Actual source code: basic.c

  1: /*
  2:      The basic EPS routines, Create, View, etc. are here.

  4:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  5:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  6:    Copyright (c) 2002-2011, Universitat Politecnica de Valencia, Spain

  8:    This file is part of SLEPc.
  9:       
 10:    SLEPc is free software: you can redistribute it and/or modify it under  the
 11:    terms of version 3 of the GNU Lesser General Public License as published by
 12:    the Free Software Foundation.

 14:    SLEPc  is  distributed in the hope that it will be useful, but WITHOUT  ANY 
 15:    WARRANTY;  without even the implied warranty of MERCHANTABILITY or  FITNESS 
 16:    FOR  A  PARTICULAR PURPOSE. See the GNU Lesser General Public  License  for 
 17:    more details.

 19:    You  should have received a copy of the GNU Lesser General  Public  License
 20:    along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
 21:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 22: */

 24: #include <private/epsimpl.h>      /*I "slepceps.h" I*/

 26: PetscFList       EPSList = 0;
 27: PetscBool        EPSRegisterAllCalled = PETSC_FALSE;
 28: PetscClassId     EPS_CLASSID = 0;
 29: PetscLogEvent    EPS_SetUp = 0,EPS_Solve = 0,EPS_Dense = 0;
 30: static PetscBool EPSPackageInitialized = PETSC_FALSE;

 32: const char *EPSPowerShiftTypes[] = {"CONSTANT","RAYLEIGH","WILKINSON","EPSPowerShiftType","EPS_POWER_SHIFT_",0};
 33: const char *EPSLanczosReorthogTypes[] = {"LOCAL","FULL","SELECTIVE","PERIODIC","PARTIAL","DELAYED","EPSLanczosReorthogType","EPS_LANCZOS_REORTHOG_",0};
 34: const char *EPSPRIMMEMethods[] = {"DYNAMIC","DEFAULT_MIN_TIME","DEFAULT_MIN_MATVECS","ARNOLDI","GD","GD_PLUSK","GD_OLSEN_PLUSK","JD_OLSEN_PLUSK","RQI","JDQR","JDQMR","JDQMR_ETOL","SUBSPACE_ITERATION","LOBPCG_ORTHOBASIS","LOBPCG_ORTHOBASISW","EPSPRIMMEMethod","EPS_PRIMME_",0};

 38: /*@C
 39:   EPSFinalizePackage - This function destroys everything in the Slepc interface to the EPS package. It is
 40:   called from SlepcFinalize().

 42:   Level: developer

 44: .seealso: SlepcFinalize()
 45: @*/
 46: PetscErrorCode EPSFinalizePackage(void)
 47: {
 49:   EPSPackageInitialized = PETSC_FALSE;
 50:   EPSList               = 0;
 51:   EPSRegisterAllCalled  = PETSC_FALSE;
 52:   return(0);
 53: }

 57: /*@C
 58:   EPSInitializePackage - This function initializes everything in the EPS package. It is called
 59:   from PetscDLLibraryRegister() when using dynamic libraries, and on the first call to EPSCreate()
 60:   when using static libraries.

 62:   Input Parameter:
 63:   path - The dynamic library path, or PETSC_NULL

 65:   Level: developer

 67: .seealso: SlepcInitialize()
 68: @*/
 69: PetscErrorCode EPSInitializePackage(const char *path) {
 70:   char           logList[256];
 71:   char           *className;
 72:   PetscBool      opt;

 76:   if (EPSPackageInitialized) return(0);
 77:   EPSPackageInitialized = PETSC_TRUE;
 78:   /* Register Classes */
 79:   PetscClassIdRegister("Eigenproblem Solver",&EPS_CLASSID);
 80:   /* Register Constructors */
 81:   EPSRegisterAll(path);
 82:   /* Register Events */
 83:   PetscLogEventRegister("EPSSetUp",EPS_CLASSID,&EPS_SetUp);
 84:   PetscLogEventRegister("EPSSolve",EPS_CLASSID,&EPS_Solve);
 85:   PetscLogEventRegister("EPSDense",EPS_CLASSID,&EPS_Dense);
 86:   /* Process info exclusions */
 87:   PetscOptionsGetString(PETSC_NULL,"-info_exclude",logList,256,&opt);
 88:   if (opt) {
 89:     PetscStrstr(logList,"eps",&className);
 90:     if (className) {
 91:       PetscInfoDeactivateClass(EPS_CLASSID);
 92:     }
 93:   }
 94:   /* Process summary exclusions */
 95:   PetscOptionsGetString(PETSC_NULL,"-log_summary_exclude",logList,256,&opt);
 96:   if (opt) {
 97:     PetscStrstr(logList,"eps",&className);
 98:     if (className) {
 99:       PetscLogEventDeactivateClass(EPS_CLASSID);
100:     }
101:   }
102:   PetscRegisterFinalize(EPSFinalizePackage);
103:   return(0);
104: }

108: /*@C
109:    EPSView - Prints the EPS data structure.

111:    Collective on EPS

113:    Input Parameters:
114: +  eps - the eigenproblem solver context
115: -  viewer - optional visualization context

117:    Options Database Key:
118: .  -eps_view -  Calls EPSView() at end of EPSSolve()

120:    Note:
121:    The available visualization contexts include
122: +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
123: -     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
124:          output where only the first processor opens
125:          the file.  All other processors send their 
126:          data to the first processor to print. 

128:    The user can open an alternative visualization context with
129:    PetscViewerASCIIOpen() - output to a specified file.

131:    Level: beginner

133: .seealso: STView(), PetscViewerASCIIOpen()
134: @*/
135: PetscErrorCode EPSView(EPS eps,PetscViewer viewer)
136: {
138:   const char     *type,*extr,*bal;
139:   PetscBool      isascii;

143:   if (!viewer) viewer = PETSC_VIEWER_STDOUT_(((PetscObject)eps)->comm);

147: #if defined(PETSC_USE_COMPLEX)
148: #define HERM "hermitian"
149: #else
150: #define HERM "symmetric"
151: #endif
152:   PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii);
153:   if (isascii) {
154:     PetscObjectPrintClassNamePrefixType((PetscObject)eps,viewer,"EPS Object");
155:     if (eps->ops->view) {
156:       PetscViewerASCIIPushTab(viewer);
157:       (*eps->ops->view)(eps,viewer);
158:       PetscViewerASCIIPopTab(viewer);
159:     }
160:     if (eps->problem_type) {
161:       switch (eps->problem_type) {
162:         case EPS_HEP:   type = HERM " eigenvalue problem"; break;
163:         case EPS_GHEP:  type = "generalized " HERM " eigenvalue problem"; break;
164:         case EPS_NHEP:  type = "non-" HERM " eigenvalue problem"; break;
165:         case EPS_GNHEP: type = "generalized non-" HERM " eigenvalue problem"; break;
166:         case EPS_PGNHEP: type = "generalized non-" HERM " eigenvalue problem with " HERM " positive definite B"; break;
167:         default: SETERRQ(((PetscObject)eps)->comm,1,"Wrong value of eps->problem_type");
168:       }
169:     } else type = "not yet set";
170:     PetscViewerASCIIPrintf(viewer,"  problem type: %s\n",type);
171:     if (eps->extraction) {
172:       switch (eps->extraction) {
173:         case EPS_RITZ:             extr = "Rayleigh-Ritz"; break;
174:         case EPS_HARMONIC:         extr = "harmonic Ritz"; break;
175:         case EPS_HARMONIC_RELATIVE:extr = "relative harmonic Ritz"; break;
176:         case EPS_HARMONIC_RIGHT:   extr = "right harmonic Ritz"; break;
177:         case EPS_HARMONIC_LARGEST: extr = "largest harmonic Ritz"; break;
178:         case EPS_REFINED:          extr = "refined Ritz"; break;
179:         case EPS_REFINED_HARMONIC: extr = "refined harmonic Ritz"; break;
180:         default: SETERRQ(((PetscObject)eps)->comm,1,"Wrong value of eps->extraction");
181:       }
182:       PetscViewerASCIIPrintf(viewer,"  extraction type: %s\n",extr);
183:     }
184:     if (eps->balance && !eps->ishermitian && eps->balance!=EPS_BALANCE_NONE) {
185:       switch (eps->balance) {
186:         case EPS_BALANCE_ONESIDE:   bal = "one-sided Krylov"; break;
187:         case EPS_BALANCE_TWOSIDE:   bal = "two-sided Krylov"; break;
188:         case EPS_BALANCE_USER:      bal = "user-defined matrix"; break;
189:         default: SETERRQ(((PetscObject)eps)->comm,1,"Wrong value of eps->balance");
190:       }
191:       PetscViewerASCIIPrintf(viewer,"  balancing enabled: %s",bal);
192:       if (eps->balance==EPS_BALANCE_ONESIDE || eps->balance==EPS_BALANCE_TWOSIDE) {
193:         PetscViewerASCIIPrintf(viewer,", with its=%D",eps->balance_its);
194:       }
195:       if (eps->balance==EPS_BALANCE_TWOSIDE && eps->balance_cutoff!=0.0) {
196:         PetscViewerASCIIPrintf(viewer," and cutoff=%G",eps->balance_cutoff);
197:       }
198:       PetscViewerASCIIPrintf(viewer,"\n");
199:     }
200:     PetscViewerASCIIPrintf(viewer,"  selected portion of the spectrum: ");
201:     if (!eps->which) {
202:       PetscViewerASCIIPrintf(viewer,"not yet set\n");
203:     } else switch (eps->which) {
204:       case EPS_WHICH_USER:
205:         PetscViewerASCIIPrintf(viewer,"user defined\n");
206:         break;
207:       case EPS_TARGET_MAGNITUDE:
208: #if !defined(PETSC_USE_COMPLEX)
209:         PetscViewerASCIIPrintf(viewer,"closest to target: %G (in magnitude)\n",eps->target);
210: #else
211:         PetscViewerASCIIPrintf(viewer,"closest to target: %G+%G i (in magnitude)\n",PetscRealPart(eps->target),PetscImaginaryPart(eps->target));
212: #endif
213:         break;
214:       case EPS_TARGET_REAL:
215: #if !defined(PETSC_USE_COMPLEX)
216:         PetscViewerASCIIPrintf(viewer,"closest to target: %G (along the real axis)\n",eps->target);
217: #else
218:         PetscViewerASCIIPrintf(viewer,"closest to target: %G+%G i (along the real axis)\n",PetscRealPart(eps->target),PetscImaginaryPart(eps->target));
219: #endif
220:         break;
221: #if defined(PETSC_USE_COMPLEX)
222:       case EPS_TARGET_IMAGINARY:
223:         PetscViewerASCIIPrintf(viewer,"closest to target: %G+%G i (along the imaginary axis)\n",PetscRealPart(eps->target),PetscImaginaryPart(eps->target));
224:         break;
225: #endif
226:       case EPS_LARGEST_MAGNITUDE:
227:         PetscViewerASCIIPrintf(viewer,"largest eigenvalues in magnitude\n");
228:         break;
229:       case EPS_SMALLEST_MAGNITUDE:
230:         PetscViewerASCIIPrintf(viewer,"smallest eigenvalues in magnitude\n");
231:         break;
232:       case EPS_LARGEST_REAL:
233:         PetscViewerASCIIPrintf(viewer,"largest real parts\n");
234:         break;
235:       case EPS_SMALLEST_REAL:
236:         PetscViewerASCIIPrintf(viewer,"smallest real parts\n");
237:         break;
238:       case EPS_LARGEST_IMAGINARY:
239:         PetscViewerASCIIPrintf(viewer,"largest imaginary parts\n");
240:         break;
241:       case EPS_SMALLEST_IMAGINARY:
242:         PetscViewerASCIIPrintf(viewer,"smallest imaginary parts\n");
243:         break;
244:       case EPS_ALL:
245:         PetscViewerASCIIPrintf(viewer,"all eigenvalues in interval [%G,%G]\n",eps->inta,eps->intb);
246:         break;
247:       default: SETERRQ(((PetscObject)eps)->comm,1,"Wrong value of eps->which");
248:     }
249:     if (eps->leftvecs) {
250:       PetscViewerASCIIPrintf(viewer,"  computing left eigenvectors also\n");
251:     }
252:     if (eps->trueres) {
253:       PetscViewerASCIIPrintf(viewer,"  computing true residuals explicitly\n");
254:     }
255:     if (eps->trackall) {
256:       PetscViewerASCIIPrintf(viewer,"  computing all residuals (for tracking convergence)\n");
257:     }
258:     PetscViewerASCIIPrintf(viewer,"  number of eigenvalues (nev): %D\n",eps->nev);
259:     PetscViewerASCIIPrintf(viewer,"  number of column vectors (ncv): %D\n",eps->ncv);
260:     PetscViewerASCIIPrintf(viewer,"  maximum dimension of projected problem (mpd): %D\n",eps->mpd);
261:     PetscViewerASCIIPrintf(viewer,"  maximum number of iterations: %D\n",eps->max_it);
262:     PetscViewerASCIIPrintf(viewer,"  tolerance: %G\n",eps->tol);
263:     PetscViewerASCIIPrintf(viewer,"  convergence test: ");
264:     switch(eps->conv) {
265:     case EPS_CONV_ABS:
266:       PetscViewerASCIIPrintf(viewer,"absolute\n");break;
267:     case EPS_CONV_EIG:
268:       PetscViewerASCIIPrintf(viewer,"relative to the eigenvalue\n");break;
269:     case EPS_CONV_NORM:
270:       PetscViewerASCIIPrintf(viewer,"relative to the eigenvalue and matrix norms\n");break;
271:     default:
272:       PetscViewerASCIIPrintf(viewer,"user-defined\n");break;
273:     }
274:     if (eps->nini!=0) {
275:       PetscViewerASCIIPrintf(viewer,"  dimension of user-provided initial space: %D\n",PetscAbs(eps->nini));
276:     }
277:     if (eps->ninil!=0) {
278:       PetscViewerASCIIPrintf(viewer,"  dimension of user-provided initial left space: %D\n",PetscAbs(eps->ninil));
279:     }
280:     if (eps->nds>0) {
281:       PetscViewerASCIIPrintf(viewer,"  dimension of user-provided deflation space: %D\n",eps->nds);
282:     }
283:     PetscViewerASCIIPrintf(viewer,"  estimates of matrix norms (%s): norm(A)=%G",eps->adaptive?"adaptive":"constant",eps->nrma);
284:     if (eps->isgeneralized) {
285:       PetscViewerASCIIPrintf(viewer,", norm(B)=%G",eps->nrmb);
286:     }
287:     PetscViewerASCIIPrintf(viewer,"\n");
288:   } else {
289:     if (eps->ops->view) {
290:       (*eps->ops->view)(eps,viewer);
291:     }
292:   }
293:   if (!eps->ip) { EPSGetIP(eps,&eps->ip); }
294:   IPView(eps->ip,viewer);
295:   if (!eps->OP) { EPSGetST(eps,&eps->OP); }
296:   STView(eps->OP,viewer);
297:   return(0);
298: }

302: /*@
303:    EPSPrintSolution - Prints the computed eigenvalues.

305:    Collective on EPS

307:    Input Parameters:
308: +  eps - the eigensolver context
309: -  viewer - optional visualization context

311:    Options Database:
312: .  -eps_terse - print only minimal information

314:    Note:
315:    By default, this function prints a table with eigenvalues and associated
316:    relative errors. With -eps_terse only the eigenvalues are printed.

318:    Level: intermediate

320: .seealso: PetscViewerASCIIOpen()
321: @*/
322: PetscErrorCode EPSPrintSolution(EPS eps,PetscViewer viewer)
323: {
324:   PetscBool      terse,errok,isascii;
325:   PetscReal      error,re,im;
326:   PetscScalar    kr,ki;
327:   PetscInt       i,j;

332:   if (!viewer) viewer = PETSC_VIEWER_STDOUT_(((PetscObject)eps)->comm);
335:   if (!eps->eigr || !eps->eigi || !eps->V) {
336:     SETERRQ(((PetscObject)eps)->comm,PETSC_ERR_ARG_WRONGSTATE,"EPSSolve must be called first");
337:   }
338:   PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii);
339:   if (!isascii) return(0);

341:   PetscOptionsHasName(PETSC_NULL,"-eps_terse",&terse);
342:   if (terse) {
343:     if (eps->nconv<eps->nev) {
344:       PetscViewerASCIIPrintf(viewer," Problem: less than %D eigenvalues converged\n\n",eps->nev);
345:     } else {
346:       errok = PETSC_TRUE;
347:       for (i=0;i<eps->nev;i++) {
348:         EPSComputeRelativeError(eps,i,&error);
349:         errok = (errok && error<eps->tol)? PETSC_TRUE: PETSC_FALSE;
350:       }
351:       if (errok) {
352:         PetscViewerASCIIPrintf(viewer," All requested eigenvalues computed up to the required tolerance:");
353:         for (i=0;i<=(eps->nev-1)/8;i++) {
354:           PetscViewerASCIIPrintf(viewer,"\n     ");
355:           for (j=0;j<PetscMin(8,eps->nev-8*i);j++) {
356:             EPSGetEigenpair(eps,8*i+j,&kr,&ki,PETSC_NULL,PETSC_NULL);
357: #if defined(PETSC_USE_COMPLEX)
358:             re = PetscRealPart(kr);
359:             im = PetscImaginaryPart(kr);
360: #else
361:             re = kr;
362:             im = ki;
363: #endif 
364:             if (PetscAbs(re)/PetscAbs(im)<PETSC_SMALL) re = 0.0;
365:             if (PetscAbs(im)/PetscAbs(re)<PETSC_SMALL) im = 0.0;
366:             if (im!=0.0) {
367:               PetscViewerASCIIPrintf(viewer,"%.5F%+.5Fi",re,im);
368:             } else {
369:               PetscViewerASCIIPrintf(viewer,"%.5F",re);
370:             }
371:             if (8*i+j+1<eps->nev) { PetscViewerASCIIPrintf(viewer,", "); }
372:           }
373:         }
374:         PetscViewerASCIIPrintf(viewer,"\n\n");
375:       } else {
376:         PetscViewerASCIIPrintf(viewer," Problem: some of the first %D relative errors are higher than the tolerance\n\n",eps->nev);
377:       }
378:     }
379:   } else {
380:     PetscViewerASCIIPrintf(viewer," Number of converged approximate eigenpairs: %D\n\n",eps->nconv);
381:     if (eps->nconv>0) {
382:       PetscViewerASCIIPrintf(viewer,
383:            "           k          ||Ax-k%sx||/||kx||\n"
384:            "   ----------------- ------------------\n",eps->isgeneralized?"B":"");
385:       for (i=0;i<eps->nconv;i++) {
386:         EPSGetEigenpair(eps,i,&kr,&ki,PETSC_NULL,PETSC_NULL);
387:         EPSComputeRelativeError(eps,i,&error);
388: #if defined(PETSC_USE_COMPLEX)
389:         re = PetscRealPart(kr);
390:         im = PetscImaginaryPart(kr);
391: #else
392:         re = kr;
393:         im = ki;
394: #endif 
395:         if (im!=0.0) {
396:           PetscViewerASCIIPrintf(viewer," % 9F%+9F i %12G\n",re,im,error);
397:         } else {
398:           PetscViewerASCIIPrintf(viewer,"   % 12F       %12G\n",re,error);
399:         }
400:       }
401:       PetscViewerASCIIPrintf(viewer,"\n");
402:     }
403:   }
404:   return(0);
405: }

409: /*@C
410:    EPSCreate - Creates the default EPS context.

412:    Collective on MPI_Comm

414:    Input Parameter:
415: .  comm - MPI communicator

417:    Output Parameter:
418: .  eps - location to put the EPS context

420:    Note:
421:    The default EPS type is EPSKRYLOVSCHUR

423:    Level: beginner

425: .seealso: EPSSetUp(), EPSSolve(), EPSDestroy(), EPS
426: @*/
427: PetscErrorCode EPSCreate(MPI_Comm comm,EPS *outeps)
428: {
430:   EPS            eps;

434:   *outeps = 0;

436:   PetscHeaderCreate(eps,_p_EPS,struct _EPSOps,EPS_CLASSID,-1,"EPS","Eigenvalue Problem Solver","EPS",comm,EPSDestroy,EPSView);

438:   eps->max_it          = 0;
439:   eps->nev             = 1;
440:   eps->ncv             = 0;
441:   eps->mpd             = 0;
442:   eps->allocated_ncv   = 0;
443:   eps->nini            = 0;
444:   eps->ninil           = 0;
445:   eps->nds             = 0;
446:   eps->tol             = PETSC_DEFAULT;
447:   eps->conv            = EPS_CONV_EIG;
448:   eps->conv_func       = EPSEigRelativeConverged;
449:   eps->conv_ctx        = PETSC_NULL;
450:   eps->which           = (EPSWhich)0;
451:   eps->which_func      = PETSC_NULL;
452:   eps->which_ctx       = PETSC_NULL;
453:   eps->leftvecs        = PETSC_FALSE;
454:   eps->trueres         = PETSC_FALSE;
455:   eps->trackall        = PETSC_FALSE;
456:   eps->target          = 0.0;
457:   eps->inta            = 0.0;
458:   eps->intb            = 0.0;
459:   eps->evecsavailable  = PETSC_FALSE;
460:   eps->problem_type    = (EPSProblemType)0;
461:   eps->extraction      = (EPSExtraction)0;
462:   eps->balance         = (EPSBalance)0;
463:   eps->balance_its     = 5;
464:   eps->balance_cutoff  = 1e-8;
465:   eps->nrma            = 1.0;
466:   eps->nrmb            = 1.0;
467:   eps->adaptive        = PETSC_FALSE;

469:   eps->V               = 0;
470:   eps->W               = 0;
471:   eps->T               = 0;
472:   eps->D               = 0;
473:   eps->DS              = 0;
474:   eps->IS              = 0;
475:   eps->ISL             = 0;
476:   eps->t               = 0;
477:   eps->ds_ortho        = PETSC_FALSE;
478:   eps->eigr            = 0;
479:   eps->eigi            = 0;
480:   eps->errest          = 0;
481:   eps->errest_left     = 0;
482:   eps->OP              = 0;
483:   eps->ip              = 0;
484:   eps->rand            = 0;
485:   eps->data            = 0;
486:   eps->nconv           = 0;
487:   eps->its             = 0;
488:   eps->perm            = PETSC_NULL;

490:   eps->nwork           = 0;
491:   eps->work            = 0;
492:   eps->isgeneralized   = PETSC_FALSE;
493:   eps->ishermitian     = PETSC_FALSE;
494:   eps->ispositive      = PETSC_FALSE;
495:   eps->setupcalled     = 0;
496:   eps->reason          = EPS_CONVERGED_ITERATING;
497:   eps->numbermonitors  = 0;

499:   PetscRandomCreate(comm,&eps->rand);
500:   PetscLogObjectParent(eps,eps->rand);
501:   *outeps = eps;
502:   return(0);
503: }
504: 
507: /*@C
508:    EPSSetType - Selects the particular solver to be used in the EPS object. 

510:    Logically Collective on EPS

512:    Input Parameters:
513: +  eps  - the eigensolver context
514: -  type - a known method

516:    Options Database Key:
517: .  -eps_type <method> - Sets the method; use -help for a list 
518:     of available methods 
519:     
520:    Notes:  
521:    See "slepc/include/slepceps.h" for available methods. The default
522:    is EPSKRYLOVSCHUR.

524:    Normally, it is best to use the EPSSetFromOptions() command and
525:    then set the EPS type from the options database rather than by using
526:    this routine.  Using the options database provides the user with
527:    maximum flexibility in evaluating the different available methods.
528:    The EPSSetType() routine is provided for those situations where it
529:    is necessary to set the iterative solver independently of the command
530:    line or options database. 

532:    Level: intermediate

534: .seealso: STSetType(), EPSType
535: @*/
536: PetscErrorCode EPSSetType(EPS eps,const EPSType type)
537: {
538:   PetscErrorCode ierr,(*r)(EPS);
539:   PetscBool      match;


545:   PetscTypeCompare((PetscObject)eps,type,&match);
546:   if (match) return(0);

548:   PetscFListFind(EPSList,((PetscObject)eps)->comm,type,PETSC_TRUE,(void (**)(void)) &r);
549:   if (!r) SETERRQ1(((PetscObject)eps)->comm,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unknown EPS type given: %s",type);

551:   if (eps->ops->destroy) { (*eps->ops->destroy)(eps); }
552:   PetscMemzero(eps->ops,sizeof(struct _EPSOps));

554:   eps->setupcalled = 0;
555:   PetscObjectChangeTypeName((PetscObject)eps,type);
556:   (*r)(eps);
557:   return(0);
558: }

562: /*@C
563:    EPSGetType - Gets the EPS type as a string from the EPS object.

565:    Not Collective

567:    Input Parameter:
568: .  eps - the eigensolver context 

570:    Output Parameter:
571: .  name - name of EPS method 

573:    Level: intermediate

575: .seealso: EPSSetType()
576: @*/
577: PetscErrorCode EPSGetType(EPS eps,const EPSType *type)
578: {
582:   *type = ((PetscObject)eps)->type_name;
583:   return(0);
584: }

588: /*@C
589:   EPSRegister - See EPSRegisterDynamic()

591:   Level: advanced
592: @*/
593: PetscErrorCode EPSRegister(const char *sname,const char *path,const char *name,PetscErrorCode (*function)(EPS))
594: {
596:   char           fullname[PETSC_MAX_PATH_LEN];

599:   PetscFListConcat(path,name,fullname);
600:   PetscFListAdd(&EPSList,sname,fullname,(void (*)(void))function);
601:   return(0);
602: }

606: /*@
607:    EPSRegisterDestroy - Frees the list of EPS methods that were
608:    registered by EPSRegisterDynamic().

610:    Not Collective

612:    Level: advanced

614: .seealso: EPSRegisterDynamic(), EPSRegisterAll()
615: @*/
616: PetscErrorCode EPSRegisterDestroy(void)
617: {

621:   PetscFListDestroy(&EPSList);
622:   EPSRegisterAllCalled = PETSC_FALSE;
623:   return(0);
624: }

628: /*@
629:    EPSReset - Resets the EPS context to the setupcalled=0 state and removes any
630:    allocated objects.

632:    Collective on EPS

634:    Input Parameter:
635: .  eps - eigensolver context obtained from EPSCreate()

637:    Level: advanced

639: .seealso: EPSDestroy()
640: @*/
641: PetscErrorCode EPSReset(EPS eps)
642: {

647:   if (eps->ops->reset) { (eps->ops->reset)(eps); }
648:   if (eps->OP) { STReset(eps->OP); }
649:   if (eps->ip) { IPReset(eps->ip); }
650:   VecDestroy(&eps->t);
651:   VecDestroy(&eps->D);
652:   eps->setupcalled = 0;
653:   return(0);
654: }

658: /*@C
659:    EPSDestroy - Destroys the EPS context.

661:    Collective on EPS

663:    Input Parameter:
664: .  eps - eigensolver context obtained from EPSCreate()

666:    Level: beginner

668: .seealso: EPSCreate(), EPSSetUp(), EPSSolve()
669: @*/
670: PetscErrorCode EPSDestroy(EPS *eps)
671: {

675:   if (!*eps) return(0);
677:   if (--((PetscObject)(*eps))->refct > 0) { *eps = 0; return(0); }
678:   EPSReset(*eps);
679:   PetscObjectDepublish(*eps);
680:   if ((*eps)->ops->destroy) { (*(*eps)->ops->destroy)(*eps); }
681:   STDestroy(&(*eps)->OP);
682:   IPDestroy(&(*eps)->ip);
683:   PetscRandomDestroy(&(*eps)->rand);
684:   EPSRemoveDeflationSpace(*eps);
685:   EPSMonitorCancel(*eps);
686:   PetscHeaderDestroy(eps);
687:   return(0);
688: }

692: /*@
693:    EPSSetTarget - Sets the value of the target.

695:    Logically Collective on EPS

697:    Input Parameters:
698: +  eps    - eigensolver context
699: -  target - the value of the target

701:    Notes:
702:    The target is a scalar value used to determine the portion of the spectrum
703:    of interest. It is used in combination with EPSSetWhichEigenpairs().
704:    
705:    Level: beginner

707: .seealso: EPSGetTarget(), EPSSetWhichEigenpairs()
708: @*/
709: PetscErrorCode EPSSetTarget(EPS eps,PetscScalar target)
710: {

716:   eps->target = target;
717:   if (!eps->OP) { EPSGetST(eps,&eps->OP); }
718:   STSetDefaultShift(eps->OP,target);
719:   return(0);
720: }

724: /*@
725:    EPSGetTarget - Gets the value of the target.

727:    Not Collective

729:    Input Parameter:
730: .  eps - eigensolver context

732:    Output Parameter:
733: .  target - the value of the target

735:    Level: beginner

737:    Note:
738:    If the target was not set by the user, then zero is returned.

740: .seealso: EPSSetTarget()
741: @*/
742: PetscErrorCode EPSGetTarget(EPS eps,PetscScalar* target)
743: {
747:   *target = eps->target;
748:   return(0);
749: }

753: /*@
754:    EPSSetInterval - Defines the computational interval for spectrum slicing.

756:    Logically Collective on EPS

758:    Input Parameters:
759: +  eps  - eigensolver context
760: .  inta - left end of the interval
761: -  intb - right end of the interval

763:    Options Database Key:
764: .  -eps_interval <a,b> - set [a,b] as the interval of interest

766:    Notes:
767:    Spectrum slicing is a technique employed for computing all eigenvalues of
768:    symmetric eigenproblems in a given interval. This function provides the
769:    interval to be considered. It must be used in combination with EPS_ALL, see
770:    EPSSetWhichEigenpairs().

772:    In the command-line option, two values must be provided. For an open interval,
773:    one can give an infinite, e.g., -eps_interval 1.0,inf or -eps_interval -inf,1.0.
774:    An open interval in the programmatic intervace can be specified with 
775:    PETSC_MAX_REAL and -PETSC_MAX_REAL.
776:    
777:    Level: intermediate

779: .seealso: EPSGetInterval(), EPSSetWhichEigenpairs()
780: @*/
781: PetscErrorCode EPSSetInterval(EPS eps,PetscReal inta,PetscReal intb)
782: {
787:   if (inta>=intb) SETERRQ(((PetscObject)eps)->comm,PETSC_ERR_ARG_WRONG,"Badly defined interval, must be inta<intb");
788:   eps->inta = inta;
789:   eps->intb = intb;
790:   return(0);
791: }

795: /*@
796:    EPSGetInterval - Gets the computational interval for spectrum slicing.

798:    Not Collective

800:    Input Parameter:
801: .  eps - eigensolver context

803:    Output Parameters:
804: +  inta - left end of the interval
805: -  intb - right end of the interval

807:    Level: intermediate

809:    Note:
810:    If the interval was not set by the user, then zeros are returned.

812: .seealso: EPSSetInterval()
813: @*/
814: PetscErrorCode EPSGetInterval(EPS eps,PetscReal* inta,PetscReal* intb)
815: {
820:   if (inta) *inta = eps->inta;
821:   if (intb) *intb = eps->intb;
822:   return(0);
823: }

827: /*@
828:    EPSSetST - Associates a spectral transformation object to the eigensolver. 

830:    Collective on EPS

832:    Input Parameters:
833: +  eps - eigensolver context obtained from EPSCreate()
834: -  st   - the spectral transformation object

836:    Note:
837:    Use EPSGetST() to retrieve the spectral transformation context (for example,
838:    to free it at the end of the computations).

840:    Level: developer

842: .seealso: EPSGetST()
843: @*/
844: PetscErrorCode EPSSetST(EPS eps,ST st)
845: {

852:   PetscObjectReference((PetscObject)st);
853:   STDestroy(&eps->OP);
854:   eps->OP = st;
855:   PetscLogObjectParent(eps,eps->OP);
856:   return(0);
857: }

861: /*@C
862:    EPSGetST - Obtain the spectral transformation (ST) object associated
863:    to the eigensolver object.

865:    Not Collective

867:    Input Parameters:
868: .  eps - eigensolver context obtained from EPSCreate()

870:    Output Parameter:
871: .  st - spectral transformation context

873:    Level: beginner

875: .seealso: EPSSetST()
876: @*/
877: PetscErrorCode EPSGetST(EPS eps,ST *st)
878: {

884:   if (!eps->OP) {
885:     STCreate(((PetscObject)eps)->comm,&eps->OP);
886:     PetscLogObjectParent(eps,eps->OP);
887:   }
888:   *st = eps->OP;
889:   return(0);
890: }

894: /*@
895:    EPSSetIP - Associates an inner product object to the eigensolver. 

897:    Collective on EPS

899:    Input Parameters:
900: +  eps - eigensolver context obtained from EPSCreate()
901: -  ip  - the inner product object

903:    Note:
904:    Use EPSGetIP() to retrieve the inner product context (for example,
905:    to free it at the end of the computations).

907:    Level: advanced

909: .seealso: EPSGetIP()
910: @*/
911: PetscErrorCode EPSSetIP(EPS eps,IP ip)
912: {

919:   PetscObjectReference((PetscObject)ip);
920:   IPDestroy(&eps->ip);
921:   eps->ip = ip;
922:   PetscLogObjectParent(eps,eps->ip);
923:   return(0);
924: }

928: /*@C
929:    EPSGetIP - Obtain the inner product object associated to the eigensolver object.

931:    Not Collective

933:    Input Parameters:
934: .  eps - eigensolver context obtained from EPSCreate()

936:    Output Parameter:
937: .  ip - inner product context

939:    Level: advanced

941: .seealso: EPSSetIP()
942: @*/
943: PetscErrorCode EPSGetIP(EPS eps,IP *ip)
944: {

950:   if (!eps->ip) {
951:     IPCreate(((PetscObject)eps)->comm,&eps->ip);
952:     PetscLogObjectParent(eps,eps->ip);
953:   }
954:   *ip = eps->ip;
955:   return(0);
956: }

960: /*@
961:    EPSIsGeneralized - Ask if the EPS object corresponds to a generalized 
962:    eigenvalue problem.

964:    Not collective

966:    Input Parameter:
967: .  eps - the eigenproblem solver context

969:    Output Parameter:
970: .  is - the answer

972:    Level: intermediate

974: .seealso: EPSIsHermitian()
975: @*/
976: PetscErrorCode EPSIsGeneralized(EPS eps,PetscBool* is)
977: {
980:   *is = eps->isgeneralized;
981:   return(0);
982: }

986: /*@
987:    EPSIsHermitian - Ask if the EPS object corresponds to a Hermitian 
988:    eigenvalue problem.

990:    Not collective

992:    Input Parameter:
993: .  eps - the eigenproblem solver context

995:    Output Parameter:
996: .  is - the answer

998:    Level: intermediate

1000: .seealso: EPSIsGeneralized()
1001: @*/
1002: PetscErrorCode EPSIsHermitian(EPS eps,PetscBool* is)
1003: {
1006:   *is = eps->ishermitian;
1007:   return(0);
1008: }