/*
SLEPc singular value solver: "cross"
Method: Uses an Hermitian eigensolver for A^T*A
Last update: Jan 2007
*/
#include "src/svd/svdimpl.h" /*I "slepcsvd.h" I*/
#include "slepceps.h"
typedef struct {
EPS eps;
Mat mat;
Vec w,diag;
} SVD_CROSS;
#undef __FUNCT__
#define __FUNCT__ "ShellMatMult_CROSS"
PetscErrorCode ShellMatMult_CROSS(Mat B,Vec x, Vec y)
{
PetscErrorCode ierr;
SVD svd;
SVD_CROSS *cross;
PetscFunctionBegin;
ierr = MatShellGetContext(B,(void**)&svd);CHKERRQ(ierr);
cross = (SVD_CROSS *)svd->data;
ierr = SVDMatMult(svd,PETSC_FALSE,x,cross->w);CHKERRQ(ierr);
ierr = SVDMatMult(svd,PETSC_TRUE,cross->w,y);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "ShellMatGetDiagonal_CROSS"
PetscErrorCode ShellMatGetDiagonal_CROSS(Mat B,Vec d)
{
PetscErrorCode ierr;
SVD svd;
SVD_CROSS *cross;
PetscInt N,n,i,j,start,end,ncols;
PetscScalar *work1,*work2,*diag;
const PetscInt *cols;
const PetscScalar *vals;
PetscFunctionBegin;
ierr = MatShellGetContext(B,(void**)&svd);CHKERRQ(ierr);
cross = (SVD_CROSS *)svd->data;
if (!cross->diag) {
/* compute diagonal from rows and store in cross->diag */
ierr = VecDuplicate(d,&cross->diag);CHKERRQ(ierr);
ierr = SVDMatGetSize(svd,PETSC_NULL,&N);CHKERRQ(ierr);
ierr = SVDMatGetLocalSize(svd,PETSC_NULL,&n);CHKERRQ(ierr);
ierr = PetscMalloc(sizeof(PetscScalar)*N,&work1);CHKERRQ(ierr);
ierr = PetscMalloc(sizeof(PetscScalar)*N,&work2);CHKERRQ(ierr);
for (i=0;i<n;i++) work1[i] = work2[i] = 0.0;
if (svd->AT) {
ierr = MatGetOwnershipRange(svd->AT,&start,&end);CHKERRQ(ierr);
for (i=start;i<end;i++) {
ierr = MatGetRow(svd->AT,i,&ncols,PETSC_NULL,&vals);CHKERRQ(ierr);
for (j=0;j<ncols;j++)
work1[i] += vals[j]*vals[j];
ierr = MatRestoreRow(svd->AT,i,&ncols,PETSC_NULL,&vals);CHKERRQ(ierr);
}
} else {
ierr = MatGetOwnershipRange(svd->A,&start,&end);CHKERRQ(ierr);
for (i=start;i<end;i++) {
ierr = MatGetRow(svd->A,i,&ncols,&cols,&vals);CHKERRQ(ierr);
for (j=0;j<ncols;j++)
work1[cols[j]] += vals[j]*vals[j];
ierr = MatRestoreRow(svd->A,i,&ncols,&cols,&vals);CHKERRQ(ierr);
}
}
ierr = MPI_Allreduce(work1,work2,N,MPIU_SCALAR,MPI_SUM,svd->comm);CHKERRQ(ierr);
ierr = VecGetOwnershipRange(cross->diag,&start,&end);CHKERRQ(ierr);
ierr = VecGetArray(cross->diag,&diag);CHKERRQ(ierr);
for (i=start;i<end;i++)
diag[i-start] = work2[i];
ierr = VecRestoreArray(cross->diag,&diag);CHKERRQ(ierr);
ierr = PetscFree(work1);CHKERRQ(ierr);
ierr = PetscFree(work2);CHKERRQ(ierr);
}
ierr = VecCopy(cross->diag,d);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "SVDSetUp_CROSS"
PetscErrorCode SVDSetUp_CROSS(SVD svd)
{
PetscErrorCode ierr;
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
PetscInt n;
PetscFunctionBegin;
if (cross->mat) {
ierr = MatDestroy(cross->mat);CHKERRQ(ierr);
ierr = VecDestroy(cross->w);CHKERRQ(ierr);
}
if (cross->diag) {
ierr = VecDestroy(cross->diag);CHKERRQ(ierr);
}
ierr = SVDMatGetLocalSize(svd,PETSC_NULL,&n);CHKERRQ(ierr);
ierr = MatCreateShell(svd->comm,n,n,PETSC_DETERMINE,PETSC_DETERMINE,svd,&cross->mat);CHKERRQ(ierr);
ierr = MatShellSetOperation(cross->mat,MATOP_MULT,(void(*)(void))ShellMatMult_CROSS);CHKERRQ(ierr);
ierr = MatShellSetOperation(cross->mat,MATOP_GET_DIAGONAL,(void(*)(void))ShellMatGetDiagonal_CROSS);CHKERRQ(ierr);
ierr = SVDMatGetVecs(svd,PETSC_NULL,&cross->w);CHKERRQ(ierr);
ierr = EPSSetOperators(cross->eps,cross->mat,PETSC_NULL);CHKERRQ(ierr);
ierr = EPSSetProblemType(cross->eps,EPS_HEP);CHKERRQ(ierr);
ierr = EPSSetDimensions(cross->eps,svd->nsv,svd->ncv);CHKERRQ(ierr);
ierr = EPSSetTolerances(cross->eps,svd->tol,svd->max_it);CHKERRQ(ierr);
ierr = EPSSetUp(cross->eps);CHKERRQ(ierr);
ierr = EPSGetDimensions(cross->eps,PETSC_NULL,&svd->ncv);CHKERRQ(ierr);
ierr = EPSGetTolerances(cross->eps,&svd->tol,&svd->max_it);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "SVDSolve_CROSS"
PetscErrorCode SVDSolve_CROSS(SVD svd)
{
PetscErrorCode ierr;
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
int i;
PetscScalar sigma;
PetscFunctionBegin;
ierr = EPSSetWhichEigenpairs(cross->eps,svd->which == SVD_LARGEST ? EPS_LARGEST_REAL : EPS_SMALLEST_MAGNITUDE);CHKERRQ(ierr);
ierr = EPSSetInitialVector(cross->eps,svd->vec_initial);CHKERRQ(ierr);
ierr = EPSSolve(cross->eps);CHKERRQ(ierr);
ierr = EPSGetConverged(cross->eps,&svd->nconv);CHKERRQ(ierr);
ierr = EPSGetIterationNumber(cross->eps,&svd->its);CHKERRQ(ierr);
ierr = EPSGetConvergedReason(cross->eps,(EPSConvergedReason*)&svd->reason);CHKERRQ(ierr);
ierr = EPSGetOperationCounters(cross->eps,PETSC_NULL,&svd->dots,PETSC_NULL);CHKERRQ(ierr);
for (i=0;i<svd->nconv;i++) {
ierr = EPSGetEigenpair(cross->eps,i,&sigma,PETSC_NULL,svd->V[i],PETSC_NULL);CHKERRQ(ierr);
svd->sigma[i] = sqrt(PetscRealPart(sigma));
}
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "SVDMonitor_CROSS"
PetscErrorCode SVDMonitor_CROSS(EPS eps,int its,int nconv,PetscScalar *eigr,PetscScalar *eigi,PetscReal *errest,int nest,void *ctx)
{
int i;
SVD svd = (SVD)ctx;
PetscFunctionBegin;
for (i=0;i<nest;i++) {
svd->sigma[i] = sqrt(PetscRealPart(eigr[i]));
svd->errest[i] = errest[i];
}
SVDMonitor(svd,its,nconv,svd->sigma,svd->errest,nest);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "SVDSetFromOptions_CROSS"
PetscErrorCode SVDSetFromOptions_CROSS(SVD svd)
{
PetscErrorCode ierr;
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
PetscFunctionBegin;
ierr = EPSSetFromOptions(cross->eps);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
EXTERN_C_BEGIN
#undef __FUNCT__
#define __FUNCT__ "SVDCrossSetEPS_CROSS"
PetscErrorCode SVDCrossSetEPS_CROSS(SVD svd,EPS eps)
{
PetscErrorCode ierr;
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
PetscFunctionBegin;
PetscValidHeaderSpecific(eps,EPS_COOKIE,2);
PetscCheckSameComm(svd,1,eps,2);
ierr = PetscObjectReference((PetscObject)eps);CHKERRQ(ierr);
ierr = EPSDestroy(cross->eps);CHKERRQ(ierr);
cross->eps = eps;
svd->setupcalled = 0;
PetscFunctionReturn(0);
}
EXTERN_C_END
#undef __FUNCT__
#define __FUNCT__ "SVDCrossSetEPS"
/*@
SVDCrossSetEPS - Associates an eigensolver object (EPS) to the
singular value solver.
Collective on SVD
Input Parameters:
+ svd - singular value solver
- eps - the eigensolver object
Level: advanced
.seealso: SVDCrossGetEPS()
@*/
PetscErrorCode SVDCrossSetEPS(SVD svd,EPS eps)
{
PetscErrorCode ierr, (*f)(SVD,EPS eps);
PetscFunctionBegin;
PetscValidHeaderSpecific(svd,SVD_COOKIE,1);
ierr = PetscObjectQueryFunction((PetscObject)svd,"SVDCrossSetEPS_C",(void (**)())&f);CHKERRQ(ierr);
if (f) {
ierr = (*f)(svd,eps);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
EXTERN_C_BEGIN
#undef __FUNCT__
#define __FUNCT__ "SVDCrossGetEPS_CROSS"
PetscErrorCode SVDCrossGetEPS_CROSS(SVD svd,EPS *eps)
{
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
PetscFunctionBegin;
PetscValidPointer(eps,2);
*eps = cross->eps;
PetscFunctionReturn(0);
}
EXTERN_C_END
#undef __FUNCT__
#define __FUNCT__ "SVDCrossGetEPS"
/*@C
SVDCrossGetEPS - Retrieve the eigensolver object (EPS) associated
to the singular value solver.
Not Collective
Input Parameters:
. svd - singular value solver
Output Parameter:
. eps - the eigensolver object
Level: advanced
.seealso: SVDCrossSetEPS()
@*/
PetscErrorCode SVDCrossGetEPS(SVD svd,EPS *eps)
{
PetscErrorCode ierr, (*f)(SVD,EPS *eps);
PetscFunctionBegin;
PetscValidHeaderSpecific(svd,SVD_COOKIE,1);
ierr = PetscObjectQueryFunction((PetscObject)svd,"SVDCrossGetEPS_C",(void (**)())&f);CHKERRQ(ierr);
if (f) {
ierr = (*f)(svd,eps);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "SVDView_CROSS"
PetscErrorCode SVDView_CROSS(SVD svd,PetscViewer viewer)
{
PetscErrorCode ierr;
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
PetscFunctionBegin;
ierr = EPSView(cross->eps,viewer);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "SVDDestroy_CROSS"
PetscErrorCode SVDDestroy_CROSS(SVD svd)
{
PetscErrorCode ierr;
SVD_CROSS *cross = (SVD_CROSS *)svd->data;
PetscFunctionBegin;
ierr = EPSDestroy(cross->eps);CHKERRQ(ierr);
if (cross->mat) {
ierr = MatDestroy(cross->mat);CHKERRQ(ierr);
ierr = VecDestroy(cross->w);CHKERRQ(ierr);
}
if (cross->diag) {
ierr = VecDestroy(cross->diag);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
EXTERN_C_BEGIN
#undef __FUNCT__
#define __FUNCT__ "SVDCreate_CROSS"
PetscErrorCode SVDCreate_CROSS(SVD svd)
{
PetscErrorCode ierr;
SVD_CROSS *cross;
ST st;
PetscFunctionBegin;
ierr = PetscNew(SVD_CROSS,&cross);CHKERRQ(ierr);
PetscLogObjectMemory(svd,sizeof(SVD_CROSS));
svd->data = (void *)cross;
svd->ops->solve = SVDSolve_CROSS;
svd->ops->setup = SVDSetUp_CROSS;
svd->ops->setfromoptions = SVDSetFromOptions_CROSS;
svd->ops->destroy = SVDDestroy_CROSS;
svd->ops->view = SVDView_CROSS;
ierr = PetscObjectComposeFunctionDynamic((PetscObject)svd,"SVDCrossSetEPS_C","SVDCrossSetEPS_CROSS",SVDCrossSetEPS_CROSS);CHKERRQ(ierr);
ierr = PetscObjectComposeFunctionDynamic((PetscObject)svd,"SVDCrossGetEPS_C","SVDCrossGetEPS_CROSS",SVDCrossGetEPS_CROSS);CHKERRQ(ierr);
ierr = EPSCreate(svd->comm,&cross->eps);CHKERRQ(ierr);
ierr = EPSSetOptionsPrefix(cross->eps,svd->prefix);CHKERRQ(ierr);
ierr = EPSAppendOptionsPrefix(cross->eps,"svd_");CHKERRQ(ierr);
PetscLogObjectParent(svd,cross->eps);
ierr = EPSSetWhichEigenpairs(cross->eps,EPS_LARGEST_REAL);CHKERRQ(ierr);
ierr = EPSSetMonitor(cross->eps,SVDMonitor_CROSS,svd,PETSC_NULL);CHKERRQ(ierr);
ierr = EPSGetST(cross->eps,&st);CHKERRQ(ierr);
ierr = STSetMatMode(st,STMATMODE_SHELL);CHKERRQ(ierr);
cross->mat = PETSC_NULL;
cross->w = PETSC_NULL;
cross->diag = PETSC_NULL;
PetscFunctionReturn(0);
}
EXTERN_C_END