Actual source code: svdscalap.c
slepc-3.14.0 2020-09-30
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2020, 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 ScaLAPACK SVD solver
12: */
14: #include <slepc/private/svdimpl.h>
15: #include <slepc/private/slepcscalapack.h>
17: typedef struct {
18: Mat As; /* converted matrix */
19: } SVD_ScaLAPACK;
21: PetscErrorCode SVDSetUp_ScaLAPACK(SVD svd)
22: {
24: SVD_ScaLAPACK *ctx = (SVD_ScaLAPACK*)svd->data;
25: PetscInt M,N;
28: SVDMatGetSize(svd,&M,&N);
29: svd->ncv = N;
30: if (svd->mpd!=PETSC_DEFAULT) { PetscInfo(svd,"Warning: parameter mpd ignored\n"); }
31: if (svd->max_it==PETSC_DEFAULT) svd->max_it = 1;
32: svd->leftbasis = PETSC_TRUE;
33: SVDCheckUnsupported(svd,SVD_FEATURE_STOPPING);
34: SVDAllocateSolution(svd,0);
36: /* convert matrix */
37: MatDestroy(&ctx->As);
38: MatConvert(svd->OP,MATSCALAPACK,MAT_INITIAL_MATRIX,&ctx->As);
39: return(0);
40: }
42: PetscErrorCode SVDSolve_ScaLAPACK(SVD svd)
43: {
45: SVD_ScaLAPACK *ctx = (SVD_ScaLAPACK*)svd->data;
46: Mat A = ctx->As,Z,Q,QT,U,V;
47: Mat_ScaLAPACK *a = (Mat_ScaLAPACK*)A->data,*q,*z;
48: PetscScalar *work,minlwork;
49: PetscBLASInt info,lwork=-1,one=1;
50: #if defined(PETSC_USE_COMPLEX)
51: PetscBLASInt lrwork;
52: PetscReal *rwork,dummy;
53: #endif
56: MatDuplicate(A,MAT_DO_NOT_COPY_VALUES,&Z);
57: z = (Mat_ScaLAPACK*)Z->data;
58: MatCreate(PetscObjectComm((PetscObject)A),&QT);
59: MatSetSizes(QT,A->cmap->n,A->cmap->n,PETSC_DECIDE,PETSC_DECIDE);
60: MatSetType(QT,MATSCALAPACK);
61: MatSetUp(QT);
62: MatAssemblyBegin(QT,MAT_FINAL_ASSEMBLY);
63: MatAssemblyEnd(QT,MAT_FINAL_ASSEMBLY);
64: q = (Mat_ScaLAPACK*)QT->data;
66: #if !defined(PETSC_USE_COMPLEX)
67: /* allocate workspace */
68: PetscStackCallBLAS("SCALAPACKgesvd",SCALAPACKgesvd_("V","V",&a->M,&a->N,a->loc,&one,&one,a->desc,svd->sigma,z->loc,&one,&one,z->desc,q->loc,&one,&one,q->desc,&minlwork,&lwork,&info));
70: PetscBLASIntCast(minlwork,&lwork);
71: PetscMalloc1(lwork,&work);
72: /* call computational routine */
73: PetscStackCallBLAS("SCALAPACKgesvd",SCALAPACKgesvd_("V","V",&a->M,&a->N,a->loc,&one,&one,a->desc,svd->sigma,z->loc,&one,&one,z->desc,q->loc,&one,&one,q->desc,work,&lwork,&info));
75: PetscFree(work);
76: #else
77: /* allocate workspace */
78: PetscStackCallBLAS("SCALAPACKgesvd",SCALAPACKgesvd_("V","V",&a->M,&a->N,a->loc,&one,&one,a->desc,svd->sigma,z->loc,&one,&one,z->desc,q->loc,&one,&one,q->desc,&minlwork,&lwork,&dummy,&info));
80: PetscBLASIntCast(minlwork,&lwork);
81: lrwork = 1+4*PetscMax(a->M,a->N);
82: PetscMalloc2(lwork,&work,lrwork,&rwork);
83: /* call computational routine */
84: PetscStackCallBLAS("SCALAPACKgesvd",SCALAPACKgesvd_("V","V",&a->M,&a->N,a->loc,&one,&one,a->desc,svd->sigma,z->loc,&one,&one,z->desc,q->loc,&one,&one,q->desc,work,&lwork,rwork,&info));
86: PetscFree2(work,rwork);
87: #endif
89: BVGetMat(svd->U,&U);
90: MatConvert(Z,MATDENSE,MAT_REUSE_MATRIX,&U);
91: BVRestoreMat(svd->U,&U);
92: MatDestroy(&Z);
93: MatHermitianTranspose(QT,MAT_INITIAL_MATRIX,&Q);
94: MatDestroy(&QT);
95: BVGetMat(svd->V,&V);
96: MatConvert(Q,MATDENSE,MAT_REUSE_MATRIX,&V);
97: BVRestoreMat(svd->V,&V);
98: MatDestroy(&Q);
100: svd->nconv = svd->ncv;
101: svd->its = 1;
102: svd->reason = SVD_CONVERGED_TOL;
103: return(0);
104: }
106: PetscErrorCode SVDDestroy_ScaLAPACK(SVD svd)
107: {
111: PetscFree(svd->data);
112: return(0);
113: }
115: PetscErrorCode SVDReset_ScaLAPACK(SVD svd)
116: {
118: SVD_ScaLAPACK *ctx = (SVD_ScaLAPACK*)svd->data;
121: MatDestroy(&ctx->As);
122: return(0);
123: }
125: SLEPC_EXTERN PetscErrorCode SVDCreate_ScaLAPACK(SVD svd)
126: {
128: SVD_ScaLAPACK *ctx;
131: PetscNewLog(svd,&ctx);
132: svd->data = (void*)ctx;
134: svd->ops->solve = SVDSolve_ScaLAPACK;
135: svd->ops->setup = SVDSetUp_ScaLAPACK;
136: svd->ops->destroy = SVDDestroy_ScaLAPACK;
137: svd->ops->reset = SVDReset_ScaLAPACK;
138: return(0);
139: }