Actual source code: scalapack.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:    This file implements a wrapper to eigensolvers in ScaLAPACK.
 12: */

 14: #include <slepc/private/epsimpl.h>
 15: #include <slepc/private/slepcscalapack.h>

 17: typedef struct {
 18:   Mat As,Bs;        /* converted matrices */
 19: } EPS_ScaLAPACK;

 21: static PetscErrorCode EPSSetUp_ScaLAPACK(EPS eps)
 22: {
 23:   EPS_ScaLAPACK  *ctx = (EPS_ScaLAPACK*)eps->data;
 24:   Mat            A,B;
 25:   PetscInt       nmat;
 26:   PetscBool      isshift;
 27:   PetscScalar    shift;

 29:   PetscFunctionBegin;
 30:   EPSCheckHermitianDefinite(eps);
 31:   EPSCheckNotStructured(eps);
 32:   PetscCall(PetscObjectTypeCompare((PetscObject)eps->st,STSHIFT,&isshift));
 33:   PetscCheck(isshift,PetscObjectComm((PetscObject)eps),PETSC_ERR_SUP,"This solver does not support spectral transformations");
 34:   if (eps->nev==0) eps->nev = 1;
 35:   eps->ncv = eps->n;
 36:   if (eps->mpd!=PETSC_DETERMINE) PetscCall(PetscInfo(eps,"Warning: parameter mpd ignored\n"));
 37:   if (eps->max_it==PETSC_DETERMINE) eps->max_it = 1;
 38:   if (!eps->which) PetscCall(EPSSetWhichEigenpairs_Default(eps));
 39:   PetscCheck(eps->which!=EPS_ALL || eps->inta==eps->intb,PetscObjectComm((PetscObject)eps),PETSC_ERR_SUP,"This solver does not support interval computation");
 40:   EPSCheckUnsupported(eps,EPS_FEATURE_BALANCE | EPS_FEATURE_ARBITRARY | EPS_FEATURE_REGION);
 41:   EPSCheckIgnored(eps,EPS_FEATURE_EXTRACTION | EPS_FEATURE_CONVERGENCE | EPS_FEATURE_STOPPING);
 42:   PetscCall(EPSAllocateSolution(eps,0));

 44:   /* convert matrices */
 45:   PetscCall(MatDestroy(&ctx->As));
 46:   PetscCall(MatDestroy(&ctx->Bs));
 47:   PetscCall(STGetNumMatrices(eps->st,&nmat));
 48:   PetscCall(STGetMatrix(eps->st,0,&A));
 49:   PetscCall(MatConvert(A,MATSCALAPACK,MAT_INITIAL_MATRIX,&ctx->As));
 50:   if (nmat>1) {
 51:     PetscCall(STGetMatrix(eps->st,1,&B));
 52:     PetscCall(MatConvert(B,MATSCALAPACK,MAT_INITIAL_MATRIX,&ctx->Bs));
 53:   }
 54:   PetscCall(STGetShift(eps->st,&shift));
 55:   if (shift != 0.0) {
 56:     if (nmat>1) PetscCall(MatAXPY(ctx->As,-shift,ctx->Bs,SAME_NONZERO_PATTERN));
 57:     else PetscCall(MatShift(ctx->As,-shift));
 58:   }
 59:   PetscFunctionReturn(PETSC_SUCCESS);
 60: }

 62: static PetscErrorCode EPSSolve_ScaLAPACK(EPS eps)
 63: {
 64:   EPS_ScaLAPACK  *ctx = (EPS_ScaLAPACK*)eps->data;
 65:   Mat            A = ctx->As,B = ctx->Bs,Q,V;
 66:   Mat_ScaLAPACK  *a = (Mat_ScaLAPACK*)A->data,*b,*q;
 67:   PetscReal      rdummy=0.0,abstol=0.0,*gap=NULL,orfac=-1.0,*w = eps->errest;  /* used to store real eigenvalues */
 68:   PetscScalar    *work,minlwork[3];
 69:   PetscBLASInt   i,m,idummy=0,lwork=-1,liwork=-1,minliwork,*iwork,*ifail=NULL,*iclustr=NULL,one=1;
 70: #if PetscDefined(USE_COMPLEX)
 71:   PetscReal      *rwork,minlrwork[3];
 72:   PetscBLASInt   lrwork=-1;
 73: #endif

 75:   PetscFunctionBegin;
 76:   PetscCall(MatDuplicate(A,MAT_DO_NOT_COPY_VALUES,&Q));
 77:   PetscCall(PetscFPTrapPush(PETSC_FP_TRAP_OFF));
 78:   q = (Mat_ScaLAPACK*)Q->data;

 80:   if (B) {

 82:     b = (Mat_ScaLAPACK*)B->data;
 83:     PetscCall(PetscMalloc3(a->grid->nprow*a->grid->npcol,&gap,a->N,&ifail,2*a->grid->nprow*a->grid->npcol,&iclustr));
 84: #if !PetscDefined(USE_COMPLEX)
 85:     /* allocate workspace */
 86:     PetscCallScaLAPACKInfo("sygvx",SCALAPACKsygvx_(&one,"V","A","L",&a->N,a->loc,&one,&one,a->desc,b->loc,&one,&one,b->desc,&rdummy,&rdummy,&idummy,&idummy,&abstol,&m,&idummy,w,&orfac,q->loc,&one,&one,q->desc,minlwork,&lwork,&minliwork,&liwork,ifail,iclustr,gap,&info));
 87:     PetscCall(PetscBLASIntCast((PetscInt)minlwork[0],&lwork));
 88:     liwork = minliwork;
 89:     /* call computational routine */
 90:     PetscCall(PetscMalloc2(lwork,&work,liwork,&iwork));
 91:     PetscCallScaLAPACKInfo("sygvx",SCALAPACKsygvx_(&one,"V","A","L",&a->N,a->loc,&one,&one,a->desc,b->loc,&one,&one,b->desc,&rdummy,&rdummy,&idummy,&idummy,&abstol,&m,&idummy,w,&orfac,q->loc,&one,&one,q->desc,work,&lwork,iwork,&liwork,ifail,iclustr,gap,&info));
 92:     PetscCall(PetscFree2(work,iwork));
 93: #else
 94:     /* allocate workspace */
 95:     PetscCallScaLAPACKInfo("sygvx",SCALAPACKsygvx_(&one,"V","A","L",&a->N,a->loc,&one,&one,a->desc,b->loc,&one,&one,b->desc,&rdummy,&rdummy,&idummy,&idummy,&abstol,&m,&idummy,w,&orfac,q->loc,&one,&one,q->desc,minlwork,&lwork,minlrwork,&lrwork,&minliwork,&liwork,ifail,iclustr,gap,&info));
 96:     PetscCall(PetscBLASIntCast((PetscInt)PetscRealPart(minlwork[0]),&lwork));
 97:     PetscCall(PetscBLASIntCast((PetscInt)minlrwork[0],&lrwork));
 98:     lrwork += a->N*a->N;
 99:     liwork = minliwork;
100:     /* call computational routine */
101:     PetscCall(PetscMalloc3(lwork,&work,lrwork,&rwork,liwork,&iwork));
102:     PetscCallScaLAPACKInfo("sygvx",SCALAPACKsygvx_(&one,"V","A","L",&a->N,a->loc,&one,&one,a->desc,b->loc,&one,&one,b->desc,&rdummy,&rdummy,&idummy,&idummy,&abstol,&m,&idummy,w,&orfac,q->loc,&one,&one,q->desc,work,&lwork,rwork,&lrwork,iwork,&liwork,ifail,iclustr,gap,&info));
103:     PetscCall(PetscFree3(work,rwork,iwork));
104: #endif
105:     PetscCall(PetscFree3(gap,ifail,iclustr));

107:   } else {

109: #if !PetscDefined(USE_COMPLEX)
110:     /* allocate workspace */
111:     PetscCallScaLAPACKInfo("syev",SCALAPACKsyev_("V","L",&a->N,a->loc,&one,&one,a->desc,w,q->loc,&one,&one,q->desc,minlwork,&lwork,&info));
112:     PetscCall(PetscBLASIntCast((PetscInt)minlwork[0],&lwork));
113:     PetscCall(PetscMalloc1(lwork,&work));
114:     /* call computational routine */
115:     PetscCallScaLAPACKInfo("syev",SCALAPACKsyev_("V","L",&a->N,a->loc,&one,&one,a->desc,w,q->loc,&one,&one,q->desc,work,&lwork,&info));
116:     PetscCall(PetscFree(work));
117: #else
118:     /* allocate workspace */
119:     PetscCallScaLAPACKInfo("syev",SCALAPACKsyev_("V","L",&a->N,a->loc,&one,&one,a->desc,w,q->loc,&one,&one,q->desc,minlwork,&lwork,minlrwork,&lrwork,&info));
120:     PetscCall(PetscBLASIntCast((PetscInt)PetscRealPart(minlwork[0]),&lwork));
121:     lrwork = 4*a->N;  /* PetscCall(PetscBLASIntCast((PetscInt)minlrwork[0],&lrwork)); */
122:     PetscCall(PetscMalloc2(lwork,&work,lrwork,&rwork));
123:     /* call computational routine */
124:     PetscCallScaLAPACKInfo("syev",SCALAPACKsyev_("V","L",&a->N,a->loc,&one,&one,a->desc,w,q->loc,&one,&one,q->desc,work,&lwork,rwork,&lrwork,&info));
125:     PetscCall(PetscFree2(work,rwork));
126: #endif

128:   }
129:   PetscCall(PetscFPTrapPop());

131:   for (i=0;i<eps->ncv;i++) {
132:     eps->eigr[i]   = eps->errest[i];
133:     eps->errest[i] = PETSC_MACHINE_EPSILON;
134:   }

136:   PetscCall(BVGetMat(eps->V,&V));
137:   PetscCall(MatConvert(Q,MATDENSE,MAT_REUSE_MATRIX,&V));
138:   PetscCall(BVRestoreMat(eps->V,&V));
139:   PetscCall(MatDestroy(&Q));

141:   eps->nconv  = eps->ncv;
142:   eps->its    = 1;
143:   eps->reason = EPS_CONVERGED_TOL;
144:   PetscFunctionReturn(PETSC_SUCCESS);
145: }

147: static PetscErrorCode EPSDestroy_ScaLAPACK(EPS eps)
148: {
149:   PetscFunctionBegin;
150:   PetscCall(PetscFree(eps->data));
151:   PetscFunctionReturn(PETSC_SUCCESS);
152: }

154: static PetscErrorCode EPSReset_ScaLAPACK(EPS eps)
155: {
156:   EPS_ScaLAPACK  *ctx = (EPS_ScaLAPACK*)eps->data;

158:   PetscFunctionBegin;
159:   PetscCall(MatDestroy(&ctx->As));
160:   PetscCall(MatDestroy(&ctx->Bs));
161:   PetscFunctionReturn(PETSC_SUCCESS);
162: }

164: /*MC
165:    EPSSCALAPACK - EPSSCALAPACK = "scalapack" - A wrapper to ScaLAPACK
166:    eigensolvers {cite:p}`Bla97`.

168:    Notes:
169:    Only available for Hermitian problems, using subroutines `pdsyev` and
170:    `pdsygvx` and the analogs for other precisions.

172:    This is a direct eigensolver, that is, the full spectrum is computed.
173:    The computation involves redistributing the matrices from PETSc storage
174:    to ScaLAPACK distribution, and vice versa (this is done automatically
175:    by SLEPc). Alternatively, the user may create the problem matrices
176:    already with type `MATSCALAPACK`.

178:    Level: beginner

180: .seealso: [](ch:eps), `EPS`, `EPSType`, `EPSSetType()`
181: M*/
182: SLEPC_EXTERN PetscErrorCode EPSCreate_ScaLAPACK(EPS eps)
183: {
184:   EPS_ScaLAPACK  *ctx;

186:   PetscFunctionBegin;
187:   PetscCall(PetscNew(&ctx));
188:   eps->data = (void*)ctx;

190:   eps->categ = EPS_CATEGORY_OTHER;

192:   eps->ops->solve          = EPSSolve_ScaLAPACK;
193:   eps->ops->setup          = EPSSetUp_ScaLAPACK;
194:   eps->ops->setupsort      = EPSSetUpSort_Basic;
195:   eps->ops->destroy        = EPSDestroy_ScaLAPACK;
196:   eps->ops->reset          = EPSReset_ScaLAPACK;
197:   eps->ops->backtransform  = EPSBackTransform_Default;
198:   eps->ops->setdefaultst   = EPSSetDefaultST_NoFactor;
199:   PetscFunctionReturn(PETSC_SUCCESS);
200: }