Actual source code: svdlapack.c
slepc-3.21.1 2024-04-26
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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:    This file implements a wrapper to the LAPACK SVD subroutines
     12: */

     14: #include <slepc/private/svdimpl.h>
     15: #include <slepcblaslapack.h>

     17: static PetscErrorCode SVDSetUp_LAPACK(SVD svd)
     18: {
     19:   PetscInt       M,N,P=0;

     21:   PetscFunctionBegin;
     22:   PetscCall(MatGetSize(svd->A,&M,&N));
     23:   if (!svd->isgeneralized) svd->ncv = N;
     24:   else {
     25:     PetscCall(MatGetSize(svd->OPb,&P,NULL));
     26:     svd->ncv = PetscMin(M,PetscMin(N,P));
     27:   }
     28:   if (svd->mpd!=PETSC_DEFAULT) PetscCall(PetscInfo(svd,"Warning: parameter mpd ignored\n"));
     29:   SVDCheckUnsupported(svd,SVD_FEATURE_STOPPING);
     30:   if (svd->max_it==PETSC_DEFAULT) svd->max_it = 1;
     31:   svd->leftbasis = PETSC_TRUE;
     32:   PetscCall(SVDAllocateSolution(svd,0));
     33:   PetscCall(DSAllocate(svd->ds,PetscMax(N,PetscMax(M,P))));
     34:   PetscFunctionReturn(PETSC_SUCCESS);
     35: }

     37: static PetscErrorCode SVDSolve_LAPACK(SVD svd)
     38: {
     39:   PetscInt          M,N,n,i,j,k,ld,lowu,lowv,highu,highv;
     40:   Mat               A,Ar,mat;
     41:   Vec               u,v;
     42:   PetscScalar       *pU,*pV,*pu,*pv,*w;

     44:   PetscFunctionBegin;
     45:   PetscCall(DSGetLeadingDimension(svd->ds,&ld));
     46:   PetscCall(MatCreateRedundantMatrix(svd->OP,0,PETSC_COMM_SELF,MAT_INITIAL_MATRIX,&Ar));
     47:   PetscCall(MatConvert(Ar,MATSEQDENSE,MAT_INITIAL_MATRIX,&mat));
     48:   PetscCall(MatDestroy(&Ar));
     49:   PetscCall(MatGetSize(mat,&M,&N));
     50:   PetscCall(DSSetDimensions(svd->ds,M,0,0));
     51:   PetscCall(DSSVDSetDimensions(svd->ds,N));
     52:   PetscCall(DSGetMat(svd->ds,DS_MAT_A,&A));
     53:   PetscCall(MatCopy(mat,A,SAME_NONZERO_PATTERN));
     54:   PetscCall(DSRestoreMat(svd->ds,DS_MAT_A,&A));
     55:   PetscCall(DSSetState(svd->ds,DS_STATE_RAW));

     57:   n = PetscMin(M,N);
     58:   PetscCall(PetscMalloc1(n,&w));
     59:   PetscCall(DSSolve(svd->ds,w,NULL));
     60:   PetscCall(DSSort(svd->ds,w,NULL,NULL,NULL,NULL));
     61:   PetscCall(DSSynchronize(svd->ds,w,NULL));

     63:   /* copy singular vectors */
     64:   PetscCall(DSGetArray(svd->ds,DS_MAT_U,&pU));
     65:   PetscCall(DSGetArray(svd->ds,DS_MAT_V,&pV));
     66:   for (i=0;i<n;i++) {
     67:     if (svd->which == SVD_SMALLEST) k = n - i - 1;
     68:     else k = i;
     69:     svd->sigma[k] = PetscRealPart(w[i]);
     70:     PetscCall(BVGetColumn(svd->U,k,&u));
     71:     PetscCall(BVGetColumn(svd->V,k,&v));
     72:     PetscCall(VecGetOwnershipRange(u,&lowu,&highu));
     73:     PetscCall(VecGetOwnershipRange(v,&lowv,&highv));
     74:     PetscCall(VecGetArray(u,&pu));
     75:     PetscCall(VecGetArray(v,&pv));
     76:     if (M>=N) {
     77:       for (j=lowu;j<highu;j++) pu[j-lowu] = pU[i*ld+j];
     78:       for (j=lowv;j<highv;j++) pv[j-lowv] = pV[i*ld+j];
     79:     } else {
     80:       for (j=lowu;j<highu;j++) pu[j-lowu] = pV[i*ld+j];
     81:       for (j=lowv;j<highv;j++) pv[j-lowv] = pU[i*ld+j];
     82:     }
     83:     PetscCall(VecRestoreArray(u,&pu));
     84:     PetscCall(VecRestoreArray(v,&pv));
     85:     PetscCall(BVRestoreColumn(svd->U,k,&u));
     86:     PetscCall(BVRestoreColumn(svd->V,k,&v));
     87:   }
     88:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_U,&pU));
     89:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_V,&pV));

     91:   svd->nconv  = n;
     92:   svd->its    = 1;
     93:   svd->reason = SVD_CONVERGED_TOL;

     95:   PetscCall(MatDestroy(&mat));
     96:   PetscCall(PetscFree(w));
     97:   PetscFunctionReturn(PETSC_SUCCESS);
     98: }

    100: static PetscErrorCode SVDSolve_LAPACK_GSVD(SVD svd)
    101: {
    102:   PetscInt          nsv,m,n,p,i,j,mlocal,plocal,ld,lowx,lowu,lowv,highx;
    103:   Mat               Ar,A,Ads,Br,B,Bds;
    104:   Vec               uv,x;
    105:   PetscScalar       *U,*V,*X,*px,*puv,*w;

    107:   PetscFunctionBegin;
    108:   PetscCall(DSGetLeadingDimension(svd->ds,&ld));
    109:   PetscCall(MatCreateRedundantMatrix(svd->OP,0,PETSC_COMM_SELF,MAT_INITIAL_MATRIX,&Ar));
    110:   PetscCall(MatConvert(Ar,MATSEQDENSE,MAT_INITIAL_MATRIX,&A));
    111:   PetscCall(MatDestroy(&Ar));
    112:   PetscCall(MatCreateRedundantMatrix(svd->OPb,0,PETSC_COMM_SELF,MAT_INITIAL_MATRIX,&Br));
    113:   PetscCall(MatConvert(Br,MATSEQDENSE,MAT_INITIAL_MATRIX,&B));
    114:   PetscCall(MatDestroy(&Br));
    115:   PetscCall(MatGetSize(A,&m,&n));
    116:   PetscCall(MatGetLocalSize(svd->OP,&mlocal,NULL));
    117:   PetscCall(MatGetLocalSize(svd->OPb,&plocal,NULL));
    118:   PetscCall(MatGetSize(B,&p,NULL));
    119:   PetscCall(DSSetDimensions(svd->ds,m,0,0));
    120:   PetscCall(DSGSVDSetDimensions(svd->ds,n,p));
    121:   PetscCall(DSGetMat(svd->ds,DS_MAT_A,&Ads));
    122:   PetscCall(MatCopy(A,Ads,SAME_NONZERO_PATTERN));
    123:   PetscCall(DSRestoreMat(svd->ds,DS_MAT_A,&Ads));
    124:   PetscCall(DSGetMat(svd->ds,DS_MAT_B,&Bds));
    125:   PetscCall(MatCopy(B,Bds,SAME_NONZERO_PATTERN));
    126:   PetscCall(DSRestoreMat(svd->ds,DS_MAT_B,&Bds));
    127:   PetscCall(DSSetState(svd->ds,DS_STATE_RAW));

    129:   nsv  = PetscMin(n,PetscMin(p,m));
    130:   PetscCall(PetscMalloc1(nsv,&w));
    131:   PetscCall(DSSolve(svd->ds,w,NULL));
    132:   PetscCall(DSSort(svd->ds,w,NULL,NULL,NULL,NULL));
    133:   PetscCall(DSSynchronize(svd->ds,w,NULL));
    134:   PetscCall(DSGetDimensions(svd->ds,NULL,NULL,NULL,&nsv));

    136:   /* copy singular vectors */
    137:   PetscCall(MatGetOwnershipRange(svd->OP,&lowu,NULL));
    138:   PetscCall(MatGetOwnershipRange(svd->OPb,&lowv,NULL));
    139:   PetscCall(DSGetArray(svd->ds,DS_MAT_X,&X));
    140:   PetscCall(DSGetArray(svd->ds,DS_MAT_U,&U));
    141:   PetscCall(DSGetArray(svd->ds,DS_MAT_V,&V));
    142:   for (j=0;j<nsv;j++) {
    143:     svd->sigma[j] = PetscRealPart(w[j]);
    144:     PetscCall(BVGetColumn(svd->V,j,&x));
    145:     PetscCall(VecGetOwnershipRange(x,&lowx,&highx));
    146:     PetscCall(VecGetArrayWrite(x,&px));
    147:     for (i=lowx;i<highx;i++) px[i-lowx] = X[i+j*ld];
    148:     PetscCall(VecRestoreArrayWrite(x,&px));
    149:     PetscCall(BVRestoreColumn(svd->V,j,&x));
    150:     PetscCall(BVGetColumn(svd->U,j,&uv));
    151:     PetscCall(VecGetArrayWrite(uv,&puv));
    152:     for (i=0;i<mlocal;i++) puv[i] = U[i+lowu+j*ld];
    153:     for (i=0;i<plocal;i++) puv[i+mlocal] = V[i+lowv+j*ld];
    154:     PetscCall(VecRestoreArrayWrite(uv,&puv));
    155:     PetscCall(BVRestoreColumn(svd->U,j,&uv));
    156:   }
    157:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_X,&X));
    158:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_U,&U));
    159:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_V,&V));

    161:   svd->nconv  = nsv;
    162:   svd->its    = 1;
    163:   svd->reason = SVD_CONVERGED_TOL;

    165:   PetscCall(MatDestroy(&A));
    166:   PetscCall(MatDestroy(&B));
    167:   PetscCall(PetscFree(w));
    168:   PetscFunctionReturn(PETSC_SUCCESS);
    169: }

    171: static PetscErrorCode SVDSolve_LAPACK_HSVD(SVD svd)
    172: {
    173:   PetscInt          M,N,n,i,j,k,ld,lowu,lowv,highu,highv;
    174:   Mat               A,Ar,mat,D;
    175:   Vec               u,v,vomega;
    176:   PetscScalar       *pU,*pV,*pu,*pv,*w;
    177:   PetscReal         *pD;

    179:   PetscFunctionBegin;
    180:   PetscCall(DSGetLeadingDimension(svd->ds,&ld));
    181:   PetscCall(MatCreateRedundantMatrix(svd->OP,0,PETSC_COMM_SELF,MAT_INITIAL_MATRIX,&Ar));
    182:   PetscCall(MatConvert(Ar,MATSEQDENSE,MAT_INITIAL_MATRIX,&mat));
    183:   PetscCall(MatDestroy(&Ar));
    184:   PetscCall(MatGetSize(mat,&M,&N));
    185:   PetscCall(DSSetDimensions(svd->ds,M,0,0));
    186:   PetscCall(DSHSVDSetDimensions(svd->ds,N));
    187:   PetscCall(DSGetMat(svd->ds,DS_MAT_A,&A));
    188:   PetscCall(MatCopy(mat,A,SAME_NONZERO_PATTERN));
    189:   PetscCall(DSRestoreMat(svd->ds,DS_MAT_A,&A));
    190:   PetscCall(DSGetMatAndColumn(svd->ds,DS_MAT_D,0,&D,&vomega));
    191:   PetscCall(VecCopy(svd->omega,vomega));
    192:   PetscCall(DSRestoreMatAndColumn(svd->ds,DS_MAT_D,0,&D,&vomega));
    193:   PetscCall(DSSetState(svd->ds,DS_STATE_RAW));

    195:   n = PetscMin(M,N);
    196:   PetscCall(PetscMalloc1(n,&w));
    197:   PetscCall(DSSolve(svd->ds,w,NULL));
    198:   PetscCall(DSSort(svd->ds,w,NULL,NULL,NULL,NULL));
    199:   PetscCall(DSSynchronize(svd->ds,w,NULL));

    201:   /* copy singular vectors */
    202:   PetscCall(DSGetArrayReal(svd->ds,DS_MAT_D,&pD));
    203:   PetscCall(DSGetArray(svd->ds,DS_MAT_U,&pU));
    204:   PetscCall(DSGetArray(svd->ds,DS_MAT_V,&pV));
    205:   for (i=0;i<n;i++) {
    206:     if (svd->which == SVD_SMALLEST) k = n - i - 1;
    207:     else k = i;
    208:     svd->sigma[k] = PetscRealPart(w[i]);
    209:     svd->sign[k]  = pD[i];
    210:     PetscCall(BVGetColumn(svd->U,k,&u));
    211:     PetscCall(BVGetColumn(svd->V,k,&v));
    212:     PetscCall(VecGetOwnershipRange(u,&lowu,&highu));
    213:     PetscCall(VecGetOwnershipRange(v,&lowv,&highv));
    214:     PetscCall(VecGetArray(u,&pu));
    215:     PetscCall(VecGetArray(v,&pv));
    216:     if (M>=N) {
    217:       for (j=lowu;j<highu;j++) pu[j-lowu] = pU[i*ld+j];
    218:       for (j=lowv;j<highv;j++) pv[j-lowv] = pV[i*ld+j];
    219:     } else {
    220:       for (j=lowu;j<highu;j++) pu[j-lowu] = pV[i*ld+j];
    221:       for (j=lowv;j<highv;j++) pv[j-lowv] = pU[i*ld+j];
    222:     }
    223:     PetscCall(VecRestoreArray(u,&pu));
    224:     PetscCall(VecRestoreArray(v,&pv));
    225:     PetscCall(BVRestoreColumn(svd->U,k,&u));
    226:     PetscCall(BVRestoreColumn(svd->V,k,&v));
    227:   }
    228:   PetscCall(DSRestoreArrayReal(svd->ds,DS_MAT_D,&pD));
    229:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_U,&pU));
    230:   PetscCall(DSRestoreArray(svd->ds,DS_MAT_V,&pV));

    232:   svd->nconv  = n;
    233:   svd->its    = 1;
    234:   svd->reason = SVD_CONVERGED_TOL;

    236:   PetscCall(MatDestroy(&mat));
    237:   PetscCall(PetscFree(w));
    238:   PetscFunctionReturn(PETSC_SUCCESS);
    239: }

    241: static PetscErrorCode SVDSetDSType_LAPACK(SVD svd)
    242: {
    243:   PetscFunctionBegin;
    244:   PetscCall(DSSetType(svd->ds,svd->OPb?DSGSVD:svd->omega?DSHSVD:DSSVD));
    245:   PetscFunctionReturn(PETSC_SUCCESS);
    246: }

    248: SLEPC_EXTERN PetscErrorCode SVDCreate_LAPACK(SVD svd)
    249: {
    250:   PetscFunctionBegin;
    251:   svd->ops->setup     = SVDSetUp_LAPACK;
    252:   svd->ops->solve     = SVDSolve_LAPACK;
    253:   svd->ops->solveg    = SVDSolve_LAPACK_GSVD;
    254:   svd->ops->solveh    = SVDSolve_LAPACK_HSVD;
    255:   svd->ops->setdstype = SVDSetDSType_LAPACK;
    256:   PetscFunctionReturn(PETSC_SUCCESS);
    257: }