Actual source code: nleigs-fullb.c

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

  6:    This file is part of SLEPc.
  7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
  8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  9: */
 10: /*
 11:    Full basis for the linearization of the rational approximation of non-linear eigenproblems
 12: */

 14: #include <slepc/private/nepimpl.h>
 15: #include "nleigs.h"

 17: static PetscErrorCode MatMult_FullBasis_Sinvert(Mat M,Vec x,Vec y)
 18: {
 19:   NEP_NLEIGS        *ctx;
 20:   NEP               nep;
 21:   const PetscScalar *px;
 22:   PetscScalar       *beta,*s,*xi,*t,*py,sigma;
 23:   PetscInt          nmat,d,i,k,m;
 24:   Vec               xx,xxx,yy,yyy,w,ww,www;

 26:   MatShellGetContext(M,&nep);
 27:   ctx = (NEP_NLEIGS*)nep->data;
 28:   beta = ctx->beta; s = ctx->s; xi = ctx->xi;
 29:   sigma = ctx->shifts[0];
 30:   nmat = ctx->nmat;
 31:   d = nmat-1;
 32:   m = nep->nloc;
 33:   PetscMalloc1(ctx->nmat,&t);
 34:   xx = ctx->w[0]; xxx = ctx->w[1]; yy = ctx->w[2]; yyy=ctx->w[3];
 35:   w = nep->work[0]; ww = nep->work[1]; www = nep->work[2];
 36:   VecGetArrayRead(x,&px);
 37:   VecGetArray(y,&py);
 38:   VecPlaceArray(xx,px+(d-1)*m);
 39:   VecPlaceArray(xxx,px+(d-2)*m);
 40:   VecPlaceArray(yy,py+(d-2)*m);
 41:   VecCopy(xxx,yy);
 42:   VecAXPY(yy,beta[d-1]/xi[d-2],xx);
 43:   VecScale(yy,1.0/(s[d-2]-sigma));
 44:   VecResetArray(xx);
 45:   VecResetArray(xxx);
 46:   VecResetArray(yy);
 47:   for (i=d-3;i>=0;i--) {
 48:     VecPlaceArray(xx,px+(i+1)*m);
 49:     VecPlaceArray(xxx,px+i*m);
 50:     VecPlaceArray(yy,py+i*m);
 51:     VecPlaceArray(yyy,py+(i+1)*m);
 52:     VecCopy(xxx,yy);
 53:     VecAXPY(yy,beta[i+1]/xi[i],xx);
 54:     VecAXPY(yy,-beta[i+1]*(1.0-sigma/xi[i]),yyy);
 55:     VecScale(yy,1.0/(s[i]-sigma));
 56:     VecResetArray(xx);
 57:     VecResetArray(xxx);
 58:     VecResetArray(yy);
 59:     VecResetArray(yyy);
 60:   }
 61:   if (nep->fui==NEP_USER_INTERFACE_SPLIT) {
 62:     VecZeroEntries(w);
 63:     for (k=0;k<nep->nt;k++) {
 64:       VecZeroEntries(ww);
 65:       VecPlaceArray(xx,px+(d-1)*m);
 66:       VecAXPY(ww,-ctx->coeffD[k+nep->nt*d]/beta[d],xx);
 67:       VecResetArray(xx);
 68:       for (i=0;i<d-1;i++) {
 69:         VecPlaceArray(yy,py+i*m);
 70:         VecAXPY(ww,-ctx->coeffD[nep->nt*i+k],yy);
 71:         VecResetArray(yy);
 72:       }
 73:       MatMult(nep->A[k],ww,www);
 74:       VecAXPY(w,1.0,www);
 75:     }
 76:   } else {
 77:     VecPlaceArray(xx,px+(d-1)*m);
 78:     MatMult(ctx->D[d],xx,w);
 79:     VecScale(w,-1.0/beta[d]);
 80:     VecResetArray(xx);
 81:     for (i=0;i<d-1;i++) {
 82:       VecPlaceArray(yy,py+i*m);
 83:       MatMult(ctx->D[i],yy,ww);
 84:       VecResetArray(yy);
 85:       VecAXPY(w,-1.0,ww);
 86:     }
 87:   }
 88:   VecPlaceArray(yy,py+(d-1)*m);
 89:   KSPSolve(ctx->ksp[0],w,yy);
 90:   NEPNLEIGSEvalNRTFunct(nep,d-1,sigma,t);
 91:   for (i=0;i<d-1;i++) {
 92:     VecPlaceArray(yyy,py+i*m);
 93:     VecAXPY(yyy,t[i],yy);
 94:     VecResetArray(yyy);
 95:   }
 96:   VecScale(yy,t[d-1]);
 97:   VecResetArray(yy);
 98:   VecRestoreArrayRead(x,&px);
 99:   VecRestoreArray(y,&py);
100:   PetscFree(t);
101:   return 0;
102: }

104: static PetscErrorCode MatMultTranspose_FullBasis_Sinvert(Mat M,Vec x,Vec y)
105: {
106:   NEP_NLEIGS        *ctx;
107:   NEP               nep;
108:   const PetscScalar *px;
109:   PetscScalar       *beta,*s,*xi,*t,*py,sigma;
110:   PetscInt          nmat,d,i,k,m;
111:   Vec               xx,yy,yyy,w,z0;

113:   MatShellGetContext(M,&nep);
114:   ctx = (NEP_NLEIGS*)nep->data;
115:   beta = ctx->beta; s = ctx->s; xi = ctx->xi;
116:   sigma = ctx->shifts[0];
117:   nmat = ctx->nmat;
118:   d = nmat-1;
119:   m = nep->nloc;
120:   PetscMalloc1(ctx->nmat,&t);
121:   xx = ctx->w[0]; yy = ctx->w[1]; yyy=ctx->w[2];
122:   w = nep->work[0]; z0 = nep->work[1];
123:   VecGetArrayRead(x,&px);
124:   VecGetArray(y,&py);
125:   NEPNLEIGSEvalNRTFunct(nep,d,sigma,t);
126:   VecPlaceArray(xx,px+(d-1)*m);
127:   VecCopy(xx,w);
128:   VecScale(w,t[d-1]);
129:   VecResetArray(xx);
130:   for (i=0;i<d-1;i++) {
131:     VecPlaceArray(xx,px+i*m);
132:     VecAXPY(w,t[i],xx);
133:     VecResetArray(xx);
134:   }
135:   KSPSolveTranspose(ctx->ksp[0],w,z0);

137:   VecPlaceArray(yy,py);
138:   if (nep->fui==NEP_USER_INTERFACE_SPLIT) {
139:     VecZeroEntries(yy);
140:     for (k=0;k<nep->nt;k++) {
141:       MatMult(nep->A[k],z0,w);
142:       VecAXPY(yy,ctx->coeffD[k],w);
143:     }
144:   } else MatMultTranspose(ctx->D[0],z0,yy);
145:   VecPlaceArray(xx,px);
146:   VecAXPY(yy,-1.0,xx);
147:   VecResetArray(xx);
148:   VecScale(yy,-1.0/(s[0]-sigma));
149:   VecResetArray(yy);
150:   for (i=2;i<d;i++) {
151:     VecPlaceArray(yy,py+(i-1)*m);
152:     if (nep->fui==NEP_USER_INTERFACE_SPLIT) {
153:       VecZeroEntries(yy);
154:       for (k=0;k<nep->nt;k++) {
155:         MatMult(nep->A[k],z0,w);
156:         VecAXPY(yy,ctx->coeffD[k+(i-1)*nep->nt],w);
157:       }
158:     } else MatMultTranspose(ctx->D[i-1],z0,yy);
159:     VecPlaceArray(yyy,py+(i-2)*m);
160:     VecAXPY(yy,beta[i-1]*(1.0-sigma/xi[i-2]),yyy);
161:     VecResetArray(yyy);
162:     VecPlaceArray(xx,px+(i-1)*m);
163:     VecAXPY(yy,-1.0,xx);
164:     VecResetArray(xx);
165:     VecScale(yy,-1.0/(s[i-1]-sigma));
166:     VecResetArray(yy);
167:   }
168:   VecPlaceArray(yy,py+(d-1)*m);
169:   if (nep->fui==NEP_USER_INTERFACE_SPLIT) {
170:     VecZeroEntries(yy);
171:     for (k=0;k<nep->nt;k++) {
172:       MatMult(nep->A[k],z0,w);
173:       VecAXPY(yy,ctx->coeffD[k+d*nep->nt],w);
174:     }
175:   } else MatMultTranspose(ctx->D[d],z0,yy);
176:   VecScale(yy,-1.0/beta[d]);
177:   VecPlaceArray(yyy,py+(d-2)*m);
178:   VecAXPY(yy,beta[d-1]/xi[d-2],yyy);
179:   VecResetArray(yyy);
180:   VecResetArray(yy);

182:   for (i=d-2;i>0;i--) {
183:     VecPlaceArray(yyy,py+(i-1)*m);
184:     VecPlaceArray(yy,py+i*m);
185:     VecAXPY(yy,beta[i]/xi[i-1],yyy);
186:     VecResetArray(yyy);
187:     VecResetArray(yy);
188:   }

190:   VecRestoreArrayRead(x,&px);
191:   VecRestoreArray(y,&py);
192:   PetscFree(t);
193:   return 0;
194: }

196: static PetscErrorCode BackTransform_FullBasis(ST st,PetscInt n,PetscScalar *eigr,PetscScalar *eigi)
197: {
198:   NEP            nep;

200:   STShellGetContext(st,&nep);
201:   NEPNLEIGSBackTransform((PetscObject)nep,n,eigr,eigi);
202:   return 0;
203: }

205: static PetscErrorCode Apply_FullBasis(ST st,Vec x,Vec y)
206: {
207:   NEP            nep;
208:   NEP_NLEIGS     *ctx;

210:   STShellGetContext(st,&nep);
211:   ctx = (NEP_NLEIGS*)nep->data;
212:   MatMult(ctx->A,x,y);
213:   return 0;
214: }

216: static PetscErrorCode ApplyTranspose_FullBasis(ST st,Vec x,Vec y)
217: {
218:   NEP            nep;
219:   NEP_NLEIGS     *ctx;

221:   STShellGetContext(st,&nep);
222:   ctx = (NEP_NLEIGS*)nep->data;
223:   MatMultTranspose(ctx->A,x,y);
224:   return 0;
225: }

227: PetscErrorCode NEPSetUp_NLEIGS_FullBasis(NEP nep)
228: {
229:   NEP_NLEIGS     *ctx=(NEP_NLEIGS*)nep->data;
230:   ST             st;
231:   Mat            Q;
232:   PetscInt       i=0,deg=ctx->nmat-1;
233:   PetscBool      trackall,istrivial,ks;
234:   PetscScalar    *epsarray,*neparray;
235:   Vec            veps,w=NULL;
236:   EPSWhich       which;

239:   if (!ctx->eps) NEPNLEIGSGetEPS(nep,&ctx->eps);
240:   EPSGetST(ctx->eps,&st);
241:   EPSSetTarget(ctx->eps,nep->target);
242:   STSetDefaultShift(st,nep->target);
243:   if (!((PetscObject)(ctx->eps))->type_name) EPSSetType(ctx->eps,EPSKRYLOVSCHUR);
244:   else {
245:     PetscObjectTypeCompare((PetscObject)ctx->eps,EPSKRYLOVSCHUR,&ks);
247:   }
248:   STSetType(st,STSHELL);
249:   STShellSetContext(st,nep);
250:   STShellSetBackTransform(st,BackTransform_FullBasis);
251:   KSPGetOperators(ctx->ksp[0],&Q,NULL);
252:   MatCreateVecsEmpty(Q,&ctx->w[0],&ctx->w[1]);
253:   MatCreateVecsEmpty(Q,&ctx->w[2],&ctx->w[3]);
254:   MatCreateShell(PetscObjectComm((PetscObject)nep),deg*nep->nloc,deg*nep->nloc,deg*nep->n,deg*nep->n,nep,&ctx->A);
255:   MatShellSetOperation(ctx->A,MATOP_MULT,(void(*)(void))MatMult_FullBasis_Sinvert);
256:   MatShellSetOperation(ctx->A,MATOP_MULT_TRANSPOSE,(void(*)(void))MatMultTranspose_FullBasis_Sinvert);
257:   STShellSetApply(st,Apply_FullBasis);
258:   STShellSetApplyTranspose(st,ApplyTranspose_FullBasis);
259:   EPSSetOperators(ctx->eps,ctx->A,NULL);
260:   EPSSetProblemType(ctx->eps,EPS_NHEP);
261:   switch (nep->which) {
262:     case NEP_TARGET_MAGNITUDE:   which = EPS_TARGET_MAGNITUDE; break;
263:     case NEP_TARGET_REAL:        which = EPS_TARGET_REAL; break;
264:     case NEP_TARGET_IMAGINARY:   which = EPS_TARGET_IMAGINARY; break;
265:     case NEP_WHICH_USER:         which = EPS_WHICH_USER;
266:       EPSSetEigenvalueComparison(ctx->eps,nep->sc->comparison,nep->sc->comparisonctx);
267:       break;
268:     default: SETERRQ(PetscObjectComm((PetscObject)nep),PETSC_ERR_SUP,"Should set a target selection in NEPSetWhichEigenpairs()");
269:   }
270:   EPSSetWhichEigenpairs(ctx->eps,which);
271:   RGIsTrivial(nep->rg,&istrivial);
272:   if (!istrivial) EPSSetRG(ctx->eps,nep->rg);
273:   EPSSetDimensions(ctx->eps,nep->nev,nep->ncv,nep->mpd);
274:   EPSSetTolerances(ctx->eps,SlepcDefaultTol(nep->tol),nep->max_it);
275:   EPSSetTwoSided(ctx->eps,nep->twosided);
276:   /* Transfer the trackall option from pep to eps */
277:   NEPGetTrackAll(nep,&trackall);
278:   EPSSetTrackAll(ctx->eps,trackall);

280:   /* process initial vector */
281:   if (nep->nini<0) {
282:     VecCreateMPI(PetscObjectComm((PetscObject)ctx->eps),deg*nep->nloc,deg*nep->n,&veps);
283:     VecGetArray(veps,&epsarray);
284:     for (i=0;i<deg;i++) {
285:       if (i<-nep->nini) {
286:         VecGetArray(nep->IS[i],&neparray);
287:         PetscArraycpy(epsarray+i*nep->nloc,neparray,nep->nloc);
288:         VecRestoreArray(nep->IS[i],&neparray);
289:       } else {
290:         if (!w) VecDuplicate(nep->IS[0],&w);
291:         VecSetRandom(w,NULL);
292:         VecGetArray(w,&neparray);
293:         PetscArraycpy(epsarray+i*nep->nloc,neparray,nep->nloc);
294:         VecRestoreArray(w,&neparray);
295:       }
296:     }
297:     VecRestoreArray(veps,&epsarray);
298:     EPSSetInitialSpace(ctx->eps,1,&veps);
299:     VecDestroy(&veps);
300:     VecDestroy(&w);
301:     SlepcBasisDestroy_Private(&nep->nini,&nep->IS);
302:   }

304:   EPSSetUp(ctx->eps);
305:   EPSGetDimensions(ctx->eps,NULL,&nep->ncv,&nep->mpd);
306:   EPSGetTolerances(ctx->eps,NULL,&nep->max_it);
307:   NEPAllocateSolution(nep,0);
308:   return 0;
309: }

311: /*
312:    NEPNLEIGSExtract_None - Extracts the first block of the basis
313:    and normalizes the columns.
314: */
315: static PetscErrorCode NEPNLEIGSExtract_None(NEP nep,EPS eps)
316: {
317:   PetscInt          i,k,m,d;
318:   const PetscScalar *px;
319:   PetscScalar       sigma=nep->target,*b;
320:   Mat               A;
321:   Vec               xxr,xxi=NULL,w,t,xx;
322:   PetscReal         norm;
323:   NEP_NLEIGS        *ctx=(NEP_NLEIGS*)nep->data;

325:   d = ctx->nmat-1;
326:   EPSGetOperators(eps,&A,NULL);
327:   MatCreateVecs(A,&xxr,NULL);
328: #if !defined(PETSC_USE_COMPLEX)
329:   VecDuplicate(xxr,&xxi);
330: #endif
331:   w = nep->work[0];
332:   for (i=0;i<nep->nconv;i++) {
333:     EPSGetEigenvector(eps,i,xxr,xxi);
334:     VecGetArrayRead(xxr,&px);
335:     VecPlaceArray(w,px);
336:     BVInsertVec(nep->V,i,w);
337:     BVNormColumn(nep->V,i,NORM_2,&norm);
338:     BVScaleColumn(nep->V,i,1.0/norm);
339:     VecResetArray(w);
340:     VecRestoreArrayRead(xxr,&px);
341:   }
342:   if (nep->twosided) {
343:     PetscMalloc1(ctx->nmat,&b);
344:     NEPNLEIGSEvalNRTFunct(nep,d,sigma,b);
345:     m = nep->nloc;
346:     xx = ctx->w[0];
347:     w = nep->work[0]; t = nep->work[1];
348:     for (k=0;k<nep->nconv;k++) {
349:       EPSGetLeftEigenvector(eps,k,xxr,xxi);
350:       VecGetArrayRead(xxr,&px);
351:       VecPlaceArray(xx,px+(d-1)*m);
352:       VecCopy(xx,w);
353:       VecScale(w,PetscConj(b[d-1]));
354:       VecResetArray(xx);
355:       for (i=0;i<d-1;i++) {
356:         VecPlaceArray(xx,px+i*m);
357:         VecAXPY(w,PetscConj(b[i]),xx);
358:         VecResetArray(xx);
359:       }
360:       VecConjugate(w);
361:       KSPSolveTranspose(ctx->ksp[0],w,t);
362:       VecConjugate(t);
363:       BVInsertVec(nep->W,k,t);
364:       BVNormColumn(nep->W,k,NORM_2,&norm);
365:       BVScaleColumn(nep->W,k,1.0/norm);
366:       VecRestoreArrayRead(xxr,&px);
367:     }
368:     PetscFree(b);
369:   }
370:   VecDestroy(&xxr);
371: #if !defined(PETSC_USE_COMPLEX)
372:   VecDestroy(&xxi);
373: #endif
374:   return 0;
375: }

377: PetscErrorCode NEPSolve_NLEIGS_FullBasis(NEP nep)
378: {
379:   NEP_NLEIGS     *ctx = (NEP_NLEIGS*)nep->data;
380:   PetscInt       i;
381:   PetscScalar    eigi=0.0;

383:   EPSSolve(ctx->eps);
384:   EPSGetConverged(ctx->eps,&nep->nconv);
385:   EPSGetIterationNumber(ctx->eps,&nep->its);
386:   EPSGetConvergedReason(ctx->eps,(EPSConvergedReason*)&nep->reason);

388:   /* recover eigenvalues */
389:   for (i=0;i<nep->nconv;i++) {
390:     EPSGetEigenpair(ctx->eps,i,&nep->eigr[i],&eigi,NULL,NULL);
391: #if !defined(PETSC_USE_COMPLEX)
393: #endif
394:   }
395:   NEPNLEIGSExtract_None(nep,ctx->eps);
396:   return 0;
397: }

399: PetscErrorCode NEPNLEIGSSetEPS_NLEIGS(NEP nep,EPS eps)
400: {
401:   NEP_NLEIGS     *ctx=(NEP_NLEIGS*)nep->data;

403:   PetscObjectReference((PetscObject)eps);
404:   EPSDestroy(&ctx->eps);
405:   ctx->eps = eps;
406:   nep->state = NEP_STATE_INITIAL;
407:   return 0;
408: }

410: /*@
411:    NEPNLEIGSSetEPS - Associate an eigensolver object (EPS) to the NLEIGS solver.

413:    Collective on nep

415:    Input Parameters:
416: +  nep - nonlinear eigenvalue solver
417: -  eps - the eigensolver object

419:    Level: advanced

421: .seealso: NEPNLEIGSGetEPS()
422: @*/
423: PetscErrorCode NEPNLEIGSSetEPS(NEP nep,EPS eps)
424: {
428:   PetscTryMethod(nep,"NEPNLEIGSSetEPS_C",(NEP,EPS),(nep,eps));
429:   return 0;
430: }

432: static PetscErrorCode EPSMonitor_NLEIGS(EPS eps,PetscInt its,PetscInt nconv,PetscScalar *eigr,PetscScalar *eigi,PetscReal *errest,PetscInt nest,void *ctx)
433: {
434:   NEP            nep = (NEP)ctx;
435:   PetscInt       i,nv = PetscMin(nest,nep->ncv);

437:   for (i=0;i<nv;i++) {
438:     nep->eigr[i]   = eigr[i];
439:     nep->eigi[i]   = eigi[i];
440:     nep->errest[i] = errest[i];
441:   }
442:   NEPNLEIGSBackTransform((PetscObject)nep,nv,nep->eigr,nep->eigi);
443:   NEPMonitor(nep,its,nconv,nep->eigr,nep->eigi,nep->errest,nest);
444:   return 0;
445: }

447: PetscErrorCode NEPNLEIGSGetEPS_NLEIGS(NEP nep,EPS *eps)
448: {
449:   NEP_NLEIGS     *ctx=(NEP_NLEIGS*)nep->data;

451:   if (!ctx->eps) {
452:     EPSCreate(PetscObjectComm((PetscObject)nep),&ctx->eps);
453:     PetscObjectIncrementTabLevel((PetscObject)ctx->eps,(PetscObject)nep,1);
454:     EPSSetOptionsPrefix(ctx->eps,((PetscObject)nep)->prefix);
455:     EPSAppendOptionsPrefix(ctx->eps,"nep_nleigs_");
456:     PetscObjectSetOptions((PetscObject)ctx->eps,((PetscObject)nep)->options);
457:     EPSMonitorSet(ctx->eps,EPSMonitor_NLEIGS,nep,NULL);
458:   }
459:   *eps = ctx->eps;
460:   return 0;
461: }

463: /*@
464:    NEPNLEIGSGetEPS - Retrieve the eigensolver object (EPS) associated
465:    to the nonlinear eigenvalue solver.

467:    Not Collective

469:    Input Parameter:
470: .  nep - nonlinear eigenvalue solver

472:    Output Parameter:
473: .  eps - the eigensolver object

475:    Level: advanced

477: .seealso: NEPNLEIGSSetEPS()
478: @*/
479: PetscErrorCode NEPNLEIGSGetEPS(NEP nep,EPS *eps)
480: {
483:   PetscUseMethod(nep,"NEPNLEIGSGetEPS_C",(NEP,EPS*),(nep,eps));
484:   return 0;
485: }