitorConverged);
243:     PEPMonitorSetFromOptions(pep,"-pep_monitor_all","Monitor approximate eigenvalues and error estimates","PEPMonitorAll",PEPMonitorAll,PETSC_TRUE);
244:     /*
245:       Line graph monitors
246:     */
247:     PetscOptionsBool("-pep_monitor_lg","Monitor first unconverged approximate error estimate graphically","PEPMonitorSet",PETSC_FALSE,&flg,&set);
248:     if (set && flg) {
249:       PEPMonitorLGCreate(PetscObjectComm((PetscObject)pep),NULL,"Error estimates",PETSC_DECIDE,PETSC_DECIDE,300,300,&lg);
250:       PEPMonitorSet(pep,PEPMonitorLG,lg,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
251:     }
252:     PetscOptionsBool("-pep_monitor_lg_all","Monitor error estimates graphically","PEPMonitorSet",PETSC_FALSE,&flg,&set);
253:     if (set && flg) {
254:       PEPMonitorLGCreate(PetscObjectComm((PetscObject)pep),NULL,"Error estimates",PETSC_DECIDE,PETSC_DECIDE,300,300,&lg);
255:       PEPMonitorSet(pep,PEPMonitorLGAll,lg,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
256:       PEPSetTrackAll(pep,PETSC_TRUE);
257:     }

259:     /* -----------------------------------------------------------------------*/
260:     PetscOptionsName("-pep_view","Print detailed information on solver used","PEPView",NULL);
261:     PetscOptionsName("-pep_view_vectors","View computed eigenvectors","PEPVectorsView",NULL);
262:     PetscOptionsName("-pep_view_values","View computed eigenvalues","PEPValuesView",NULL);
263:     PetscOptionsName("-pep_converged_reason","Print reason for convergence, and number of iterations","PEPReasonView",NULL);
264:     PetscOptionsName("-pep_error_absolute","Print absolute errors of each eigenpair","PEPErrorView",NULL);
265:     PetscOptionsName("-pep_error_relative","Print relative errors of each eigenpair","PEPErrorView",NULL);
266:     PetscOptionsName("-pep_error_backward","Print backward errors of each eigenpair","PEPErrorView",NULL);

268:     if (pep->ops->setfromoptions) {
269:       (*pep->ops->setfromoptions)(PetscOptionsObject,pep);
270:     }
271:     PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)pep);
272:   PetscOptionsEnd();

274:   if (!pep->V) { PEPGetBV(pep,&pep->V); }
275:   BVSetFromOptions(pep->V);
276:   if (!pep->rg) { PEPGetRG(pep,&pep->rg); }
277:   RGSetFromOptions(pep->rg);
278:   if (!pep->ds) { PEPGetDS(pep,&pep->ds); }
279:   DSSetFromOptions(pep->ds);
280:   if (!pep->st) { PEPGetST(pep,&pep->st); }
281:   PEPSetDefaultST(pep);
282:   STSetFromOptions(pep->st);
283:   if (!pep->refineksp) { PEPRefineGetKSP(pep,&pep->refineksp); }
284:   KSPSetFromOptions(pep->refineksp);
285:   return(0);
286: }

288: /*@C
289:    PEPGetTolerances - Gets the tolerance and maximum iteration count used
290:    by the PEP convergence tests.

292:    Not Collective

294:    Input Parameter:
295: .  pep - the polynomial eigensolver context

297:    Output Parameters:
298: +  tol - the convergence tolerance
299: -  maxits - maximum number of iterations

301:    Notes:
302:    The user can specify NULL for any parameter that is not needed.

304:    Level: intermediate

306: .seealso: PEPSetTolerances()
307: @*/
308: PetscErrorCode PEPGetTolerances(PEP pep,PetscReal *tol,PetscInt *maxits)
309: {
312:   if (tol)    *tol    = pep->tol;
313:   if (maxits) *maxits = pep->max_it;
314:   return(0);
315: }

317: /*@
318:    PEPSetTolerances - Sets the tolerance and maximum iteration count used
319:    by the PEP convergence tests.

321:    Logically Collective on PEP

323:    Input Parameters:
324: +  pep - the polynomial eigensolver context
325: .  tol - the convergence tolerance
326: -  maxits - maximum number of iterations to use

328:    Options Database Keys:
329: +  -pep_tol <tol> - Sets the convergence tolerance
330: -  -pep_max_it <maxits> - Sets the maximum number of iterations allowed

332:    Notes:
333:    Use PETSC_DEFAULT for either argument to assign a reasonably good value.

335:    Level: intermediate

337: .seealso: PEPGetTolerances()
338: @*/
339: PetscErrorCode PEPSetTolerances(PEP pep,PetscReal tol,PetscInt maxits)
340: {
345:   if (tol == PETSC_DEFAULT) {
346:     pep->tol   = PETSC_DEFAULT;
347:     pep->state = PEP_STATE_INITIAL;
348:   } else {
349:     if (tol <= 0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of tol. Must be > 0");
350:     pep->tol = tol;
351:   }
352:   if (maxits == PETSC_DEFAULT || maxits == PETSC_DECIDE) {
353:     pep->max_it = 0;
354:     pep->state  = PEP_STATE_INITIAL;
355:   } else {
356:     if (maxits <= 0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of maxits. Must be > 0");
357:     pep->max_it = maxits;
358:   }
359:   return(0);
360: }

362: /*@C
363:    PEPGetDimensions - Gets the number of eigenvalues to compute
364:    and the dimension of the subspace.

366:    Not Collective

368:    Input Parameter:
369: .  pep - the polynomial eigensolver context

371:    Output Parameters:
372: +  nev - number of eigenvalues to compute
373: .  ncv - the maximum dimension of the subspace to be used by the solver
374: -  mpd - the maximum dimension allowed for the projected problem

376:    Notes:
377:    The user can specify NULL for any parameter that is not needed.

379:    Level: intermediate

381: .seealso: PEPSetDimensions()
382: @*/
383: PetscErrorCode PEPGetDimensions(PEP pep,PetscInt *nev,PetscInt *ncv,PetscInt *mpd)
384: {
387:   if (nev) *nev = pep->nev;
388:   if (ncv) *ncv = pep->ncv;
389:   if (mpd) *mpd = pep->mpd;
390:   return(0);
391: }

393: /*@
394:    PEPSetDimensions - Sets the number of eigenvalues to compute
395:    and the dimension of the subspace.

397:    Logically Collective on PEP

399:    Input Parameters:
400: +  pep - the polynomial eigensolver context
401: .  nev - number of eigenvalues to compute
402: .  ncv - the maximum dimension of the subspace to be used by the solver
403: -  mpd - the maximum dimension allowed for the projected problem

405:    Options Database Keys:
406: +  -pep_nev <nev> - Sets the number of eigenvalues
407: .  -pep_ncv <ncv> - Sets the dimension of the subspace
408: -  -pep_mpd <mpd> - Sets the maximum projected dimension

410:    Notes:
411:    Use PETSC_DEFAULT for ncv and mpd to assign a reasonably good value, which is
412:    dependent on the solution method.

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

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

423:    Level: intermediate

425: .seealso: PEPGetDimensions()
426: @*/
427: PetscErrorCode PEPSetDimensions(PEP pep,PetscInt nev,PetscInt ncv,PetscInt mpd)
428: {
434:   if (nev<1) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of nev. Must be > 0");
435:   pep->nev = nev;
436:   if (ncv == PETSC_DECIDE || ncv == PETSC_DEFAULT) {
437:     pep->ncv = 0;
438:   } else {
439:     if (ncv<1) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of ncv. Must be > 0");
440:     pep->ncv = ncv;
441:   }
442:   if (mpd == PETSC_DECIDE || mpd == PETSC_DEFAULT) {
443:     pep->mpd = 0;
444:   } else {
445:     if (mpd<1) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of mpd. Must be > 0");
446:     pep->mpd = mpd;
447:   }
448:   pep->state = PEP_STATE_INITIAL;
449:   return(0);
450: }

452: /*@
453:    PEPSetWhichEigenpairs - Specifies which portion of the spectrum is
454:    to be sought.

456:    Logically Collective on PEP

458:    Input Parameters:
459: +  pep   - eigensolver context obtained from PEPCreate()
460: -  which - the portion of the spectrum to be sought

462:    Possible values:
463:    The parameter 'which' can have one of these values

465: +     PEP_LARGEST_MAGNITUDE - largest eigenvalues in magnitude (default)
466: .     PEP_SMALLEST_MAGNITUDE - smallest eigenvalues in magnitude
467: .     PEP_LARGEST_REAL - largest real parts
468: .     PEP_SMALLEST_REAL - smallest real parts
469: .     PEP_LARGEST_IMAGINARY - largest imaginary parts
470: .     PEP_SMALLEST_IMAGINARY - smallest imaginary parts
471: .     PEP_TARGET_MAGNITUDE - eigenvalues closest to the target (in magnitude)
472: .     PEP_TARGET_REAL - eigenvalues with real part closest to target
473: .     PEP_TARGET_IMAGINARY - eigenvalues with imaginary part closest to target
474: -     PEP_WHICH_USER - user defined ordering set with PEPSetEigenvalueComparison()

476:    Options Database Keys:
477: +   -pep_largest_magnitude - Sets largest eigenvalues in magnitude
478: .   -pep_smallest_magnitude - Sets smallest eigenvalues in magnitude
479: .   -pep_largest_real - Sets largest real parts
480: .   -pep_smallest_real - Sets smallest real parts
481: .   -pep_largest_imaginary - Sets largest imaginary parts
482: .   -pep_smallest_imaginary - Sets smallest imaginary parts
483: .   -pep_target_magnitude - Sets eigenvalues closest to target
484: .   -pep_target_real - Sets real parts closest to target
485: -   -pep_target_imaginary - Sets imaginary parts closest to target

487:    Notes:
488:    Not all eigensolvers implemented in PEP account for all the possible values
489:    stated above. If SLEPc is compiled for real numbers PEP_LARGEST_IMAGINARY
490:    and PEP_SMALLEST_IMAGINARY use the absolute value of the imaginary part
491:    for eigenvalue selection.

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

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

498:    Level: intermediate

500: .seealso: PEPGetWhichEigenpairs(), PEPSetTarget(), PEPSetEigenvalueComparison(), PEPWhich
501: @*/
502: PetscErrorCode PEPSetWhichEigenpairs(PEP pep,PEPWhich which)
503: {
507:   switch (which) {
508:     case PEP_LARGEST_MAGNITUDE:
509:     case PEP_SMALLEST_MAGNITUDE:
510:     case PEP_LARGEST_REAL:
511:     case PEP_SMALLEST_REAL:
512:     case PEP_LARGEST_IMAGINARY:
513:     case PEP_SMALLEST_IMAGINARY:
514:     case PEP_TARGET_MAGNITUDE:
515:     case PEP_TARGET_REAL:
516: #if defined(PETSC_USE_COMPLEX)
517:     case PEP_TARGET_IMAGINARY:
518: #endif
519:     case PEP_ALL:
520:     case PEP_WHICH_USER:
521:       if (pep->which != which) {
522:         pep->state = PEP_STATE_INITIAL;
523:         pep->which = which;
524:       }
525:       break;
526:     default:
527:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'which' value");
528:   }
529:   return(0);
530: }

532: /*@
533:     PEPGetWhichEigenpairs - Returns which portion of the spectrum is to be
534:     sought.

536:     Not Collective

538:     Input Parameter:
539: .   pep - eigensolver context obtained from PEPCreate()

541:     Output Parameter:
542: .   which - the portion of the spectrum to be sought

544:     Notes:
545:     See PEPSetWhichEigenpairs() for possible values of 'which'.

547:     Level: intermediate

549: .seealso: PEPSetWhichEigenpairs(), PEPWhich
550: @*/
551: PetscErrorCode PEPGetWhichEigenpairs(PEP pep,PEPWhich *which)
552: {
556:   *which = pep->which;
557:   return(0);
558: }

560: /*@C
561:    PEPSetEigenvalueComparison - Specifies the eigenvalue comparison function
562:    when PEPSetWhichEigenpairs() is set to PEP_WHICH_USER.

564:    Logically Collective on PEP

566:    Input Parameters:
567: +  pep  - eigensolver context obtained from PEPCreate()
568: .  func - a pointer to the comparison function
569: -  ctx  - a context pointer (the last parameter to the comparison function)

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

574: +   ar     - real part of the 1st eigenvalue
575: .   ai     - imaginary part of the 1st eigenvalue
576: .   br     - real part of the 2nd eigenvalue
577: .   bi     - imaginary part of the 2nd eigenvalue
578: .   res    - result of comparison
579: -   ctx    - optional context, as set by PEPSetEigenvalueComparison()

581:    Note:
582:    The returning parameter 'res' can be
583: +  negative - if the 1st eigenvalue is preferred to the 2st one
584: .  zero     - if both eigenvalues are equally preferred
585: -  positive - if the 2st eigenvalue is preferred to the 1st one

587:    Level: advanced

589: .seealso: PEPSetWhichEigenpairs(), PEPWhich
590: @*/
591: PetscErrorCode PEPSetEigenvalueComparison(PEP pep,PetscErrorCode (*func)(PetscScalar,PetscScalar,PetscScalar,PetscScalar,PetscInt*,void*),void* ctx)
592: {
595:   pep->sc->comparison    = func;
596:   pep->sc->comparisonctx = ctx;
597:   pep->which             = PEP_WHICH_USER;
598:   return(0);
599: }

601: /*@
602:    PEPSetProblemType - Specifies the type of the polynomial eigenvalue problem.

604:    Logically Collective on PEP

606:    Input Parameters:
607: +  pep  - the polynomial eigensolver context
608: -  type - a known type of polynomial eigenvalue problem

610:    Options Database Keys:
611: +  -pep_general - general problem with no particular structure
612: .  -pep_hermitian - problem whose coefficient matrices are Hermitian
613: .  -pep_hyperbolic - Hermitian problem that satisfies the definition of hyperbolic
614: -  -pep_gyroscopic - problem with Hamiltonian structure

616:    Notes:
617:    Allowed values for the problem type are: general (PEP_GENERAL), Hermitian
618:    (PEP_HERMITIAN), hyperbolic (PEP_HYPERBOLIC), and gyroscopic (PEP_GYROSCOPIC).

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

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

629:    Level: intermediate

631: .seealso: PEPSetOperators(), PEPSetType(), PEPGetProblemType(), PEPProblemType
632: @*/
633: PetscErrorCode PEPSetProblemType(PEP pep,PEPProblemType type)
634: {
638:   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");
639:   if (type != pep->problem_type) {
640:     pep->problem_type = type;
641:     pep->state = PEP_STATE_INITIAL;
642:   }
643:   return(0);
644: }

646: /*@
647:    PEPGetProblemType - Gets the problem type from the PEP object.

649:    Not Collective

651:    Input Parameter:
652: .  pep - the polynomial eigensolver context

654:    Output Parameter:
655: .  type - the problem type

657:    Level: intermediate

659: .seealso: PEPSetProblemType(), PEPProblemType
660: @*/
661: PetscErrorCode PEPGetProblemType(PEP pep,PEPProblemType *type)
662: {
666:   *type = pep->problem_type;
667:   return(0);
668: }

670: /*@
671:    PEPSetBasis - Specifies the type of polynomial basis used to describe the
672:    polynomial eigenvalue problem.

674:    Logically Collective on PEP

676:    Input Parameters:
677: +  pep   - the polynomial eigensolver context
678: -  basis - the type of polynomial basis

680:    Options Database Key:
681: .  -pep_basis <basis> - Select the basis type

683:    Notes:
684:    By default, the coefficient matrices passed via PEPSetOperators() are
685:    expressed in the monomial basis, i.e.
686:    P(lambda) = A_0 + lambda*A_1 + lambda^2*A_2 + ... + lambda^d*A_d.
687:    Other polynomial bases may have better numerical behaviour, but the user
688:    must then pass the coefficient matrices accordingly.

690:    Level: intermediate

692: .seealso: PEPSetOperators(), PEPGetBasis(), PEPBasis
693: @*/
694: PetscErrorCode PEPSetBasis(PEP pep,PEPBasis basis)
695: {
699:   pep->basis = basis;
700:   return(0);
701: }

703: /*@
704:    PEPGetBasis - Gets the type of polynomial basis from the PEP object.

706:    Not Collective

708:    Input Parameter:
709: .  pep - the polynomial eigensolver context

711:    Output Parameter:
712: .  basis - the polynomial basis

714:    Level: intermediate

716: .seealso: PEPSetBasis(), PEPBasis
717: @*/
718: PetscErrorCode PEPGetBasis(PEP pep,PEPBasis *basis)
719: {
723:   *basis = pep->basis;
724:   return(0);
725: }

727: /*@
728:    PEPSetTrackAll - Specifies if the solver must compute the residual of all
729:    approximate eigenpairs or not.

731:    Logically Collective on PEP

733:    Input Parameters:
734: +  pep      - the eigensolver context
735: -  trackall - whether compute all residuals or not

737:    Notes:
738:    If the user sets trackall=PETSC_TRUE then the solver explicitly computes
739:    the residual for each eigenpair approximation. Computing the residual is
740:    usually an expensive operation and solvers commonly compute the associated
741:    residual to the first unconverged eigenpair.
742:    The options '-pep_monitor_all' and '-pep_monitor_lg_all' automatically
743:    activate this option.

745:    Level: developer

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

758: /*@
759:    PEPGetTrackAll - Returns the flag indicating whether all residual norms must
760:    be computed or not.

762:    Not Collective

764:    Input Parameter:
765: .  pep - the eigensolver context

767:    Output Parameter:
768: .  trackall - the returned flag

770:    Level: developer

772: .seealso: PEPSetTrackAll()
773: @*/
774: PetscErrorCode PEPGetTrackAll(PEP pep,PetscBool *trackall)
775: {
779:   *trackall = pep->trackall;
780:   return(0);
781: }

783: /*@C
784:    PEPSetConvergenceTestFunction - Sets a function to compute the error estimate
785:    used in the convergence test.

787:    Logically Collective on PEP

789:    Input Parameters:
790: +  pep     - eigensolver context obtained from PEPCreate()
791: .  func    - a pointer to the convergence test function
792: .  ctx     - context for private data for the convergence routine (may be null)
793: -  destroy - a routine for destroying the context (may be null)

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

798: +   pep    - eigensolver context obtained from PEPCreate()
799: .   eigr   - real part of the eigenvalue
800: .   eigi   - imaginary part of the eigenvalue
801: .   res    - residual norm associated to the eigenpair
802: .   errest - (output) computed error estimate
803: -   ctx    - optional context, as set by PEPSetConvergenceTestFunction()

805:    Note:
806:    If the error estimate returned by the convergence test function is less than
807:    the tolerance, then the eigenvalue is accepted as converged.

809:    Level: advanced

811: .seealso: PEPSetConvergenceTest(), PEPSetTolerances()
812: @*/
813: PetscErrorCode PEPSetConvergenceTestFunction(PEP pep,PetscErrorCode (*func)(PEP,PetscScalar,PetscScalar,PetscReal,PetscReal*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
814: {

819:   if (pep->convergeddestroy) {
820:     (*pep->convergeddestroy)(pep->convergedctx);
821:   }
822:   pep->convergeduser    = func;
823:   pep->convergeddestroy = destroy;
824:   pep->convergedctx     = ctx;
825:   if (func == PEPConvergedRelative) pep->conv = PEP_CONV_REL;
826:   else if (func == PEPConvergedNorm) pep->conv = PEP_CONV_NORM;
827:   else if (func == PEPConvergedAbsolute) pep->conv = PEP_CONV_ABS;
828:   else {
829:     pep->conv      = PEP_CONV_USER;
830:     pep->converged = pep->convergeduser;
831:   }
832:   return(0);
833: }

835: /*@
836:    PEPSetConvergenceTest - Specifies how to compute the error estimate
837:    used in the convergence test.

839:    Logically Collective on PEP

841:    Input Parameters:
842: +  pep  - eigensolver context obtained from PEPCreate()
843: -  conv - the type of convergence test

845:    Options Database Keys:
846: +  -pep_conv_abs    - Sets the absolute convergence test
847: .  -pep_conv_rel    - Sets the convergence test relative to the eigenvalue
848: .  -pep_conv_norm   - Sets the convergence test relative to the matrix norms
849: -  -pep_conv_user   - Selects the user-defined convergence test

851:    Note:
852:    The parameter 'conv' can have one of these values
853: +     PEP_CONV_ABS    - absolute error ||r||
854: .     PEP_CONV_REL    - error relative to the eigenvalue l, ||r||/|l|
855: .     PEP_CONV_NORM   - error relative matrix norms, ||r||/sum_i(l^i*||A_i||)
856: -     PEP_CONV_USER   - function set by PEPSetConvergenceTestFunction()

858:    Level: intermediate

860: .seealso: PEPGetConvergenceTest(), PEPSetConvergenceTestFunction(), PEPSetStoppingTest(), PEPConv
861: @*/
862: PetscErrorCode PEPSetConvergenceTest(PEP pep,PEPConv conv)
863: {
867:   switch (conv) {
868:     case PEP_CONV_ABS:  pep->converged = PEPConvergedAbsolute; break;
869:     case PEP_CONV_REL:  pep->converged = PEPConvergedRelative; break;
870:     case PEP_CONV_NORM: pep->converged = PEPConvergedNorm; break;
871:     case PEP_CONV_USER:
872:       if (!pep->convergeduser) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ORDER,"Must call PEPSetConvergenceTestFunction() first");
873:       pep->converged = pep->convergeduser;
874:       break;
875:     default:
876:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'conv' value");
877:   }
878:   pep->conv = conv;
879:   return(0);
880: }

882: /*@
883:    PEPGetConvergenceTest - Gets the method used to compute the error estimate
884:    used in the convergence test.

886:    Not Collective

888:    Input Parameters:
889: .  pep   - eigensolver context obtained from PEPCreate()

891:    Output Parameters:
892: .  conv  - the type of convergence test

894:    Level: intermediate

896: .seealso: PEPSetConvergenceTest(), PEPConv
897: @*/
898: PetscErrorCode PEPGetConvergenceTest(PEP pep,PEPConv *conv)
899: {
903:   *conv = pep->conv;
904:   return(0);
905: }

907: /*@C
908:    PEPSetStoppingTestFunction - Sets a function to decide when to stop the outer
909:    iteration of the eigensolver.

911:    Logically Collective on PEP

913:    Input Parameters:
914: +  pep     - eigensolver context obtained from PEPCreate()
915: .  func    - pointer to the stopping test function
916: .  ctx     - context for private data for the stopping routine (may be null)
917: -  destroy - a routine for destroying the context (may be null)

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

922: +   pep    - eigensolver context obtained from PEPCreate()
923: .   its    - current number of iterations
924: .   max_it - maximum number of iterations
925: .   nconv  - number of currently converged eigenpairs
926: .   nev    - number of requested eigenpairs
927: .   reason - (output) result of the stopping test
928: -   ctx    - optional context, as set by PEPSetStoppingTestFunction()

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

936:    Level: advanced

938: .seealso: PEPSetStoppingTest(), PEPStoppingBasic()
939: @*/
940: PetscErrorCode PEPSetStoppingTestFunction(PEP pep,PetscErrorCode (*func)(PEP,PetscInt,PetscInt,PetscInt,PetscInt,PEPConvergedReason*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
941: {

946:   if (pep->stoppingdestroy) {
947:     (*pep->stoppingdestroy)(pep->stoppingctx);
948:   }
949:   pep->stoppinguser    = func;
950:   pep->stoppingdestroy = destroy;
951:   pep->stoppingctx     = ctx;
952:   if (func == PEPStoppingBasic) pep->stop = PEP_STOP_BASIC;
953:   else {
954:     pep->stop     = PEP_STOP_USER;
955:     pep->stopping = pep->stoppinguser;
956:   }
957:   return(0);
958: }

960: /*@
961:    PEPSetStoppingTest - Specifies how to decide the termination of the outer
962:    loop of the eigensolver.

964:    Logically Collective on PEP

966:    Input Parameters:
967: +  pep  - eigensolver context obtained from PEPCreate()
968: -  stop - the type of stopping test

970:    Options Database Keys:
971: +  -pep_stop_basic - Sets the default stopping test
972: -  -pep_stop_user  - Selects the user-defined stopping test

974:    Note:
975:    The parameter 'stop' can have one of these values
976: +     PEP_STOP_BASIC - default stopping test
977: -     PEP_STOP_USER  - function set by PEPSetStoppingTestFunction()

979:    Level: advanced

981: .seealso: PEPGetStoppingTest(), PEPSetStoppingTestFunction(), PEPSetConvergenceTest(), PEPStop
982: @*/
983: PetscErrorCode PEPSetStoppingTest(PEP pep,PEPStop stop)
984: {
988:   switch (stop) {
989:     case PEP_STOP_BASIC: pep->stopping = PEPStoppingBasic; break;
990:     case PEP_STOP_USER:
991:       if (!pep->stoppinguser) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ORDER,"Must call PEPSetStoppingTestFunction() first");
992:       pep->stopping = pep->stoppinguser;
993:       break;
994:     default:
995:       SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'stop' value");
996:   }
997:   pep->stop = stop;
998:   return(0);
999: }

1001: /*@
1002:    PEPGetStoppingTest - Gets the method used to decide the termination of the outer
1003:    loop of the eigensolver.

1005:    Not Collective

1007:    Input Parameters:
1008: .  pep   - eigensolver context obtained from PEPCreate()

1010:    Output Parameters:
1011: .  stop  - the type of stopping test

1013:    Level: advanced

1015: .seealso: PEPSetStoppingTest(), PEPStop
1016: @*/
1017: PetscErrorCode PEPGetStoppingTest(PEP pep,PEPStop *stop)
1018: {
1022:   *stop = pep->stop;
1023:   return(0);
1024: }

1026: /*@C
1027:    PEPSetScale - Specifies the scaling strategy to be used.

1029:    Logically Collective on PEP

1031:    Input Parameters:
1032: +  pep    - the eigensolver context
1033: .  scale  - scaling strategy
1034: .  alpha  - the scaling factor used in the scalar strategy
1035: .  Dl     - the left diagonal matrix of the diagonal scaling algorithm
1036: .  Dr     - the right diagonal matrix of the diagonal scaling algorithm
1037: .  its    - number of iterations of the diagonal scaling algorithm
1038: -  lambda - approximation to wanted eigenvalues (modulus)

1040:    Options Database Keys:
1041: +  -pep_scale <type> - scaling type, one of <none,scalar,diagonal,both>
1042: .  -pep_scale_factor <alpha> - the scaling factor
1043: .  -pep_scale_its <its> - number of iterations
1044: -  -pep_scale_lambda <lambda> - approximation to eigenvalues

1046:    Notes:
1047:    There are two non-exclusive scaling strategies: scalar and diagonal.

1049:    In the scalar strategy, scaling is applied to the eigenvalue, that is,
1050:    mu = lambda/alpha is the new eigenvalue and all matrices are scaled
1051:    accordingly. After solving the scaled problem, the original lambda is
1052:    recovered. Parameter 'alpha' must be positive. Use PETSC_DECIDE to let
1053:    the solver compute a reasonable scaling factor.

1055:    In the diagonal strategy, the solver works implicitly with matrix Dl*A*Dr,
1056:    where Dl and Dr are appropriate diagonal matrices. This improves the accuracy
1057:    of the computed results in some cases. The user may provide the Dr and Dl
1058:    matrices represented as Vec objects storing diagonal elements. If not
1059:    provided, these matrices are computed internally. This option requires
1060:    that the polynomial coefficient matrices are of MATAIJ type.
1061:    The parameter 'its' is the number of iterations performed by the method.
1062:    Parameter 'lambda' must be positive. Use PETSC_DECIDE or set lambda = 1.0 if
1063:    no information about eigenvalues is available.

1065:    Level: intermediate

1067: .seealso: PEPGetScale()
1068: @*/
1069: PetscErrorCode PEPSetScale(PEP pep,PEPScale scale,PetscReal alpha,Vec Dl,Vec Dr,PetscInt its,PetscReal lambda)
1070: {

1076:   pep->scale = scale;
1077:   if (scale==PEP_SCALE_SCALAR || scale==PEP_SCALE_BOTH) {
1079:     if (alpha == PETSC_DEFAULT || alpha == PETSC_DECIDE) {
1080:       pep->sfactor = 0.0;
1081:       pep->sfactor_set = PETSC_FALSE;
1082:     } else {
1083:       if (alpha<=0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of alpha. Must be > 0");
1084:       pep->sfactor = alpha;
1085:       pep->sfactor_set = PETSC_TRUE;
1086:     }
1087:   }
1088:   if (scale==PEP_SCALE_DIAGONAL || scale==PEP_SCALE_BOTH) {
1089:     if (Dl) {
1092:       PetscObjectReference((PetscObject)Dl);
1093:       VecDestroy(&pep->Dl);
1094:       pep->Dl = Dl;
1095:     }
1096:     if (Dr) {
1099:       PetscObjectReference((PetscObject)Dr);
1100:       VecDestroy(&pep->Dr);
1101:       pep->Dr = Dr;
1102:     }
1105:     if (its==PETSC_DECIDE || its==PETSC_DEFAULT) pep->sits = 5;
1106:     else pep->sits = its;
1107:     if (lambda==PETSC_DECIDE || lambda==PETSC_DEFAULT) pep->slambda = 1.0;
1108:     else if (lambda<=0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of lambda. Must be > 0");
1109:     else pep->slambda = lambda;
1110:   }
1111:   pep->state = PEP_STATE_INITIAL;
1112:   return(0);
1113: }

1115: /*@C
1116:    PEPGetScale - Gets the scaling strategy used by the PEP object, and the
1117:    associated parameters.

1119:    Not Collectiv, but vectors are shared by all processors that share the PEP

1121:    Input Parameter:
1122: .  pep - the eigensolver context

1124:    Output Parameters:
1125: +  scale  - scaling strategy
1126: .  alpha  - the scaling factor used in the scalar strategy
1127: .  Dl     - the left diagonal matrix of the diagonal scaling algorithm
1128: .  Dr     - the right diagonal matrix of the diagonal scaling algorithm
1129: .  its    - number of iterations of the diagonal scaling algorithm
1130: -  lambda - approximation to wanted eigenvalues (modulus)

1132:    Level: intermediate

1134:    Note:
1135:    The user can specify NULL for any parameter that is not needed.

1137:    If Dl or Dr were not set by the user, then the ones computed internally are
1138:    returned (or a null pointer if called before PEPSetUp).

1140: .seealso: PEPSetScale(), PEPSetUp()
1141: @*/
1142: PetscErrorCode PEPGetScale(PEP pep,PEPScale *scale,PetscReal *alpha,Vec *Dl,Vec *Dr,PetscInt *its,PetscReal *lambda)
1143: {
1146:   if (scale)  *scale  = pep->scale;
1147:   if (alpha)  *alpha  = pep->sfactor;
1148:   if (Dl)     *Dl     = pep->Dl;
1149:   if (Dr)     *Dr     = pep->Dr;
1150:   if (its)    *its    = pep->sits;
1151:   if (lambda) *lambda = pep->slambda;
1152:   return(0);
1153: }

1155: /*@
1156:    PEPSetExtract - Specifies the extraction strategy to be used.

1158:    Logically Collective on PEP

1160:    Input Parameters:
1161: +  pep     - the eigensolver context
1162: -  extract - extraction strategy

1164:    Options Database Keys:
1165: .  -pep_extract <type> - extraction type, one of <none,norm,residual,structured>

1167:    Level: intermediate

1169: .seealso: PEPGetExtract()
1170: @*/
1171: PetscErrorCode PEPSetExtract(PEP pep,PEPExtract extract)
1172: {
1176:   pep->extract = extract;
1177:   return(0);
1178: }

1180: /*@
1181:    PEPGetExtract - Gets the extraction strategy used by the PEP object.

1183:    Not Collective

1185:    Input Parameter:
1186: .  pep - the eigensolver context

1188:    Output Parameter:
1189: .  extract - extraction strategy

1191:    Level: intermediate

1193: .seealso: PEPSetExtract()
1194: @*/
1195: PetscErrorCode PEPGetExtract(PEP pep,PEPExtract *extract)
1196: {
1199:   if (extract) *extract = pep->extract;
1200:   return(0);
1201: }

1203: /*@
1204:    PEPSetRefine - Specifies the refinement type (and options) to be used
1205:    after the solve.

1207:    Logically Collective on PEP

1209:    Input Parameters:
1210: +  pep    - the polynomial eigensolver context
1211: .  refine - refinement type
1212: .  npart  - number of partitions of the communicator
1213: .  tol    - the convergence tolerance
1214: .  its    - maximum number of refinement iterations
1215: -  scheme - which scheme to be used for solving the involved linear systems

1217:    Options Database Keys:
1218: +  -pep_refine <type> - refinement type, one of <none,simple,multiple>
1219: .  -pep_refine_partitions <n> - the number of partitions
1220: .  -pep_refine_tol <tol> - the tolerance
1221: .  -pep_refine_its <its> - number of iterations
1222: -  -pep_refine_scheme - to set the scheme for the linear solves

1224:    Notes:
1225:    By default, iterative refinement is disabled, since it may be very
1226:    costly. There are two possible refinement strategies: simple and multiple.
1227:    The simple approach performs iterative refinement on each of the
1228:    converged eigenpairs individually, whereas the multiple strategy works
1229:    with the invariant pair as a whole, refining all eigenpairs simultaneously.
1230:    The latter may be required for the case of multiple eigenvalues.

1232:    In some cases, especially when using direct solvers within the
1233:    iterative refinement method, it may be helpful for improved scalability
1234:    to split the communicator in several partitions. The npart parameter
1235:    indicates how many partitions to use (defaults to 1).

1237:    The tol and its parameters specify the stopping criterion. In the simple
1238:    method, refinement continues until the residual of each eigenpair is
1239:    below the tolerance (tol defaults to the PEP tol, but may be set to a
1240:    different value). In contrast, the multiple method simply performs its
1241:    refinement iterations (just one by default).

1243:    The scheme argument is used to change the way in which linear systems are
1244:    solved. Possible choices are: explicit, mixed block elimination (MBE),
1245:    and Schur complement.

1247:    Level: intermediate

1249: .seealso: PEPGetRefine()
1250: @*/
1251: PetscErrorCode PEPSetRefine(PEP pep,PEPRefine refine,PetscInt npart,PetscReal tol,PetscInt its,PEPRefineScheme scheme)
1252: {
1254:   PetscMPIInt    size;

1263:   pep->refine = refine;
1264:   if (refine) {  /* process parameters only if not REFINE_NONE */
1265:     if (npart!=pep->npart) {
1266:       PetscSubcommDestroy(&pep->refinesubc);
1267:       KSPDestroy(&pep->refineksp);
1268:     }
1269:     if (npart == PETSC_DEFAULT || npart == PETSC_DECIDE) {
1270:       pep->npart = 1;
1271:     } else {
1272:       MPI_Comm_size(PetscObjectComm((PetscObject)pep),&size);
1273:       if (npart<1 || npart>size) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of npart");
1274:       pep->npart = npart;
1275:     }
1276:     if (tol == PETSC_DEFAULT || tol == PETSC_DECIDE) {
1277:       pep->rtol = PETSC_DEFAULT;
1278:     } else {
1279:       if (tol<=0.0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of tol. Must be > 0");
1280:       pep->rtol = tol;
1281:     }
1282:     if (its==PETSC_DECIDE || its==PETSC_DEFAULT) {
1283:       pep->rits = PETSC_DEFAULT;
1284:     } else {
1285:       if (its<0) SETERRQ(PetscObjectComm((PetscObject)pep),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of its. Must be >= 0");
1286:       pep->rits = its;
1287:     }
1288:     pep->scheme = scheme;
1289:   }
1290:   pep->state = PEP_STATE_INITIAL;
1291:   return(0);
1292: }

1294: /*@C
1295:    PEPGetRefine - Gets the refinement strategy used by the PEP object, and the
1296:    associated parameters.

1298:    Not Collective

1300:    Input Parameter:
1301: .  pep - the polynomial eigensolver context

1303:    Output Parameters:
1304: +  refine - refinement type
1305: .  npart  - number of partitions of the communicator
1306: .  tol    - the convergence tolerance
1307: .  its    - maximum number of refinement iterations
1308: -  scheme - the scheme used for solving linear systems

1310:    Level: intermediate

1312:    Note:
1313:    The user can specify NULL for any parameter that is not needed.

1315: .seealso: PEPSetRefine()
1316: @*/
1317: PetscErrorCode PEPGetRefine(PEP pep,PEPRefine *refine,PetscInt *npart,PetscReal *tol,PetscInt *its,PEPRefineScheme *scheme)
1318: {
1321:   if (refine) *refine = pep->refine;
1322:   if (npart)  *npart  = pep->npart;
1323:   if (tol)    *tol    = pep->rtol;
1324:   if (its)    *its    = pep->rits;
1325:   if (scheme) *scheme = pep->scheme;
1326:   return(0);
1327: }

1329: /*@C
1330:    PEPSetOptionsPrefix - Sets the prefix used for searching for all
1331:    PEP options in the database.

1333:    Logically Collective on PEP

1335:    Input Parameters:
1336: +  pep - the polynomial eigensolver context
1337: -  prefix - the prefix string to prepend to all PEP option requests

1339:    Notes:
1340:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1341:    The first character of all runtime options is AUTOMATICALLY the
1342:    hyphen.

1344:    For example, to distinguish between the runtime options for two
1345:    different PEP contexts, one could call
1346: .vb
1347:       PEPSetOptionsPrefix(pep1,"qeig1_")
1348:       PEPSetOptionsPrefix(pep2,"qeig2_")
1349: .ve

1351:    Level: advanced

1353: .seealso: PEPAppendOptionsPrefix(), PEPGetOptionsPrefix()
1354: @*/
1355: PetscErrorCode PEPSetOptionsPrefix(PEP pep,const char *prefix)
1356: {

1361:   if (!pep->st) { PEPGetST(pep,&pep->st); }
1362:   STSetOptionsPrefix(pep->st,prefix);
1363:   if (!pep->V) { PEPGetBV(pep,&pep->V); }
1364:   BVSetOptionsPrefix(pep->V,prefix);
1365:   if (!pep->ds) { PEPGetDS(pep,&pep->ds); }
1366:   DSSetOptionsPrefix(pep->ds,prefix);
1367:   if (!pep->rg) { PEPGetRG(pep,&pep->rg); }
1368:   RGSetOptionsPrefix(pep->rg,prefix);
1369:   PetscObjectSetOptionsPrefix((PetscObject)pep,prefix);
1370:   return(0);
1371: }

1373: /*@C
1374:    PEPAppendOptionsPrefix - Appends to the prefix used for searching for all
1375:    PEP options in the database.

1377:    Logically Collective on PEP

1379:    Input Parameters:
1380: +  pep - the polynomial eigensolver context
1381: -  prefix - the prefix string to prepend to all PEP option requests

1383:    Notes:
1384:    A hyphen (-) must NOT be given at the beginning of the prefix name.
1385:    The first character of all runtime options is AUTOMATICALLY the hyphen.

1387:    Level: advanced

1389: .seealso: PEPSetOptionsPrefix(), PEPGetOptionsPrefix()
1390: @*/
1391: PetscErrorCode PEPAppendOptionsPrefix(PEP pep,const char *prefix)
1392: {

1397:   if (!pep->st) { PEPGetST(pep,&pep->st); }
1398:   STAppendOptionsPrefix(pep->st,prefix);
1399:   if (!pep->V) { PEPGetBV(pep,&pep->V); }
1400:   BVAppendOptionsPrefix(pep->V,prefix);
1401:   if (!pep->ds) { PEPGetDS(pep,&pep->ds); }
1402:   DSAppendOptionsPrefix(pep->ds,prefix);
1403:   if (!pep->rg) { PEPGetRG(pep,&pep->rg); }
1404:   RGAppendOptionsPrefix(pep->rg,prefix);
1405:   PetscObjectAppendOptionsPrefix((PetscObject)pep,prefix);
1406:   return(0);
1407: }

1409: /*@C
1410:    PEPGetOptionsPrefix - Gets the prefix used for searching for all
1411:    PEP options in the database.

1413:    Not Collective

1415:    Input Parameters:
1416: .  pep - the polynomial eigensolver context

1418:    Output Parameters:
1419: .  prefix - pointer to the prefix string used is returned

1421:    Note:
1422:    On the Fortran side, the user should pass in a string 'prefix' of
1423:    sufficient length to hold the prefix.

1425:    Level: advanced

1427: .seealso: PEPSetOptionsPrefix(), PEPAppendOptionsPrefix()
1428: @*/
1429: PetscErrorCode PEPGetOptionsPrefix(PEP pep,const char *prefix[])
1430: {

1436:   PetscObjectGetOptionsPrefix((PetscObject)pep,prefix);
1437:   return(0);
1438: }