Actual source code: nrefine.c

  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:    Newton refinement for polynomial eigenproblems.

 13:    References:

 15:        [1] T. Betcke and D. Kressner, "Perturbation, extraction and refinement
 16:            of invariant pairs for matrix polynomials", Linear Algebra Appl.
 17:            435(3):514-536, 2011.

 19:        [2] C. Campos and J.E. Roman, "Parallel iterative refinement in
 20:            polynomial eigenvalue problems", Numer. Linear Algebra Appl. 23(4):
 21:            730-745, 2016.
 22: */

 24: #include <slepc/private/pepimpl.h>
 25: #include <slepcblaslapack.h>

 27: typedef struct {
 28:   Mat          *A,M1;
 29:   BV           V,M2,M3,W;
 30:   PetscInt     k,nmat;
 31:   PetscScalar  *fih,*work,*M4;
 32:   PetscBLASInt *pM4;
 33:   PetscBool    compM1;
 34:   Vec          t;
 35: } PEP_REFINE_MATSHELL;

 37: typedef struct {
 38:   Mat          E[2],M1;
 39:   Vec          tN,ttN,t1,vseq;
 40:   VecScatter   scatterctx;
 41:   PetscBool    compM1;
 42:   PetscInt     *map0,*map1,*idxg,*idxp;
 43:   PetscSubcomm subc;
 44:   VecScatter   scatter_sub;
 45:   VecScatter   *scatter_id,*scatterp_id;
 46:   Mat          *A;
 47:   BV           V,W,M2,M3,Wt;
 48:   PetscScalar  *M4,*w,*wt,*d,*dt;
 49:   Vec          t,tg,Rv,Vi,tp,tpg;
 50:   PetscInt     idx,*cols;
 51: } PEP_REFINE_EXPLICIT;

 53: static PetscErrorCode MatMult_FS(Mat M ,Vec x,Vec y)
 54: {
 55:   PEP_REFINE_MATSHELL *ctx;
 56:   PetscInt            k,i;
 57:   PetscScalar         *c;
 58:   PetscBLASInt        k_,one=1;

 60:   PetscFunctionBegin;
 61:   PetscCall(MatShellGetContext(M,&ctx));
 62:   PetscCall(VecCopy(x,ctx->t));
 63:   k    = ctx->k;
 64:   c    = ctx->work;
 65:   PetscCall(PetscBLASIntCast(k,&k_));
 66:   PetscCall(MatMult(ctx->M1,x,y));
 67:   PetscCall(VecConjugate(ctx->t));
 68:   PetscCall(BVDotVec(ctx->M3,ctx->t,c));
 69:   for (i=0;i<k;i++) c[i] = PetscConj(c[i]);
 70:   PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
 71:   PetscCallLAPACKInfo("LAPACKgetrs",LAPACKgetrs_("N",&k_,&one,ctx->M4,&k_,ctx->pM4,c,&k_,&info));
 72:   PetscCall(PetscFPTrapPop());
 73:   PetscCall(BVMultVec(ctx->M2,-1.0,1.0,y,c));
 74:   PetscFunctionReturn(PETSC_SUCCESS);
 75: }

 77: /*
 78:   Evaluates the first d elements of the polynomial basis
 79:   on a given matrix H which is considered to be triangular
 80: */
 81: static PetscErrorCode PEPEvaluateBasisforMatrix(PEP pep,PetscInt nm,PetscInt k,PetscScalar *H,PetscInt ldh,PetscScalar *fH)
 82: {
 83:   PetscInt       i,j,ldfh=nm*k,off,nmat=pep->nmat;
 84:   PetscReal      *a=pep->pbc,*b=pep->pbc+nmat,*g=pep->pbc+2*nmat,t;
 85:   PetscScalar    corr=0.0,alpha,beta;
 86:   PetscBLASInt   k_,ldh_,ldfh_;

 88:   PetscFunctionBegin;
 89:   PetscCall(PetscBLASIntCast(ldh,&ldh_));
 90:   PetscCall(PetscBLASIntCast(k,&k_));
 91:   PetscCall(PetscBLASIntCast(ldfh,&ldfh_));
 92:   PetscCall(PetscArrayzero(fH,nm*k*k));
 93:   if (nm>0) for (j=0;j<k;j++) fH[j+j*ldfh] = 1.0;
 94:   if (nm>1) {
 95:     t = b[0]/a[0];
 96:     off = k;
 97:     for (j=0;j<k;j++) {
 98:       for (i=0;i<k;i++) fH[off+i+j*ldfh] = H[i+j*ldh]/a[0];
 99:       fH[j+j*ldfh] -= t;
100:     }
101:   }
102:   for (i=2;i<nm;i++) {
103:     off = i*k;
104:     if (i==2) {
105:       for (j=0;j<k;j++) {
106:         fH[off+j+j*ldfh] = 1.0;
107:         H[j+j*ldh] -= b[1];
108:       }
109:     } else {
110:       for (j=0;j<k;j++) {
111:         PetscCall(PetscArraycpy(fH+off+j*ldfh,fH+(i-2)*k+j*ldfh,k));
112:         H[j+j*ldh] += corr-b[i-1];
113:       }
114:     }
115:     corr  = b[i-1];
116:     beta  = -g[i-1]/a[i-1];
117:     alpha = 1/a[i-1];
118:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&alpha,H,&ldh_,fH+(i-1)*k,&ldfh_,&beta,fH+off,&ldfh_));
119:   }
120:   for (j=0;j<k;j++) H[j+j*ldh] += corr;
121:   PetscFunctionReturn(PETSC_SUCCESS);
122: }

124: static PetscErrorCode NRefSysSetup_shell(PEP pep,PetscInt k,PetscScalar *fH,PetscScalar *S,PetscInt lds,PetscScalar *fh,PetscScalar h,PEP_REFINE_MATSHELL *ctx)
125: {
126:   PetscScalar       *DHii,*T12,*Tr,*Ts,*array,s,ss,sone=1.0,zero=0.0,*M4=ctx->M4,t,*v,*T;
127:   const PetscScalar *m3,*m2;
128:   PetscInt          i,d,j,nmat=pep->nmat,lda=nmat*k,deg=nmat-1,nloc,ld2,ld3;
129:   PetscReal         *a=pep->pbc,*b=pep->pbc+nmat,*g=pep->pbc+2*nmat;
130:   PetscBLASInt      k_,lda_,lds_,nloc_,ld2_,one=1;
131:   Mat               *A=ctx->A,Mk,M1=ctx->M1,P;
132:   BV                V=ctx->V,M2=ctx->M2,M3=ctx->M3,W=ctx->W;
133:   MatStructure      str;
134:   Vec               vc;

136:   PetscFunctionBegin;
137:   PetscCall(STGetMatStructure(pep->st,&str));
138:   PetscCall(PetscMalloc3(nmat*k*k,&T12,k*k,&Tr,PetscMax(k*k,nmat),&Ts));
139:   DHii = T12;
140:   PetscCall(PetscArrayzero(DHii,k*k*nmat));
141:   for (i=0;i<k;i++) DHii[k+i+i*lda] = 1.0/a[0];
142:   for (d=2;d<nmat;d++) {
143:     for (j=0;j<k;j++) {
144:       for (i=0;i<k;i++) {
145:         DHii[d*k+i+j*lda] = ((h-b[d-1])*DHii[(d-1)*k+i+j*lda]+fH[(d-1)*k+i+j*lda]-g[d-1]*DHii[(d-2)*k+i+j*lda])/a[d-1];
146:       }
147:     }
148:   }
149:   /* T11 */
150:   if (!ctx->compM1) {
151:     PetscCall(MatCopy(A[0],M1,DIFFERENT_NONZERO_PATTERN));
152:     PetscCall(PEPEvaluateBasis(pep,h,0,Ts,NULL));
153:     for (j=1;j<nmat;j++) PetscCall(MatAXPY(M1,Ts[j],A[j],str));
154:   }

156:   /* T22 */
157:   PetscCall(PetscBLASIntCast(lds,&lds_));
158:   PetscCall(PetscBLASIntCast(k,&k_));
159:   PetscCall(PetscBLASIntCast(lda,&lda_));
160:   PetscCallBLAS("BLASgemm",BLASgemm_("C","N",&k_,&k_,&k_,&sone,S,&lds_,S,&lds_,&zero,Tr,&k_));
161:   for (i=1;i<deg;i++) {
162:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,Tr,&k_,DHii+i*k,&lda_,&zero,Ts,&k_));
163:     s = (i==1)?0.0:1.0;
164:     PetscCallBLAS("BLASgemm",BLASgemm_("C","N",&k_,&k_,&k_,&sone,fH+i*k,&lda_,Ts,&k_,&s,M4,&k_));
165:   }
166:   for (i=0;i<k;i++) for (j=0;j<i;j++) { t=M4[i+j*k];M4[i+j*k]=M4[j+i*k];M4[j+i*k]=t; }

168:   /* T12 */
169:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,NULL,&Mk));
170:   for (i=1;i<nmat;i++) {
171:     PetscCall(MatDenseGetArrayWrite(Mk,&array));
172:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,S,&lds_,DHii+i*k,&lda_,&zero,array,&k_));
173:     PetscCall(MatDenseRestoreArrayWrite(Mk,&array));
174:     PetscCall(BVSetActiveColumns(W,0,k));
175:     PetscCall(BVMult(W,1.0,0.0,V,Mk));
176:     if (i==1) PetscCall(BVMatMult(W,A[i],M2));
177:     else {
178:       PetscCall(BVMatMult(W,A[i],M3)); /* using M3 as work space */
179:       PetscCall(BVMult(M2,1.0,1.0,M3,NULL));
180:     }
181:   }

183:   /* T21 */
184:   PetscCall(MatDenseGetArrayWrite(Mk,&array));
185:   for (i=1;i<deg;i++) {
186:     s = (i==1)?0.0:1.0;
187:     ss = PetscConj(fh[i]);
188:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&ss,S,&lds_,fH+i*k,&lda_,&s,array,&k_));
189:   }
190:   PetscCall(MatDenseRestoreArrayWrite(Mk,&array));
191:   PetscCall(BVSetActiveColumns(M3,0,k));
192:   PetscCall(BVMult(M3,1.0,0.0,V,Mk));
193:   for (i=0;i<k;i++) {
194:     PetscCall(BVGetColumn(M3,i,&vc));
195:     PetscCall(VecConjugate(vc));
196:     PetscCall(BVRestoreColumn(M3,i,&vc));
197:   }
198:   PetscCall(MatDestroy(&Mk));
199:   PetscCall(PetscFree3(T12,Tr,Ts));

201:   PetscCall(VecGetLocalSize(ctx->t,&nloc));
202:   PetscCall(PetscBLASIntCast(nloc,&nloc_));
203:   PetscCall(PetscMalloc1(nloc*k,&T));
204:   PetscCall(KSPGetOperators(pep->refineksp,NULL,&P));
205:   if (!ctx->compM1) PetscCall(MatCopy(ctx->M1,P,SAME_NONZERO_PATTERN));
206:   PetscCall(BVGetArrayRead(ctx->M2,&m2));
207:   PetscCall(BVGetLeadingDimension(ctx->M2,&ld2));
208:   PetscCall(PetscBLASIntCast(ld2,&ld2_));
209:   PetscCall(BVGetArrayRead(ctx->M3,&m3));
210:   PetscCall(BVGetLeadingDimension(ctx->M3,&ld3));
211:   PetscCall(VecGetArray(ctx->t,&v));
212:   for (i=0;i<nloc;i++) for (j=0;j<k;j++) T[j+i*k] = m3[i+j*ld3];
213:   PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
214:   PetscCallLAPACKInfo("LAPACKgesv",LAPACKgesv_(&k_,&nloc_,ctx->M4,&k_,ctx->pM4,T,&k_,&info));
215:   PetscCall(PetscFPTrapPop());
216:   for (i=0;i<nloc;i++) v[i] = BLASdot_(&k_,m2+i,&ld2_,T+i*k,&one);
217:   PetscCall(VecRestoreArray(ctx->t,&v));
218:   PetscCall(BVRestoreArrayRead(ctx->M2,&m2));
219:   PetscCall(BVRestoreArrayRead(ctx->M3,&m3));
220:   PetscCall(MatDiagonalSet(P,ctx->t,ADD_VALUES));
221:   PetscCall(PetscFree(T));
222:   PetscCall(KSPSetUp(pep->refineksp));
223:   PetscFunctionReturn(PETSC_SUCCESS);
224: }

226: static PetscErrorCode NRefSysSolve_shell(KSP ksp,PetscInt nmat,Vec Rv,PetscScalar *Rh,PetscInt k,Vec dVi,PetscScalar *dHi)
227: {
228:   PetscScalar         *t0;
229:   PetscBLASInt        k_,one=1,lda_;
230:   PetscInt            i,lda=nmat*k;
231:   Mat                 M;
232:   PEP_REFINE_MATSHELL *ctx;

234:   PetscFunctionBegin;
235:   PetscCall(KSPGetOperators(ksp,&M,NULL));
236:   PetscCall(MatShellGetContext(M,&ctx));
237:   PetscCall(PetscCalloc1(k,&t0));
238:   PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
239:   PetscCall(PetscBLASIntCast(lda,&lda_));
240:   PetscCall(PetscBLASIntCast(k,&k_));
241:   for (i=0;i<k;i++) t0[i] = Rh[i];
242:   PetscCallLAPACKInfo("LAPACKgetrs",LAPACKgetrs_("N",&k_,&one,ctx->M4,&k_,ctx->pM4,t0,&k_,&info));
243:   PetscCall(BVMultVec(ctx->M2,-1.0,1.0,Rv,t0));
244:   PetscCall(KSPSolve(ksp,Rv,dVi));
245:   PetscCall(VecConjugate(dVi));
246:   PetscCall(BVDotVec(ctx->M3,dVi,dHi));
247:   PetscCall(VecConjugate(dVi));
248:   for (i=0;i<k;i++) dHi[i] = Rh[i]-PetscConj(dHi[i]);
249:   PetscCallLAPACKInfo("LAPACKgetrs",LAPACKgetrs_("N",&k_,&one,ctx->M4,&k_,ctx->pM4,dHi,&k_,&info));
250:   PetscCall(PetscFPTrapPop());
251:   PetscCall(PetscFree(t0));
252:   PetscFunctionReturn(PETSC_SUCCESS);
253: }

255: /*
256:    Computes the residual P(H,V*S)*e_j for the polynomial
257: */
258: static PetscErrorCode NRefRightSide(PetscInt nmat,PetscReal *pcf,Mat *A,PetscInt k,BV V,PetscScalar *S,PetscInt lds,PetscInt j,PetscScalar *H,PetscInt ldh,PetscScalar *fH,PetscScalar *DfH,PetscScalar *dH,BV dV,PetscScalar *dVS,PetscInt rds,Vec Rv,PetscScalar *Rh,BV W,Vec t)
259: {
260:   PetscScalar    *DS0,*DS1,*F,beta=0.0,sone=1.0,none=-1.0,tt=0.0,*h,zero=0.0,*Z,*c0;
261:   PetscReal      *a=pcf,*b=pcf+nmat,*g=b+nmat;
262:   PetscInt       i,ii,jj,lda;
263:   PetscBLASInt   lda_,k_,ldh_,lds_,nmat_,k2_,krds_,j_,one=1;
264:   Mat            M0;
265:   Vec            w;

267:   PetscFunctionBegin;
268:   PetscCall(PetscMalloc4(k*nmat,&h,k*k,&DS0,k*k,&DS1,k*k,&Z));
269:   lda = k*nmat;
270:   PetscCall(PetscBLASIntCast(k,&k_));
271:   PetscCall(PetscBLASIntCast(lds,&lds_));
272:   PetscCall(PetscBLASIntCast(lda,&lda_));
273:   PetscCall(PetscBLASIntCast(nmat,&nmat_));
274:   PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&nmat_,&k_,&sone,S,&lds_,fH+j*lda,&k_,&zero,h,&k_));
275:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,nmat,h,&M0));
276:   PetscCall(BVSetActiveColumns(W,0,nmat));
277:   PetscCall(BVMult(W,1.0,0.0,V,M0));
278:   PetscCall(MatDestroy(&M0));

280:   PetscCall(BVGetColumn(W,0,&w));
281:   PetscCall(MatMult(A[0],w,Rv));
282:   PetscCall(BVRestoreColumn(W,0,&w));
283:   for (i=1;i<nmat;i++) {
284:     PetscCall(BVGetColumn(W,i,&w));
285:     PetscCall(MatMult(A[i],w,t));
286:     PetscCall(BVRestoreColumn(W,i,&w));
287:     PetscCall(VecAXPY(Rv,1.0,t));
288:   }
289:   /* Update right-hand side */
290:   if (j) {
291:     PetscCall(PetscBLASIntCast(ldh,&ldh_));
292:     PetscCall(PetscArrayzero(Z,k*k));
293:     PetscCall(PetscArrayzero(DS0,k*k));
294:     PetscCall(PetscArraycpy(Z+(j-1)*k,dH+(j-1)*k,k));
295:     /* Update DfH */
296:     for (i=1;i<nmat;i++) {
297:       if (i>1) {
298:         beta = -g[i-1];
299:         PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,fH+(i-1)*k,&lda_,Z,&k_,&beta,DS0,&k_));
300:         tt += -b[i-1];
301:         for (ii=0;ii<k;ii++) H[ii+ii*ldh] += tt;
302:         tt = b[i-1];
303:         beta = 1.0/a[i-1];
304:         PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&beta,DS1,&k_,H,&ldh_,&beta,DS0,&k_));
305:         F = DS0; DS0 = DS1; DS1 = F;
306:       } else {
307:         PetscCall(PetscArrayzero(DS1,k*k));
308:         for (ii=0;ii<k;ii++) DS1[ii+(j-1)*k] = Z[ii+(j-1)*k]/a[0];
309:       }
310:       for (jj=j;jj<k;jj++) {
311:         for (ii=0;ii<k;ii++) DfH[k*i+ii+jj*lda] += DS1[ii+jj*k];
312:       }
313:     }
314:     for (ii=0;ii<k;ii++) H[ii+ii*ldh] += tt;
315:     /* Update right-hand side */
316:     PetscCall(PetscBLASIntCast(2*k,&k2_));
317:     PetscCall(PetscBLASIntCast(j,&j_));
318:     PetscCall(PetscBLASIntCast(k+rds,&krds_));
319:     c0 = DS0;
320:     PetscCall(PetscArrayzero(Rh,k));
321:     for (i=0;i<nmat;i++) {
322:       PetscCallBLAS("BLASgemv",BLASgemv_("N",&krds_,&j_,&sone,dVS,&k2_,fH+j*lda+i*k,&one,&zero,h,&one));
323:       PetscCallBLAS("BLASgemv",BLASgemv_("N",&k_,&k_,&sone,S,&lds_,DfH+i*k+j*lda,&one,&sone,h,&one));
324:       PetscCall(BVMultVec(V,1.0,0.0,t,h));
325:       PetscCall(BVSetActiveColumns(dV,0,rds));
326:       PetscCall(BVMultVec(dV,1.0,1.0,t,h+k));
327:       PetscCall(BVGetColumn(W,i,&w));
328:       PetscCall(MatMult(A[i],t,w));
329:       PetscCall(BVRestoreColumn(W,i,&w));
330:       if (i>0 && i<nmat-1) {
331:         PetscCallBLAS("BLASgemv",BLASgemv_("C",&k_,&k_,&sone,S,&lds_,h,&one,&zero,c0,&one));
332:         PetscCallBLAS("BLASgemv",BLASgemv_("C",&k_,&k_,&none,fH+i*k,&lda_,c0,&one,&sone,Rh,&one));
333:       }
334:     }

336:     for (i=0;i<nmat;i++) h[i] = -1.0;
337:     PetscCall(BVMultVec(W,1.0,1.0,Rv,h));
338:   }
339:   PetscCall(PetscFree4(h,DS0,DS1,Z));
340:   PetscFunctionReturn(PETSC_SUCCESS);
341: }

343: static PetscErrorCode NRefSysSolve_mbe(PetscInt k,PetscInt sz,BV W,PetscScalar *w,BV Wt,PetscScalar *wt,PetscScalar *d,PetscScalar *dt,KSP ksp,BV T2,BV T3 ,PetscScalar *T4,PetscBool trans,Vec x1,PetscScalar *x2,Vec sol1,PetscScalar *sol2,Vec vw)
344: {
345:   PetscInt       i,j,incf,incc;
346:   PetscScalar    *y,*g,*xx2,*ww,y2,*dd;
347:   Vec            v,t,xx1;
348:   BV             WW,T;

350:   PetscFunctionBegin;
351:   PetscCall(PetscMalloc3(sz,&y,sz,&g,k,&xx2));
352:   if (trans) {
353:     WW = W; ww = w; dd = d; T = T3; incf = 0; incc = 1;
354:   } else {
355:     WW = Wt; ww = wt; dd = dt; T = T2; incf = 1; incc = 0;
356:   }
357:   xx1 = vw;
358:   PetscCall(VecCopy(x1,xx1));
359:   PetscCall(PetscArraycpy(xx2,x2,sz));
360:   PetscCall(PetscArrayzero(sol2,k));
361:   for (i=sz-1;i>=0;i--) {
362:     PetscCall(BVGetColumn(WW,i,&v));
363:     PetscCall(VecConjugate(v));
364:     PetscCall(VecDot(xx1,v,y+i));
365:     PetscCall(VecConjugate(v));
366:     PetscCall(BVRestoreColumn(WW,i,&v));
367:     for (j=0;j<i;j++) y[i] += ww[j+i*k]*xx2[j];
368:     y[i] = -(y[i]-xx2[i])/dd[i];
369:     PetscCall(BVGetColumn(T,i,&t));
370:     PetscCall(VecAXPY(xx1,-y[i],t));
371:     PetscCall(BVRestoreColumn(T,i,&t));
372:     for (j=0;j<=i;j++) xx2[j] -= y[i]*T4[j*incf+incc*i+(i*incf+incc*j)*k];
373:     g[i] = xx2[i];
374:   }
375:   if (trans) PetscCall(KSPSolveTranspose(ksp,xx1,sol1));
376:   else PetscCall(KSPSolve(ksp,xx1,sol1));
377:   if (trans) {
378:     WW = Wt; ww = wt; dd = dt; T = T2; incf = 1; incc = 0;
379:   } else {
380:     WW = W; ww = w; dd = d; T = T3; incf = 0; incc = 1;
381:   }
382:   for (i=0;i<sz;i++) {
383:     PetscCall(BVGetColumn(T,i,&t));
384:     PetscCall(VecConjugate(t));
385:     PetscCall(VecDot(sol1,t,&y2));
386:     PetscCall(VecConjugate(t));
387:     PetscCall(BVRestoreColumn(T,i,&t));
388:     for (j=0;j<i;j++) y2 += sol2[j]*T4[j*incf+incc*i+(i*incf+incc*j)*k];
389:     y2 = (g[i]-y2)/dd[i];
390:     PetscCall(BVGetColumn(WW,i,&v));
391:     PetscCall(VecAXPY(sol1,-y2,v));
392:     for (j=0;j<i;j++) sol2[j] -= ww[j+i*k]*y2;
393:     sol2[i] = y[i]+y2;
394:     PetscCall(BVRestoreColumn(WW,i,&v));
395:   }
396:   PetscCall(PetscFree3(y,g,xx2));
397:   PetscFunctionReturn(PETSC_SUCCESS);
398: }

400: static PetscErrorCode NRefSysSetup_mbe(PEP pep,PetscInt k,KSP ksp,PetscScalar *fH,PetscScalar *S,PetscInt lds,PetscScalar *fh,PetscScalar h,BV V,PEP_REFINE_EXPLICIT *matctx)
401: {
402:   PetscInt       i,j,l,nmat=pep->nmat,lda=nmat*k,deg=nmat-1;
403:   Mat            M1=matctx->M1,*A,*At,Mk;
404:   PetscReal      *a=pep->pbc,*b=pep->pbc+nmat,*g=pep->pbc+2*nmat;
405:   PetscScalar    s,ss,*DHii,*T12,*array,*Ts,*Tr,*M4=matctx->M4,sone=1.0,zero=0.0;
406:   PetscScalar    *w=matctx->w,*wt=matctx->wt,*d=matctx->d,*dt=matctx->dt;
407:   PetscBLASInt   lds_,lda_,k_;
408:   MatStructure   str;
409:   PetscBool      flg;
410:   BV             M2=matctx->M2,M3=matctx->M3,W=matctx->W,Wt=matctx->Wt;
411:   Vec            vc,vc2;

413:   PetscFunctionBegin;
414:   PetscCall(PetscMalloc3(nmat*k*k,&T12,k*k,&Tr,PetscMax(k*k,nmat),&Ts));
415:   PetscCall(STGetMatStructure(pep->st,&str));
416:   PetscCall(STGetTransform(pep->st,&flg));
417:   if (flg) {
418:     PetscCall(PetscMalloc1(pep->nmat,&At));
419:     for (i=0;i<pep->nmat;i++) PetscCall(STGetMatrixTransformed(pep->st,i,&At[i]));
420:   } else At = pep->A;
421:   if (matctx->subc) A = matctx->A;
422:   else A = At;
423:   /* Form the explicit system matrix */
424:   DHii = T12;
425:   PetscCall(PetscArrayzero(DHii,k*k*nmat));
426:   for (i=0;i<k;i++) DHii[k+i+i*lda] = 1.0/a[0];
427:   for (l=2;l<nmat;l++) {
428:     for (j=0;j<k;j++) {
429:       for (i=0;i<k;i++) {
430:         DHii[l*k+i+j*lda] = ((h-b[l-1])*DHii[(l-1)*k+i+j*lda]+fH[(l-1)*k+i+j*lda]-g[l-1]*DHii[(l-2)*k+i+j*lda])/a[l-1];
431:       }
432:     }
433:   }

435:   /* T11 */
436:   if (!matctx->compM1) {
437:     PetscCall(MatCopy(A[0],M1,DIFFERENT_NONZERO_PATTERN));
438:     PetscCall(PEPEvaluateBasis(pep,h,0,Ts,NULL));
439:     for (j=1;j<nmat;j++) PetscCall(MatAXPY(M1,Ts[j],A[j],str));
440:   }

442:   /* T22 */
443:   PetscCall(PetscBLASIntCast(lds,&lds_));
444:   PetscCall(PetscBLASIntCast(k,&k_));
445:   PetscCall(PetscBLASIntCast(lda,&lda_));
446:   PetscCallBLAS("BLASgemm",BLASgemm_("C","N",&k_,&k_,&k_,&sone,S,&lds_,S,&lds_,&zero,Tr,&k_));
447:   for (i=1;i<deg;i++) {
448:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,Tr,&k_,DHii+i*k,&lda_,&zero,Ts,&k_));
449:     s = (i==1)?0.0:1.0;
450:     PetscCallBLAS("BLASgemm",BLASgemm_("C","N",&k_,&k_,&k_,&sone,fH+i*k,&lda_,Ts,&k_,&s,M4,&k_));
451:   }

453:   /* T12 */
454:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,NULL,&Mk));
455:   for (i=1;i<nmat;i++) {
456:     PetscCall(MatDenseGetArrayWrite(Mk,&array));
457:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,S,&lds_,DHii+i*k,&lda_,&zero,array,&k_));
458:     PetscCall(MatDenseRestoreArrayWrite(Mk,&array));
459:     PetscCall(BVSetActiveColumns(W,0,k));
460:     PetscCall(BVMult(W,1.0,0.0,V,Mk));
461:     if (i==1) PetscCall(BVMatMult(W,A[i],M2));
462:     else {
463:       PetscCall(BVMatMult(W,A[i],M3)); /* using M3 as work space */
464:       PetscCall(BVMult(M2,1.0,1.0,M3,NULL));
465:     }
466:   }

468:   /* T21 */
469:   PetscCall(MatDenseGetArrayWrite(Mk,&array));
470:   for (i=1;i<deg;i++) {
471:     s = (i==1)?0.0:1.0;
472:     ss = PetscConj(fh[i]);
473:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&ss,S,&lds_,fH+i*k,&lda_,&s,array,&k_));
474:   }
475:   PetscCall(MatDenseRestoreArrayWrite(Mk,&array));
476:   PetscCall(BVSetActiveColumns(M3,0,k));
477:   PetscCall(BVMult(M3,1.0,0.0,V,Mk));
478:   for (i=0;i<k;i++) {
479:     PetscCall(BVGetColumn(M3,i,&vc));
480:     PetscCall(VecConjugate(vc));
481:     PetscCall(BVRestoreColumn(M3,i,&vc));
482:   }

484:   PetscCall(PEP_KSPSetOperators(ksp,M1,M1));
485:   PetscCall(KSPSetUp(ksp));
486:   PetscCall(MatDestroy(&Mk));

488:   /* Set up for BEMW */
489:   for (i=0;i<k;i++) {
490:     PetscCall(BVGetColumn(M2,i,&vc));
491:     PetscCall(BVGetColumn(W,i,&vc2));
492:     PetscCall(NRefSysSolve_mbe(k,i,W,w,Wt,wt,d,dt,ksp,M2,M3,M4,PETSC_FALSE,vc,M4+i*k,vc2,w+i*k,matctx->t));
493:     PetscCall(BVRestoreColumn(M2,i,&vc));
494:     PetscCall(BVGetColumn(M3,i,&vc));
495:     PetscCall(VecConjugate(vc));
496:     PetscCall(VecDot(vc2,vc,&d[i]));
497:     PetscCall(VecConjugate(vc));
498:     PetscCall(BVRestoreColumn(M3,i,&vc));
499:     for (j=0;j<i;j++) d[i] += M4[i+j*k]*w[j+i*k];
500:     d[i] = M4[i+i*k]-d[i];
501:     PetscCall(BVRestoreColumn(W,i,&vc2));

503:     PetscCall(BVGetColumn(M3,i,&vc));
504:     PetscCall(BVGetColumn(Wt,i,&vc2));
505:     for (j=0;j<=i;j++) Ts[j] = M4[i+j*k];
506:     PetscCall(NRefSysSolve_mbe(k,i,W,w,Wt,wt,d,dt,ksp,M2,M3,M4,PETSC_TRUE,vc,Ts,vc2,wt+i*k,matctx->t));
507:     PetscCall(BVRestoreColumn(M3,i,&vc));
508:     PetscCall(BVGetColumn(M2,i,&vc));
509:     PetscCall(VecConjugate(vc2));
510:     PetscCall(VecDot(vc,vc2,&dt[i]));
511:     PetscCall(VecConjugate(vc2));
512:     PetscCall(BVRestoreColumn(M2,i,&vc));
513:     for (j=0;j<i;j++) dt[i] += M4[j+i*k]*wt[j+i*k];
514:     dt[i] = M4[i+i*k]-dt[i];
515:     PetscCall(BVRestoreColumn(Wt,i,&vc2));
516:   }

518:   if (flg) PetscCall(PetscFree(At));
519:   PetscCall(PetscFree3(T12,Tr,Ts));
520:   PetscFunctionReturn(PETSC_SUCCESS);
521: }

523: static PetscErrorCode NRefSysSetup_explicit(PEP pep,PetscInt k,KSP ksp,PetscScalar *fH,PetscScalar *S,PetscInt lds,PetscScalar *fh,PetscScalar h,BV V,PEP_REFINE_EXPLICIT *matctx,BV W)
524: {
525:   PetscInt          i,j,d,n,n0,m0,n1,m1,nmat=pep->nmat,lda=nmat*k,deg=nmat-1;
526:   PetscInt          *idxg=matctx->idxg,*idxp=matctx->idxp,idx,ncols;
527:   Mat               M,*E=matctx->E,*A,*At,Mk,Md;
528:   PetscReal         *a=pep->pbc,*b=pep->pbc+nmat,*g=pep->pbc+2*nmat;
529:   PetscScalar       s,ss,*DHii,*T22,*T21,*T12,*Ts,*Tr,*array,*ts,sone=1.0,zero=0.0;
530:   PetscBLASInt      lds_,lda_,k_;
531:   const PetscInt    *idxmc;
532:   const PetscScalar *valsc,*carray;
533:   MatStructure      str;
534:   Vec               vc,vc0;
535:   PetscBool         flg;

537:   PetscFunctionBegin;
538:   PetscCall(PetscMalloc5(k*k,&T22,k*k,&T21,nmat*k*k,&T12,k*k,&Tr,k*k,&Ts));
539:   PetscCall(STGetMatStructure(pep->st,&str));
540:   PetscCall(KSPGetOperators(ksp,&M,NULL));
541:   PetscCall(MatGetOwnershipRange(E[1],&n1,&m1));
542:   PetscCall(MatGetOwnershipRange(E[0],&n0,&m0));
543:   PetscCall(MatGetOwnershipRange(M,&n,NULL));
544:   PetscCall(PetscMalloc1(nmat,&ts));
545:   PetscCall(STGetTransform(pep->st,&flg));
546:   if (flg) {
547:     PetscCall(PetscMalloc1(pep->nmat,&At));
548:     for (i=0;i<pep->nmat;i++) PetscCall(STGetMatrixTransformed(pep->st,i,&At[i]));
549:   } else At = pep->A;
550:   if (matctx->subc) A = matctx->A;
551:   else A = At;
552:   /* Form the explicit system matrix */
553:   DHii = T12;
554:   PetscCall(PetscArrayzero(DHii,k*k*nmat));
555:   for (i=0;i<k;i++) DHii[k+i+i*lda] = 1.0/a[0];
556:   for (d=2;d<nmat;d++) {
557:     for (j=0;j<k;j++) {
558:       for (i=0;i<k;i++) {
559:         DHii[d*k+i+j*lda] = ((h-b[d-1])*DHii[(d-1)*k+i+j*lda]+fH[(d-1)*k+i+j*lda]-g[d-1]*DHii[(d-2)*k+i+j*lda])/a[d-1];
560:       }
561:     }
562:   }

564:   /* T11 */
565:   if (!matctx->compM1) {
566:     PetscCall(MatCopy(A[0],E[0],DIFFERENT_NONZERO_PATTERN));
567:     PetscCall(PEPEvaluateBasis(pep,h,0,Ts,NULL));
568:     for (j=1;j<nmat;j++) PetscCall(MatAXPY(E[0],Ts[j],A[j],str));
569:   }
570:   for (i=n0;i<m0;i++) {
571:     PetscCall(MatGetRow(E[0],i,&ncols,&idxmc,&valsc));
572:     idx = n+i-n0;
573:     for (j=0;j<ncols;j++) {
574:       idxg[j] = matctx->map0[idxmc[j]];
575:     }
576:     PetscCall(MatSetValues(M,1,&idx,ncols,idxg,valsc,INSERT_VALUES));
577:     PetscCall(MatRestoreRow(E[0],i,&ncols,&idxmc,&valsc));
578:   }

580:   /* T22 */
581:   PetscCall(PetscBLASIntCast(lds,&lds_));
582:   PetscCall(PetscBLASIntCast(k,&k_));
583:   PetscCall(PetscBLASIntCast(lda,&lda_));
584:   PetscCallBLAS("BLASgemm",BLASgemm_("C","N",&k_,&k_,&k_,&sone,S,&lds_,S,&lds_,&zero,Tr,&k_));
585:   for (i=1;i<deg;i++) {
586:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,Tr,&k_,DHii+i*k,&lda_,&zero,Ts,&k_));
587:     s = (i==1)?0.0:1.0;
588:     PetscCallBLAS("BLASgemm",BLASgemm_("C","N",&k_,&k_,&k_,&sone,fH+i*k,&lda_,Ts,&k_,&s,T22,&k_));
589:   }
590:   for (j=0;j<k;j++) idxp[j] = matctx->map1[j];
591:   for (i=0;i<m1-n1;i++) {
592:     idx = n+m0-n0+i;
593:     for (j=0;j<k;j++) {
594:       Tr[j] = T22[n1+i+j*k];
595:     }
596:     PetscCall(MatSetValues(M,1,&idx,k,idxp,Tr,INSERT_VALUES));
597:   }

599:   /* T21 */
600:   for (i=1;i<deg;i++) {
601:     s = (i==1)?0.0:1.0;
602:     ss = PetscConj(fh[i]);
603:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&ss,S,&lds_,fH+i*k,&lda_,&s,T21,&k_));
604:   }
605:   PetscCall(BVSetActiveColumns(W,0,k));
606:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,T21,&Mk));
607:   PetscCall(BVMult(W,1.0,0.0,V,Mk));
608:   for (i=0;i<k;i++) {
609:     PetscCall(BVGetColumn(W,i,&vc));
610:     PetscCall(VecConjugate(vc));
611:     PetscCall(VecGetArrayRead(vc,&carray));
612:     idx = matctx->map1[i];
613:     PetscCall(MatSetValues(M,1,&idx,m0-n0,matctx->map0+n0,carray,INSERT_VALUES));
614:     PetscCall(VecRestoreArrayRead(vc,&carray));
615:     PetscCall(BVRestoreColumn(W,i,&vc));
616:   }

618:   /* T12 */
619:   for (i=1;i<nmat;i++) {
620:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,S,&lds_,DHii+i*k,&lda_,&zero,Ts,&k_));
621:     for (j=0;j<k;j++) PetscCall(PetscArraycpy(T12+i*k+j*lda,Ts+j*k,k));
622:   }
623:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,nmat-1,NULL,&Md));
624:   for (i=0;i<nmat;i++) ts[i] = 1.0;
625:   for (j=0;j<k;j++) {
626:     PetscCall(MatDenseGetArrayWrite(Md,&array));
627:     PetscCall(PetscArraycpy(array,T12+k+j*lda,(nmat-1)*k));
628:     PetscCall(MatDenseRestoreArrayWrite(Md,&array));
629:     PetscCall(BVSetActiveColumns(W,0,nmat-1));
630:     PetscCall(BVMult(W,1.0,0.0,V,Md));
631:     for (i=nmat-1;i>0;i--) {
632:       PetscCall(BVGetColumn(W,i-1,&vc0));
633:       PetscCall(BVGetColumn(W,i,&vc));
634:       PetscCall(MatMult(A[i],vc0,vc));
635:       PetscCall(BVRestoreColumn(W,i-1,&vc0));
636:       PetscCall(BVRestoreColumn(W,i,&vc));
637:     }
638:     PetscCall(BVSetActiveColumns(W,1,nmat));
639:     PetscCall(BVGetColumn(W,0,&vc0));
640:     PetscCall(BVMultVec(W,1.0,0.0,vc0,ts));
641:     PetscCall(VecGetArrayRead(vc0,&carray));
642:     idx = matctx->map1[j];
643:     PetscCall(MatSetValues(M,m0-n0,matctx->map0+n0,1,&idx,carray,INSERT_VALUES));
644:     PetscCall(VecRestoreArrayRead(vc0,&carray));
645:     PetscCall(BVRestoreColumn(W,0,&vc0));
646:   }
647:   PetscCall(MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY));
648:   PetscCall(MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY));
649:   PetscCall(PEP_KSPSetOperators(ksp,M,M));
650:   PetscCall(KSPSetUp(ksp));
651:   PetscCall(PetscFree(ts));
652:   PetscCall(MatDestroy(&Mk));
653:   PetscCall(MatDestroy(&Md));
654:   if (flg) PetscCall(PetscFree(At));
655:   PetscCall(PetscFree5(T22,T21,T12,Tr,Ts));
656:   PetscFunctionReturn(PETSC_SUCCESS);
657: }

659: static PetscErrorCode NRefSysSolve_explicit(PetscInt k,KSP ksp,Vec Rv,PetscScalar *Rh,Vec dVi,PetscScalar *dHi,PEP_REFINE_EXPLICIT *matctx)
660: {
661:   PetscInt          n0,m0,n1,m1,i;
662:   PetscScalar       *arrayV;
663:   const PetscScalar *array;

665:   PetscFunctionBegin;
666:   PetscCall(MatGetOwnershipRange(matctx->E[1],&n1,&m1));
667:   PetscCall(MatGetOwnershipRange(matctx->E[0],&n0,&m0));

669:   /* Right side */
670:   PetscCall(VecGetArrayRead(Rv,&array));
671:   PetscCall(VecSetValues(matctx->tN,m0-n0,matctx->map0+n0,array,INSERT_VALUES));
672:   PetscCall(VecRestoreArrayRead(Rv,&array));
673:   PetscCall(VecSetValues(matctx->tN,m1-n1,matctx->map1+n1,Rh+n1,INSERT_VALUES));
674:   PetscCall(VecAssemblyBegin(matctx->tN));
675:   PetscCall(VecAssemblyEnd(matctx->tN));

677:   /* Solve */
678:   PetscCall(KSPSolve(ksp,matctx->tN,matctx->ttN));

680:   /* Retrieve solution */
681:   PetscCall(VecGetArray(dVi,&arrayV));
682:   PetscCall(VecGetArrayRead(matctx->ttN,&array));
683:   PetscCall(PetscArraycpy(arrayV,array,m0-n0));
684:   PetscCall(VecRestoreArray(dVi,&arrayV));
685:   if (!matctx->subc) {
686:     PetscCall(VecGetArray(matctx->t1,&arrayV));
687:     for (i=0;i<m1-n1;i++) arrayV[i] =  array[m0-n0+i];
688:     PetscCall(VecRestoreArray(matctx->t1,&arrayV));
689:     PetscCall(VecRestoreArrayRead(matctx->ttN,&array));
690:     PetscCall(VecScatterBegin(matctx->scatterctx,matctx->t1,matctx->vseq,INSERT_VALUES,SCATTER_FORWARD));
691:     PetscCall(VecScatterEnd(matctx->scatterctx,matctx->t1,matctx->vseq,INSERT_VALUES,SCATTER_FORWARD));
692:     PetscCall(VecGetArrayRead(matctx->vseq,&array));
693:     for (i=0;i<k;i++) dHi[i] = array[i];
694:     PetscCall(VecRestoreArrayRead(matctx->vseq,&array));
695:   }
696:   PetscFunctionReturn(PETSC_SUCCESS);
697: }

699: static PetscErrorCode NRefSysIter(PetscInt i,PEP pep,PetscInt k,KSP ksp,PetscScalar *fH,PetscScalar *S,PetscInt lds,PetscScalar *fh,PetscScalar *H,PetscInt ldh,Vec Rv,PetscScalar *Rh,BV V,Vec dVi,PetscScalar *dHi,PEP_REFINE_EXPLICIT *matctx,BV W)
700: {
701:   PetscInt            j,m,lda=pep->nmat*k,n0,m0,idx;
702:   PetscMPIInt         root,len;
703:   PetscScalar         *array2,h;
704:   const PetscScalar   *array;
705:   Vec                 R,Vi;
706:   PEP_REFINE_MATSHELL *ctx;
707:   Mat                 M;

709:   PetscFunctionBegin;
710:   if (!matctx || !matctx->subc) {
711:     for (j=0;j<pep->nmat;j++) fh[j] = fH[j*k+i+i*lda];
712:     h   = H[i+i*ldh];
713:     idx = i;
714:     R   = Rv;
715:     Vi  = dVi;
716:     switch (pep->scheme) {
717:     case PEP_REFINE_SCHEME_EXPLICIT:
718:       PetscCall(NRefSysSetup_explicit(pep,k,ksp,fH,S,lds,fh,h,V,matctx,W));
719:       matctx->compM1 = PETSC_FALSE;
720:       break;
721:     case PEP_REFINE_SCHEME_MBE:
722:       PetscCall(NRefSysSetup_mbe(pep,k,ksp,fH,S,lds,fh,h,V,matctx));
723:       matctx->compM1 = PETSC_FALSE;
724:       break;
725:     case PEP_REFINE_SCHEME_SCHUR:
726:       PetscCall(KSPGetOperators(ksp,&M,NULL));
727:       PetscCall(MatShellGetContext(M,&ctx));
728:       PetscCall(NRefSysSetup_shell(pep,k,fH,S,lds,fh,h,ctx));
729:       ctx->compM1 = PETSC_FALSE;
730:       break;
731:     }
732:   } else {
733:     if (i%matctx->subc->n==0 && (idx=i+matctx->subc->color)<k) {
734:       for (j=0;j<pep->nmat;j++) fh[j] = fH[j*k+idx+idx*lda];
735:       h = H[idx+idx*ldh];
736:       matctx->idx = idx;
737:       switch (pep->scheme) {
738:       case PEP_REFINE_SCHEME_EXPLICIT:
739:         PetscCall(NRefSysSetup_explicit(pep,k,ksp,fH,S,lds,fh,h,matctx->V,matctx,matctx->W));
740:         matctx->compM1 = PETSC_FALSE;
741:         break;
742:       case PEP_REFINE_SCHEME_MBE:
743:         PetscCall(NRefSysSetup_mbe(pep,k,ksp,fH,S,lds,fh,h,matctx->V,matctx));
744:         matctx->compM1 = PETSC_FALSE;
745:         break;
746:       case PEP_REFINE_SCHEME_SCHUR:
747:         break;
748:       }
749:     } else idx = matctx->idx;
750:     PetscCall(VecScatterBegin(matctx->scatter_id[i%matctx->subc->n],Rv,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
751:     PetscCall(VecScatterEnd(matctx->scatter_id[i%matctx->subc->n],Rv,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
752:     PetscCall(VecGetArrayRead(matctx->tg,&array));
753:     PetscCall(VecPlaceArray(matctx->t,array));
754:     PetscCall(VecCopy(matctx->t,matctx->Rv));
755:     PetscCall(VecResetArray(matctx->t));
756:     PetscCall(VecRestoreArrayRead(matctx->tg,&array));
757:     R  = matctx->Rv;
758:     Vi = matctx->Vi;
759:   }
760:   if (idx==i && idx<k) {
761:     switch (pep->scheme) {
762:       case PEP_REFINE_SCHEME_EXPLICIT:
763:         PetscCall(NRefSysSolve_explicit(k,ksp,R,Rh,Vi,dHi,matctx));
764:         break;
765:       case PEP_REFINE_SCHEME_MBE:
766:         PetscCall(NRefSysSolve_mbe(k,k,matctx->W,matctx->w,matctx->Wt,matctx->wt,matctx->d,matctx->dt,ksp,matctx->M2,matctx->M3 ,matctx->M4,PETSC_FALSE,R,Rh,Vi,dHi,matctx->t));
767:         break;
768:       case PEP_REFINE_SCHEME_SCHUR:
769:         PetscCall(NRefSysSolve_shell(ksp,pep->nmat,R,Rh,k,Vi,dHi));
770:         break;
771:     }
772:   }
773:   if (matctx && matctx->subc) {
774:     PetscCall(VecGetLocalSize(Vi,&m));
775:     PetscCall(VecGetArrayRead(Vi,&array));
776:     PetscCall(VecGetArray(matctx->tg,&array2));
777:     PetscCall(PetscArraycpy(array2,array,m));
778:     PetscCall(VecRestoreArray(matctx->tg,&array2));
779:     PetscCall(VecRestoreArrayRead(Vi,&array));
780:     PetscCall(VecScatterBegin(matctx->scatter_id[i%matctx->subc->n],matctx->tg,dVi,INSERT_VALUES,SCATTER_REVERSE));
781:     PetscCall(VecScatterEnd(matctx->scatter_id[i%matctx->subc->n],matctx->tg,dVi,INSERT_VALUES,SCATTER_REVERSE));
782:     switch (pep->scheme) {
783:     case PEP_REFINE_SCHEME_EXPLICIT:
784:       PetscCall(MatGetOwnershipRange(matctx->E[0],&n0,&m0));
785:       PetscCall(VecGetArrayRead(matctx->ttN,&array));
786:       PetscCall(VecPlaceArray(matctx->tp,array+m0-n0));
787:       PetscCall(VecScatterBegin(matctx->scatterp_id[i%matctx->subc->n],matctx->tp,matctx->tpg,INSERT_VALUES,SCATTER_FORWARD));
788:       PetscCall(VecScatterEnd(matctx->scatterp_id[i%matctx->subc->n],matctx->tp,matctx->tpg,INSERT_VALUES,SCATTER_FORWARD));
789:       PetscCall(VecResetArray(matctx->tp));
790:       PetscCall(VecRestoreArrayRead(matctx->ttN,&array));
791:       PetscCall(VecGetArrayRead(matctx->tpg,&array));
792:       for (j=0;j<k;j++) dHi[j] = array[j];
793:       PetscCall(VecRestoreArrayRead(matctx->tpg,&array));
794:       break;
795:      case PEP_REFINE_SCHEME_MBE:
796:       root = 0;
797:       for (j=0;j<i%matctx->subc->n;j++) root += matctx->subc->subsize[j];
798:       PetscCall(PetscMPIIntCast(k,&len));
799:       PetscCallMPI(MPI_Bcast(dHi,len,MPIU_SCALAR,root,matctx->subc->dupparent));
800:       break;
801:     case PEP_REFINE_SCHEME_SCHUR:
802:       break;
803:     }
804:   }
805:   PetscFunctionReturn(PETSC_SUCCESS);
806: }

808: static PetscErrorCode PEPNRefForwardSubstitution(PEP pep,PetscInt k,PetscScalar *S,PetscInt lds,PetscScalar *H,PetscInt ldh,PetscScalar *fH,BV dV,PetscScalar *dVS,PetscInt *rds,PetscScalar *dH,PetscInt lddh,KSP ksp,PEP_REFINE_EXPLICIT *matctx)
809: {
810:   PetscInt            i,nmat=pep->nmat,lda=nmat*k;
811:   PetscScalar         *fh,*Rh,*DfH;
812:   PetscReal           norm;
813:   BV                  W;
814:   Vec                 Rv,t,dvi;
815:   PEP_REFINE_MATSHELL *ctx;
816:   Mat                 M,*At;
817:   PetscBool           flg,lindep;

819:   PetscFunctionBegin;
820:   PetscCall(PetscMalloc2(nmat*k*k,&DfH,k,&Rh));
821:   *rds = 0;
822:   PetscCall(BVCreateVec(pep->V,&Rv));
823:   switch (pep->scheme) {
824:   case PEP_REFINE_SCHEME_EXPLICIT:
825:     PetscCall(BVCreateVec(pep->V,&t));
826:     PetscCall(BVDuplicateResize(pep->V,PetscMax(k,nmat),&W));
827:     PetscCall(PetscMalloc1(nmat,&fh));
828:     break;
829:   case PEP_REFINE_SCHEME_MBE:
830:     if (matctx->subc) {
831:       PetscCall(BVCreateVec(pep->V,&t));
832:       PetscCall(BVDuplicateResize(pep->V,PetscMax(k,nmat),&W));
833:     } else {
834:       W = matctx->W;
835:       PetscCall(PetscObjectReference((PetscObject)W));
836:       t = matctx->t;
837:       PetscCall(PetscObjectReference((PetscObject)t));
838:     }
839:     PetscCall(BVScale(matctx->W,0.0));
840:     PetscCall(BVScale(matctx->Wt,0.0));
841:     PetscCall(BVScale(matctx->M2,0.0));
842:     PetscCall(BVScale(matctx->M3,0.0));
843:     PetscCall(PetscMalloc1(nmat,&fh));
844:     break;
845:   case PEP_REFINE_SCHEME_SCHUR:
846:     PetscCall(KSPGetOperators(ksp,&M,NULL));
847:     PetscCall(MatShellGetContext(M,&ctx));
848:     PetscCall(BVCreateVec(pep->V,&t));
849:     PetscCall(BVDuplicateResize(pep->V,PetscMax(k,nmat),&W));
850:     fh = ctx->fih;
851:     break;
852:   }
853:   PetscCall(PetscArrayzero(dVS,2*k*k));
854:   PetscCall(PetscArrayzero(DfH,lda*k));
855:   PetscCall(STGetTransform(pep->st,&flg));
856:   if (flg) {
857:     PetscCall(PetscMalloc1(pep->nmat,&At));
858:     for (i=0;i<pep->nmat;i++) PetscCall(STGetMatrixTransformed(pep->st,i,&At[i]));
859:   } else At = pep->A;

861:   /* Main loop for computing the i-th columns of dX and dS */
862:   for (i=0;i<k;i++) {
863:     /* Compute and update i-th column of the right hand side */
864:     PetscCall(PetscArrayzero(Rh,k));
865:     PetscCall(NRefRightSide(nmat,pep->pbc,At,k,pep->V,S,lds,i,H,ldh,fH,DfH,dH,dV,dVS,*rds,Rv,Rh,W,t));

867:     /* Update and solve system */
868:     PetscCall(BVGetColumn(dV,i,&dvi));
869:     PetscCall(NRefSysIter(i,pep,k,ksp,fH,S,lds,fh,H,ldh,Rv,Rh,pep->V,dvi,dH+i*k,matctx,W));
870:     /* Orthogonalize computed solution */
871:     PetscCall(BVOrthogonalizeVec(pep->V,dvi,dVS+i*2*k,&norm,&lindep));
872:     PetscCall(BVRestoreColumn(dV,i,&dvi));
873:     if (!lindep) {
874:       PetscCall(BVOrthogonalizeColumn(dV,i,dVS+k+i*2*k,&norm,&lindep));
875:       if (!lindep) {
876:         dVS[k+i+i*2*k] = norm;
877:         PetscCall(BVScaleColumn(dV,i,1.0/norm));
878:         (*rds)++;
879:       }
880:     }
881:   }
882:   PetscCall(BVSetActiveColumns(dV,0,*rds));
883:   PetscCall(VecDestroy(&t));
884:   PetscCall(VecDestroy(&Rv));
885:   PetscCall(BVDestroy(&W));
886:   if (flg) PetscCall(PetscFree(At));
887:   PetscCall(PetscFree2(DfH,Rh));
888:   if (pep->scheme!=PEP_REFINE_SCHEME_SCHUR) PetscCall(PetscFree(fh));
889:   PetscFunctionReturn(PETSC_SUCCESS);
890: }

892: static PetscErrorCode NRefOrthogStep(PEP pep,PetscInt k,PetscScalar *H,PetscInt ldh,PetscScalar *fH,PetscScalar *S,PetscInt lds)
893: {
894:   PetscInt       j,nmat=pep->nmat,deg=nmat-1,lda=nmat*k,ldg;
895:   PetscScalar    *G,*tau,sone=1.0,zero=0.0,*work;
896:   PetscBLASInt   lds_,k_,ldh_,ldg_,lda_;

898:   PetscFunctionBegin;
899:   PetscCall(PetscMalloc3(k,&tau,k,&work,deg*k*k,&G));
900:   PetscCall(PetscBLASIntCast(lds,&lds_));
901:   PetscCall(PetscBLASIntCast(lda,&lda_));
902:   PetscCall(PetscBLASIntCast(k,&k_));

904:   /* Form auxiliary matrix for the orthogonalization step */
905:   ldg = deg*k;
906:   PetscCall(PEPEvaluateBasisforMatrix(pep,nmat,k,H,ldh,fH));
907:   PetscCall(PetscBLASIntCast(ldg,&ldg_));
908:   PetscCall(PetscBLASIntCast(ldh,&ldh_));
909:   for (j=0;j<deg;j++) {
910:     PetscCallBLAS("BLASgemm",BLASgemm_("N","N",&k_,&k_,&k_,&sone,S,&lds_,fH+j*k,&lda_,&zero,G+j*k,&ldg_));
911:   }
912:   /* Orthogonalize and update S */
913:   PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
914:   PetscCallLAPACKInfo("LAPACKgeqrf",LAPACKgeqrf_(&ldg_,&k_,G,&ldg_,tau,work,&k_,&info));
915:   PetscCall(PetscFPTrapPop());
916:   PetscCallBLAS("BLAStrsm",BLAStrsm_("R","U","N","N",&k_,&k_,&sone,G,&ldg_,S,&lds_));

918:   /* Update H */
919:   PetscCallBLAS("BLAStrmm",BLAStrmm_("L","U","N","N",&k_,&k_,&sone,G,&ldg_,H,&ldh_));
920:   PetscCallBLAS("BLAStrsm",BLAStrsm_("R","U","N","N",&k_,&k_,&sone,G,&ldg_,H,&ldh_));
921:   PetscCall(PetscFree3(tau,work,G));
922:   PetscFunctionReturn(PETSC_SUCCESS);
923: }

925: static PetscErrorCode PEPNRefUpdateInvPair(PEP pep,PetscInt k,PetscScalar *H,PetscInt ldh,PetscScalar *fH,PetscScalar *dH,PetscScalar *S,PetscInt lds,BV dV,PetscScalar *dVS,PetscInt rds)
926: {
927:   PetscInt       i,j,nmat=pep->nmat,lda=nmat*k;
928:   PetscScalar    *tau,*array,*work;
929:   PetscBLASInt   lds_,k_,lda_,ldh_,kdrs_,k2_;
930:   Mat            M0;

932:   PetscFunctionBegin;
933:   PetscCall(PetscMalloc2(k,&tau,k,&work));
934:   PetscCall(PetscBLASIntCast(lds,&lds_));
935:   PetscCall(PetscBLASIntCast(lda,&lda_));
936:   PetscCall(PetscBLASIntCast(ldh,&ldh_));
937:   PetscCall(PetscBLASIntCast(k,&k_));
938:   PetscCall(PetscBLASIntCast(2*k,&k2_));
939:   PetscCall(PetscBLASIntCast((k+rds),&kdrs_));
940:   /* Update H */
941:   for (j=0;j<k;j++) {
942:     for (i=0;i<k;i++) H[i+j*ldh] -= dH[i+j*k];
943:   }
944:   /* Update V */
945:   for (j=0;j<k;j++) {
946:     for (i=0;i<k;i++) dVS[i+j*2*k] = -dVS[i+j*2*k]+S[i+j*lds];
947:     for (i=k;i<2*k;i++) dVS[i+j*2*k] = -dVS[i+j*2*k];
948:   }
949:   PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
950:   PetscCallLAPACKInfo("LAPACKgeqrf",LAPACKgeqrf_(&kdrs_,&k_,dVS,&k2_,tau,work,&k_,&info));
951:   /* Copy triangular matrix in S */
952:   for (j=0;j<k;j++) {
953:     for (i=0;i<=j;i++) S[i+j*lds] = dVS[i+j*2*k];
954:     for (i=j+1;i<k;i++) S[i+j*lds] = 0.0;
955:   }
956:   PetscCallLAPACKInfo("LAPACKorgqr",LAPACKorgqr_(&k2_,&k_,&k_,dVS,&k2_,tau,work,&k_,&info));
957:   PetscCall(PetscFPTrapPop());
958:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,NULL,&M0));
959:   PetscCall(MatDenseGetArrayWrite(M0,&array));
960:   for (j=0;j<k;j++) PetscCall(PetscArraycpy(array+j*k,dVS+j*2*k,k));
961:   PetscCall(MatDenseRestoreArrayWrite(M0,&array));
962:   PetscCall(BVMultInPlace(pep->V,M0,0,k));
963:   if (rds) {
964:     PetscCall(MatDenseGetArrayWrite(M0,&array));
965:     for (j=0;j<k;j++) PetscCall(PetscArraycpy(array+j*k,dVS+k+j*2*k,rds));
966:     PetscCall(MatDenseRestoreArrayWrite(M0,&array));
967:     PetscCall(BVMultInPlace(dV,M0,0,k));
968:     PetscCall(BVMult(pep->V,1.0,1.0,dV,NULL));
969:   }
970:   PetscCall(MatDestroy(&M0));
971:   PetscCall(NRefOrthogStep(pep,k,H,ldh,fH,S,lds));
972:   PetscCall(PetscFree2(tau,work));
973:   PetscFunctionReturn(PETSC_SUCCESS);
974: }

976: static PetscErrorCode PEPNRefSetUp(PEP pep,PetscInt k,PetscScalar *H,PetscInt ldh,PEP_REFINE_EXPLICIT *matctx,PetscBool ini)
977: {
978:   PEP_REFINE_MATSHELL *ctx;
979:   PetscScalar         t,*coef;
980:   const PetscScalar   *array;
981:   MatStructure        str;
982:   PetscInt            j,nmat=pep->nmat,n0,m0,n1,m1,n0_,m0_,n1_,m1_,N0,N1,p,*idx1,*idx2,count,si,i,l0;
983:   MPI_Comm            comm;
984:   PetscMPIInt         np;
985:   const PetscInt      *rgs0,*rgs1;
986:   Mat                 B,C,*E,*A,*At;
987:   IS                  is1,is2;
988:   Vec                 v;
989:   PetscBool           flg;
990:   Mat                 M,P;

992:   PetscFunctionBegin;
993:   PetscCall(PetscMalloc1(nmat,&coef));
994:   PetscCall(STGetTransform(pep->st,&flg));
995:   if (flg) {
996:     PetscCall(PetscMalloc1(pep->nmat,&At));
997:     for (i=0;i<pep->nmat;i++) PetscCall(STGetMatrixTransformed(pep->st,i,&At[i]));
998:   } else At = pep->A;
999:   switch (pep->scheme) {
1000:   case PEP_REFINE_SCHEME_EXPLICIT:
1001:     if (ini) {
1002:       if (matctx->subc) {
1003:         A = matctx->A;
1004:         PetscCall(PetscSubcommGetChild(matctx->subc,&comm));
1005:       } else {
1006:         A = At;
1007:         PetscCall(PetscObjectGetComm((PetscObject)pep,&comm));
1008:       }
1009:       E = matctx->E;
1010:       PetscCall(STGetMatStructure(pep->st,&str));
1011:       PetscCall(MatDuplicate(A[0],MAT_COPY_VALUES,&E[0]));
1012:       j = matctx->subc?matctx->subc->color:0;
1013:       PetscCall(PEPEvaluateBasis(pep,H[j+j*ldh],0,coef,NULL));
1014:       for (j=1;j<nmat;j++) PetscCall(MatAXPY(E[0],coef[j],A[j],str));
1015:       PetscCall(MatCreateDense(comm,PETSC_DECIDE,PETSC_DECIDE,k,k,NULL,&E[1]));
1016:       PetscCall(MatGetOwnershipRange(E[0],&n0,&m0));
1017:       PetscCall(MatGetOwnershipRange(E[1],&n1,&m1));
1018:       PetscCall(MatGetOwnershipRangeColumn(E[0],&n0_,&m0_));
1019:       PetscCall(MatGetOwnershipRangeColumn(E[1],&n1_,&m1_));
1020:       /* T12 and T21 are computed from V and V*, so,
1021:          they must have the same column and row ranges */
1022:       PetscCheck(m0_-n0_==m0-n0,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Inconsistent dimensions");
1023:       PetscCall(MatCreateDense(comm,m0-n0,m1_-n1_,PETSC_DECIDE,PETSC_DECIDE,NULL,&B));
1024:       PetscCall(MatCreateDense(comm,m1-n1,m0_-n0_,PETSC_DECIDE,PETSC_DECIDE,NULL,&C));
1025:       PetscCall(MatCreateTile(1.0,E[0],1.0,B,1.0,C,1.0,E[1],&M));
1026:       PetscCall(MatDestroy(&B));
1027:       PetscCall(MatDestroy(&C));
1028:       matctx->compM1 = PETSC_TRUE;
1029:       PetscCall(MatGetSize(E[0],NULL,&N0));
1030:       PetscCall(MatGetSize(E[1],NULL,&N1));
1031:       PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)M),&np));
1032:       PetscCall(MatGetOwnershipRanges(E[0],&rgs0));
1033:       PetscCall(MatGetOwnershipRanges(E[1],&rgs1));
1034:       PetscCall(PetscMalloc4(PetscMax(k,N1),&matctx->idxp,N0,&matctx->idxg,N0,&matctx->map0,N1,&matctx->map1));
1035:       /* Create column (and row) mapping */
1036:       for (p=0;p<np;p++) {
1037:         for (j=rgs0[p];j<rgs0[p+1];j++) matctx->map0[j] = j+rgs1[p];
1038:         for (j=rgs1[p];j<rgs1[p+1];j++) matctx->map1[j] = j+rgs0[p+1];
1039:       }
1040:       PetscCall(MatCreateVecs(M,NULL,&matctx->tN));
1041:       PetscCall(MatCreateVecs(matctx->E[1],NULL,&matctx->t1));
1042:       PetscCall(VecDuplicate(matctx->tN,&matctx->ttN));
1043:       if (matctx->subc) {
1044:         PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)pep),&np));
1045:         count = np*k;
1046:         PetscCall(PetscMalloc2(count,&idx1,count,&idx2));
1047:         PetscCall(VecCreateMPI(PetscObjectComm((PetscObject)pep),m1-n1,PETSC_DECIDE,&matctx->tp));
1048:         PetscCall(VecGetOwnershipRange(matctx->tp,&l0,NULL));
1049:         PetscCall(VecCreateMPI(PetscObjectComm((PetscObject)pep),k,PETSC_DECIDE,&matctx->tpg));
1050:         for (si=0;si<matctx->subc->n;si++) {
1051:           if (matctx->subc->color==si) {
1052:             j=0;
1053:             if (matctx->subc->color==si) {
1054:               for (p=0;p<np;p++) {
1055:                 for (i=n1;i<m1;i++) {
1056:                   idx1[j] = l0+i-n1;
1057:                   idx2[j++] =p*k+i;
1058:                 }
1059:               }
1060:             }
1061:             count = np*(m1-n1);
1062:           } else count =0;
1063:           PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)pep),count,idx1,PETSC_COPY_VALUES,&is1));
1064:           PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)pep),count,idx2,PETSC_COPY_VALUES,&is2));
1065:           PetscCall(VecScatterCreate(matctx->tp,is1,matctx->tpg,is2,&matctx->scatterp_id[si]));
1066:           PetscCall(ISDestroy(&is1));
1067:           PetscCall(ISDestroy(&is2));
1068:         }
1069:         PetscCall(PetscFree2(idx1,idx2));
1070:       } else PetscCall(VecScatterCreateToAll(matctx->t1,&matctx->scatterctx,&matctx->vseq));
1071:       P = M;
1072:     } else {
1073:       if (matctx->subc) {
1074:         /* Scatter vectors pep->V */
1075:         for (i=0;i<k;i++) {
1076:           PetscCall(BVGetColumn(pep->V,i,&v));
1077:           PetscCall(VecScatterBegin(matctx->scatter_sub,v,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
1078:           PetscCall(VecScatterEnd(matctx->scatter_sub,v,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
1079:           PetscCall(BVRestoreColumn(pep->V,i,&v));
1080:           PetscCall(VecGetArrayRead(matctx->tg,&array));
1081:           PetscCall(VecPlaceArray(matctx->t,(const PetscScalar*)array));
1082:           PetscCall(BVInsertVec(matctx->V,i,matctx->t));
1083:           PetscCall(VecResetArray(matctx->t));
1084:           PetscCall(VecRestoreArrayRead(matctx->tg,&array));
1085:         }
1086:       }
1087:     }
1088:     break;
1089:   case PEP_REFINE_SCHEME_MBE:
1090:     if (ini) {
1091:       if (matctx->subc) {
1092:         A = matctx->A;
1093:         PetscCall(PetscSubcommGetChild(matctx->subc,&comm));
1094:       } else {
1095:         matctx->V = pep->V;
1096:         A = At;
1097:         PetscCall(PetscObjectGetComm((PetscObject)pep,&comm));
1098:         PetscCall(MatCreateVecs(pep->A[0],&matctx->t,NULL));
1099:       }
1100:       PetscCall(STGetMatStructure(pep->st,&str));
1101:       PetscCall(MatDuplicate(A[0],MAT_COPY_VALUES,&matctx->M1));
1102:       j = matctx->subc?matctx->subc->color:0;
1103:       PetscCall(PEPEvaluateBasis(pep,H[j+j*ldh],0,coef,NULL));
1104:       for (j=1;j<nmat;j++) PetscCall(MatAXPY(matctx->M1,coef[j],A[j],str));
1105:       PetscCall(BVDuplicateResize(matctx->V,PetscMax(k,pep->nmat),&matctx->W));
1106:       PetscCall(BVDuplicateResize(matctx->V,k,&matctx->M2));
1107:       PetscCall(BVDuplicate(matctx->M2,&matctx->M3));
1108:       PetscCall(BVDuplicate(matctx->M2,&matctx->Wt));
1109:       PetscCall(PetscMalloc5(k*k,&matctx->M4,k*k,&matctx->w,k*k,&matctx->wt,k,&matctx->d,k,&matctx->dt));
1110:       matctx->compM1 = PETSC_TRUE;
1111:       M = matctx->M1;
1112:       P = M;
1113:     }
1114:     break;
1115:   case PEP_REFINE_SCHEME_SCHUR:
1116:     if (ini) {
1117:       PetscCall(PetscObjectGetComm((PetscObject)pep,&comm));
1118:       PetscCall(MatGetSize(At[0],&m0,&n0));
1119:       PetscCall(PetscMalloc1(1,&ctx));
1120:       PetscCall(STGetMatStructure(pep->st,&str));
1121:       /* Create a shell matrix to solve the linear system */
1122:       ctx->V = pep->V;
1123:       ctx->k = k; ctx->nmat = nmat;
1124:       PetscCall(PetscMalloc5(nmat,&ctx->A,k*k,&ctx->M4,k,&ctx->pM4,2*k*k,&ctx->work,nmat,&ctx->fih));
1125:       for (i=0;i<nmat;i++) ctx->A[i] = At[i];
1126:       PetscCall(PetscArrayzero(ctx->M4,k*k));
1127:       PetscCall(MatCreateShell(comm,PETSC_DECIDE,PETSC_DECIDE,m0,n0,ctx,&M));
1128:       PetscCall(MatShellSetOperation(M,MATOP_MULT,(PetscErrorCodeFn*)MatMult_FS));
1129:       PetscCall(BVDuplicateResize(ctx->V,PetscMax(k,pep->nmat),&ctx->W));
1130:       PetscCall(BVDuplicateResize(ctx->V,k,&ctx->M2));
1131:       PetscCall(BVDuplicate(ctx->M2,&ctx->M3));
1132:       PetscCall(BVCreateVec(pep->V,&ctx->t));
1133:       PetscCall(MatDuplicate(At[0],MAT_COPY_VALUES,&ctx->M1));
1134:       PetscCall(PEPEvaluateBasis(pep,H[0],0,coef,NULL));
1135:       for (j=1;j<nmat;j++) PetscCall(MatAXPY(ctx->M1,coef[j],At[j],str));
1136:       PetscCall(MatDuplicate(At[0],MAT_COPY_VALUES,&P));
1137:       /* Compute a precond matrix for the system */
1138:       t = H[0];
1139:       PetscCall(PEPEvaluateBasis(pep,t,0,coef,NULL));
1140:       for (j=1;j<nmat;j++) PetscCall(MatAXPY(P,coef[j],At[j],str));
1141:       ctx->compM1 = PETSC_TRUE;
1142:     }
1143:     break;
1144:   }
1145:   if (ini) {
1146:     PetscCall(PEPRefineGetKSP(pep,&pep->refineksp));
1147:     PetscCall(KSPSetErrorIfNotConverged(pep->refineksp,PETSC_TRUE));
1148:     PetscCall(PEP_KSPSetOperators(pep->refineksp,M,P));
1149:     PetscCall(KSPSetFromOptions(pep->refineksp));
1150:   }

1152:   if (!ini && matctx && matctx->subc) {
1153:      /* Scatter vectors pep->V */
1154:     for (i=0;i<k;i++) {
1155:       PetscCall(BVGetColumn(pep->V,i,&v));
1156:       PetscCall(VecScatterBegin(matctx->scatter_sub,v,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
1157:       PetscCall(VecScatterEnd(matctx->scatter_sub,v,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
1158:       PetscCall(BVRestoreColumn(pep->V,i,&v));
1159:       PetscCall(VecGetArrayRead(matctx->tg,&array));
1160:       PetscCall(VecPlaceArray(matctx->t,(const PetscScalar*)array));
1161:       PetscCall(BVInsertVec(matctx->V,i,matctx->t));
1162:       PetscCall(VecResetArray(matctx->t));
1163:       PetscCall(VecRestoreArrayRead(matctx->tg,&array));
1164:     }
1165:    }
1166:   PetscCall(PetscFree(coef));
1167:   if (flg) PetscCall(PetscFree(At));
1168:   PetscFunctionReturn(PETSC_SUCCESS);
1169: }

1171: static PetscErrorCode NRefSubcommSetup(PEP pep,PetscInt k,PEP_REFINE_EXPLICIT *matctx,PetscInt nsubc)
1172: {
1173:   PetscInt          i,si,j,m0,n0,nloc0,nloc_sub,*idx1,*idx2;
1174:   IS                is1,is2;
1175:   BVType            type;
1176:   Vec               v;
1177:   const PetscScalar *array;
1178:   Mat               *A;
1179:   PetscBool         flg;
1180:   MPI_Comm          contpar,child;

1182:   PetscFunctionBegin;
1183:   PetscCall(STGetTransform(pep->st,&flg));
1184:   if (flg) {
1185:     PetscCall(PetscMalloc1(pep->nmat,&A));
1186:     for (i=0;i<pep->nmat;i++) PetscCall(STGetMatrixTransformed(pep->st,i,&A[i]));
1187:   } else A = pep->A;
1188:   PetscCall(PetscSubcommGetChild(matctx->subc,&child));
1189:   PetscCall(PetscSubcommGetContiguousParent(matctx->subc,&contpar));

1191:   /* Duplicate pep matrices */
1192:   PetscCall(PetscMalloc3(pep->nmat,&matctx->A,nsubc,&matctx->scatter_id,nsubc,&matctx->scatterp_id));
1193:   for (i=0;i<pep->nmat;i++) PetscCall(MatCreateRedundantMatrix(A[i],0,child,MAT_INITIAL_MATRIX,&matctx->A[i]));

1195:   /* Create Scatter */
1196:   PetscCall(MatCreateVecs(matctx->A[0],&matctx->t,NULL));
1197:   PetscCall(MatGetLocalSize(matctx->A[0],&nloc_sub,NULL));
1198:   PetscCall(VecCreateMPI(contpar,nloc_sub,PETSC_DECIDE,&matctx->tg));
1199:   PetscCall(BVGetColumn(pep->V,0,&v));
1200:   PetscCall(VecGetOwnershipRange(v,&n0,&m0));
1201:   nloc0 = m0-n0;
1202:   PetscCall(PetscMalloc2(matctx->subc->n*nloc0,&idx1,matctx->subc->n*nloc0,&idx2));
1203:   j = 0;
1204:   for (si=0;si<matctx->subc->n;si++) {
1205:     for (i=n0;i<m0;i++) {
1206:       idx1[j]   = i;
1207:       idx2[j++] = i+pep->n*si;
1208:     }
1209:   }
1210:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)pep),matctx->subc->n*nloc0,idx1,PETSC_COPY_VALUES,&is1));
1211:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)pep),matctx->subc->n*nloc0,idx2,PETSC_COPY_VALUES,&is2));
1212:   PetscCall(VecScatterCreate(v,is1,matctx->tg,is2,&matctx->scatter_sub));
1213:   PetscCall(ISDestroy(&is1));
1214:   PetscCall(ISDestroy(&is2));
1215:   for (si=0;si<matctx->subc->n;si++) {
1216:     j=0;
1217:     for (i=n0;i<m0;i++) {
1218:       idx1[j] = i;
1219:       idx2[j++] = i+pep->n*si;
1220:     }
1221:     PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)pep),nloc0,idx1,PETSC_COPY_VALUES,&is1));
1222:     PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)pep),nloc0,idx2,PETSC_COPY_VALUES,&is2));
1223:     PetscCall(VecScatterCreate(v,is1,matctx->tg,is2,&matctx->scatter_id[si]));
1224:     PetscCall(ISDestroy(&is1));
1225:     PetscCall(ISDestroy(&is2));
1226:   }
1227:   PetscCall(BVRestoreColumn(pep->V,0,&v));
1228:   PetscCall(PetscFree2(idx1,idx2));

1230:   /* Duplicate pep->V vecs */
1231:   PetscCall(BVGetType(pep->V,&type));
1232:   PetscCall(BVCreate(child,&matctx->V));
1233:   PetscCall(BVSetType(matctx->V,type));
1234:   PetscCall(BVSetSizesFromVec(matctx->V,matctx->t,k));
1235:   if (pep->scheme==PEP_REFINE_SCHEME_EXPLICIT) PetscCall(BVDuplicateResize(matctx->V,PetscMax(k,pep->nmat),&matctx->W));
1236:   for (i=0;i<k;i++) {
1237:     PetscCall(BVGetColumn(pep->V,i,&v));
1238:     PetscCall(VecScatterBegin(matctx->scatter_sub,v,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
1239:     PetscCall(VecScatterEnd(matctx->scatter_sub,v,matctx->tg,INSERT_VALUES,SCATTER_FORWARD));
1240:     PetscCall(BVRestoreColumn(pep->V,i,&v));
1241:     PetscCall(VecGetArrayRead(matctx->tg,&array));
1242:     PetscCall(VecPlaceArray(matctx->t,(const PetscScalar*)array));
1243:     PetscCall(BVInsertVec(matctx->V,i,matctx->t));
1244:     PetscCall(VecResetArray(matctx->t));
1245:     PetscCall(VecRestoreArrayRead(matctx->tg,&array));
1246:   }

1248:   PetscCall(VecDuplicate(matctx->t,&matctx->Rv));
1249:   PetscCall(VecDuplicate(matctx->t,&matctx->Vi));
1250:   if (flg) PetscCall(PetscFree(A));
1251:   PetscFunctionReturn(PETSC_SUCCESS);
1252: }

1254: static PetscErrorCode NRefSubcommDestroy(PEP pep,PEP_REFINE_EXPLICIT *matctx)
1255: {
1256:   PetscInt       i;

1258:   PetscFunctionBegin;
1259:   PetscCall(VecScatterDestroy(&matctx->scatter_sub));
1260:   for (i=0;i<matctx->subc->n;i++) PetscCall(VecScatterDestroy(&matctx->scatter_id[i]));
1261:   for (i=0;i<pep->nmat;i++) PetscCall(MatDestroy(&matctx->A[i]));
1262:   if (pep->scheme==PEP_REFINE_SCHEME_EXPLICIT) {
1263:     for (i=0;i<matctx->subc->n;i++) PetscCall(VecScatterDestroy(&matctx->scatterp_id[i]));
1264:     PetscCall(VecDestroy(&matctx->tp));
1265:     PetscCall(VecDestroy(&matctx->tpg));
1266:     PetscCall(BVDestroy(&matctx->W));
1267:   }
1268:   PetscCall(PetscFree3(matctx->A,matctx->scatter_id,matctx->scatterp_id));
1269:   PetscCall(BVDestroy(&matctx->V));
1270:   PetscCall(VecDestroy(&matctx->t));
1271:   PetscCall(VecDestroy(&matctx->tg));
1272:   PetscCall(VecDestroy(&matctx->Rv));
1273:   PetscCall(VecDestroy(&matctx->Vi));
1274:   PetscFunctionReturn(PETSC_SUCCESS);
1275: }

1277: PetscErrorCode PEPNewtonRefinement_TOAR(PEP pep,PetscScalar sigma,PetscInt *maxits,PetscReal *tol,PetscInt k,PetscScalar *S,PetscInt lds)
1278: {
1279:   PetscScalar         *H,*work,*dH,*fH,*dVS;
1280:   PetscInt            ldh,i,j,its=1,nmat=pep->nmat,nsubc=pep->npart,rds;
1281:   PetscBLASInt        k_,ld_,*p;
1282:   BV                  dV;
1283:   PetscBool           sinvert,flg;
1284:   PEP_REFINE_EXPLICIT *matctx=NULL;
1285:   Vec                 v;
1286:   Mat                 M,P;
1287:   PEP_REFINE_MATSHELL *ctx;

1289:   PetscFunctionBegin;
1290:   PetscCall(PetscLogEventBegin(PEP_Refine,pep,0,0,0));
1291:   PetscCheck(k<=pep->n,PetscObjectComm((PetscObject)pep),PETSC_ERR_SUP,"Multiple Refinement available only for invariant pairs of dimension smaller than n=%" PetscInt_FMT,pep->n);
1292:   /* the input tolerance is not being taken into account (by the moment) */
1293:   its = *maxits;
1294:   PetscCall(PetscMalloc3(k*k,&dH,nmat*k*k,&fH,k,&work));
1295:   PetscCall(DSGetLeadingDimension(pep->ds,&ldh));
1296:   PetscCall(PetscMalloc1(2*k*k,&dVS));
1297:   PetscCall(STGetTransform(pep->st,&flg));
1298:   if (!flg && pep->st && pep->ops->backtransform) { /* BackTransform */
1299:     PetscCall(PetscBLASIntCast(k,&k_));
1300:     PetscCall(PetscBLASIntCast(ldh,&ld_));
1301:     PetscCall(PetscObjectTypeCompare((PetscObject)pep->st,STSINVERT,&sinvert));
1302:     if (sinvert) {
1303:       PetscCall(DSGetArray(pep->ds,DS_MAT_A,&H));
1304:       PetscCall(PetscMalloc1(k,&p));
1305:       PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
1306:       PetscCallLAPACKInfo("LAPACKgetrf",LAPACKgetrf_(&k_,&k_,H,&ld_,p,&info));
1307:       PetscCallLAPACKInfo("LAPACKgetri",LAPACKgetri_(&k_,H,&ld_,p,work,&k_,&info));
1308:       PetscCall(PetscFPTrapPop());
1309:       PetscCall(DSRestoreArray(pep->ds,DS_MAT_A,&H));
1310:       pep->ops->backtransform = NULL;
1311:     }
1312:     if (sigma!=0.0) {
1313:       PetscCall(DSGetArray(pep->ds,DS_MAT_A,&H));
1314:       for (i=0;i<k;i++) H[i+ldh*i] += sigma;
1315:       PetscCall(DSRestoreArray(pep->ds,DS_MAT_A,&H));
1316:       pep->ops->backtransform = NULL;
1317:     }
1318:   }
1319:   if ((pep->scale==PEP_SCALE_BOTH || pep->scale==PEP_SCALE_SCALAR) && pep->sfactor!=1.0) {
1320:     PetscCall(DSGetArray(pep->ds,DS_MAT_A,&H));
1321:     for (j=0;j<k;j++) {
1322:       for (i=0;i<k;i++) H[i+j*ldh] *= pep->sfactor;
1323:     }
1324:     PetscCall(DSRestoreArray(pep->ds,DS_MAT_A,&H));
1325:     if (!flg) {
1326:       /* Restore original values */
1327:       for (i=0;i<pep->nmat;i++) {
1328:         pep->pbc[pep->nmat+i] *= pep->sfactor;
1329:         pep->pbc[2*pep->nmat+i] *= pep->sfactor*pep->sfactor;
1330:       }
1331:     }
1332:   }
1333:   if ((pep->scale==PEP_SCALE_DIAGONAL || pep->scale==PEP_SCALE_BOTH) && pep->Dr) {
1334:     for (i=0;i<k;i++) {
1335:       PetscCall(BVGetColumn(pep->V,i,&v));
1336:       PetscCall(VecPointwiseMult(v,v,pep->Dr));
1337:       PetscCall(BVRestoreColumn(pep->V,i,&v));
1338:     }
1339:   }
1340:   PetscCall(DSGetArray(pep->ds,DS_MAT_A,&H));

1342:   PetscCall(NRefOrthogStep(pep,k,H,ldh,fH,S,lds));
1343:   /* check if H is in Schur form */
1344:   for (i=0;i<k-1;i++) {
1345: #if !PetscDefined(USE_COMPLEX)
1346:     PetscCheck(H[i+1+i*ldh]==0.0,PetscObjectComm((PetscObject)pep),PETSC_ERR_SUP,"Iterative Refinement requires the complex Schur form of the projected matrix");
1347: #else
1348:     PetscCheck(H[i+1+i*ldh]==0.0,PetscObjectComm((PetscObject)pep),PETSC_ERR_SUP,"Iterative Refinement requires an upper triangular projected matrix");
1349: #endif
1350:   }
1351:   PetscCheck(nsubc<=k,PetscObjectComm((PetscObject)pep),PETSC_ERR_SUP,"Number of subcommunicators should not be larger than the invariant pair dimension");
1352:   PetscCall(BVSetActiveColumns(pep->V,0,k));
1353:   PetscCall(BVDuplicateResize(pep->V,k,&dV));
1354:   if (pep->scheme!=PEP_REFINE_SCHEME_SCHUR) {
1355:     PetscCall(PetscMalloc1(1,&matctx));
1356:     if (nsubc>1) { /* splitting in subcommunicators */
1357:       matctx->subc = pep->refinesubc;
1358:       PetscCall(NRefSubcommSetup(pep,k,matctx,nsubc));
1359:     } else matctx->subc=NULL;
1360:   }

1362:   /* Loop performing iterative refinements */
1363:   for (i=0;i<its;i++) {
1364:     /* Pre-compute the polynomial basis evaluated in H */
1365:     PetscCall(PEPEvaluateBasisforMatrix(pep,nmat,k,H,ldh,fH));
1366:     PetscCall(PEPNRefSetUp(pep,k,H,ldh,matctx,PetscNot(i)));
1367:     /* Solve the linear system */
1368:     PetscCall(PEPNRefForwardSubstitution(pep,k,S,lds,H,ldh,fH,dV,dVS,&rds,dH,k,pep->refineksp,matctx));
1369:     /* Update X (=V*S) and H, and orthogonalize [X;X*fH1;...;XfH(deg-1)] */
1370:     PetscCall(PEPNRefUpdateInvPair(pep,k,H,ldh,fH,dH,S,lds,dV,dVS,rds));
1371:   }
1372:   PetscCall(DSRestoreArray(pep->ds,DS_MAT_A,&H));
1373:   if (!flg && sinvert) PetscCall(PetscFree(p));
1374:   PetscCall(PetscFree3(dH,fH,work));
1375:   PetscCall(PetscFree(dVS));
1376:   PetscCall(BVDestroy(&dV));
1377:   switch (pep->scheme) {
1378:   case PEP_REFINE_SCHEME_EXPLICIT:
1379:     for (i=0;i<2;i++) PetscCall(MatDestroy(&matctx->E[i]));
1380:     PetscCall(PetscFree4(matctx->idxp,matctx->idxg,matctx->map0,matctx->map1));
1381:     PetscCall(VecDestroy(&matctx->tN));
1382:     PetscCall(VecDestroy(&matctx->ttN));
1383:     PetscCall(VecDestroy(&matctx->t1));
1384:     if (nsubc>1) PetscCall(NRefSubcommDestroy(pep,matctx));
1385:     else {
1386:       PetscCall(VecDestroy(&matctx->vseq));
1387:       PetscCall(VecScatterDestroy(&matctx->scatterctx));
1388:     }
1389:     PetscCall(PetscFree(matctx));
1390:     PetscCall(KSPGetOperators(pep->refineksp,&M,NULL));
1391:     PetscCall(MatDestroy(&M));
1392:     break;
1393:   case PEP_REFINE_SCHEME_MBE:
1394:     PetscCall(BVDestroy(&matctx->W));
1395:     PetscCall(BVDestroy(&matctx->Wt));
1396:     PetscCall(BVDestroy(&matctx->M2));
1397:     PetscCall(BVDestroy(&matctx->M3));
1398:     PetscCall(MatDestroy(&matctx->M1));
1399:     PetscCall(VecDestroy(&matctx->t));
1400:     PetscCall(PetscFree5(matctx->M4,matctx->w,matctx->wt,matctx->d,matctx->dt));
1401:     if (nsubc>1) PetscCall(NRefSubcommDestroy(pep,matctx));
1402:     PetscCall(PetscFree(matctx));
1403:     break;
1404:   case PEP_REFINE_SCHEME_SCHUR:
1405:     PetscCall(KSPGetOperators(pep->refineksp,&M,&P));
1406:     PetscCall(MatShellGetContext(M,&ctx));
1407:     PetscCall(PetscFree5(ctx->A,ctx->M4,ctx->pM4,ctx->work,ctx->fih));
1408:     PetscCall(MatDestroy(&ctx->M1));
1409:     PetscCall(BVDestroy(&ctx->M2));
1410:     PetscCall(BVDestroy(&ctx->M3));
1411:     PetscCall(BVDestroy(&ctx->W));
1412:     PetscCall(VecDestroy(&ctx->t));
1413:     PetscCall(PetscFree(ctx));
1414:     PetscCall(MatDestroy(&M));
1415:     PetscCall(MatDestroy(&P));
1416:     break;
1417:   }
1418:   PetscCall(PetscLogEventEnd(PEP_Refine,pep,0,0,0));
1419:   PetscFunctionReturn(PETSC_SUCCESS);
1420: }