/*
This file implements a wrapper to the TRLAN package
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SLEPc - Scalable Library for Eigenvalue Problem Computations
Copyright (c) 2002-2010, Universidad Politecnica de Valencia, Spain
This file is part of SLEPc.
SLEPc is free software: you can redistribute it and/or modify it under the
terms of version 3 of the GNU Lesser General Public License as published by
the Free Software Foundation.
SLEPc is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
more details.
You should have received a copy of the GNU Lesser General Public License
along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
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*/
#include "src/eps/impls/external/trlan/trlanp.h"
PetscErrorCode EPSSolve_TRLAN(EPS);
/* Nasty global variable to access EPS data from TRLan_ */
static EPS globaleps;
#undef __FUNCT__
#define __FUNCT__ "EPSSetUp_TRLAN"
PetscErrorCode EPSSetUp_TRLAN(EPS eps)
{
PetscErrorCode ierr;
EPS_TRLAN *tr = (EPS_TRLAN *)eps->data;
PetscFunctionBegin;
if (eps->ncv) {
if (eps->ncv<eps->nev) SETERRQ(1,"The value of ncv must be at least nev");
}
else eps->ncv = eps->nev;
if (eps->mpd) PetscInfo(eps,"Warning: parameter mpd ignored\n");
if (!eps->max_it) eps->max_it = PetscMax(1000,eps->n);
if (!eps->ishermitian)
SETERRQ(PETSC_ERR_SUP,"Requested method is only available for Hermitian problems");
if (eps->isgeneralized)
SETERRQ(PETSC_ERR_SUP,"Requested method is not available for generalized problems");
if (!eps->which) eps->which = EPS_LARGEST_REAL;
if (eps->which!=EPS_LARGEST_REAL && eps->which!=EPS_SMALLEST_REAL)
SETERRQ(1,"Wrong value of eps->which");
tr->restart = 0;
tr->maxlan = PetscBLASIntCast(eps->nev+PetscMin(eps->nev,6));
if (tr->maxlan+1-eps->ncv<=0) { tr->lwork = PetscBLASIntCast(tr->maxlan*(tr->maxlan+10)); }
else { tr->lwork = PetscBLASIntCast(eps->nloc*(tr->maxlan+1-eps->ncv) + tr->maxlan*(tr->maxlan+10)); }
ierr = PetscMalloc(tr->lwork*sizeof(PetscReal),&tr->work);CHKERRQ(ierr);
if (eps->extraction) {
ierr = PetscInfo(eps,"Warning: extraction type ignored\n");CHKERRQ(ierr);
}
ierr = EPSAllocateSolution(eps);CHKERRQ(ierr);
/* dispatch solve method */
if (eps->leftvecs) SETERRQ(PETSC_ERR_SUP,"Left vectors not supported in this solver");
eps->ops->solve = EPSSolve_TRLAN;
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "MatMult_TRLAN"
static PetscBLASInt MatMult_TRLAN(PetscBLASInt *n,PetscBLASInt *m,PetscReal *xin,PetscBLASInt *ldx,PetscReal *yout,PetscBLASInt *ldy)
{
PetscErrorCode ierr;
Vec x,y;
PetscBLASInt i;
PetscFunctionBegin;
ierr = VecCreateMPIWithArray(((PetscObject)globaleps)->comm,*n,PETSC_DECIDE,PETSC_NULL,&x);CHKERRQ(ierr);
ierr = VecCreateMPIWithArray(((PetscObject)globaleps)->comm,*n,PETSC_DECIDE,PETSC_NULL,&y);CHKERRQ(ierr);
for (i=0;i<*m;i++) {
ierr = VecPlaceArray(x,(PetscScalar*)xin+i*(*ldx));CHKERRQ(ierr);
ierr = VecPlaceArray(y,(PetscScalar*)yout+i*(*ldy));CHKERRQ(ierr);
ierr = STApply(globaleps->OP,x,y);CHKERRQ(ierr);
ierr = IPOrthogonalize(globaleps->ip,0,PETSC_NULL,globaleps->nds,PETSC_NULL,globaleps->DS,y,PETSC_NULL,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr);
ierr = VecResetArray(x);CHKERRQ(ierr);
ierr = VecResetArray(y);CHKERRQ(ierr);
}
ierr = VecDestroy(x);CHKERRQ(ierr);
ierr = VecDestroy(y);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "EPSSolve_TRLAN"
PetscErrorCode EPSSolve_TRLAN(EPS eps)
{
PetscErrorCode ierr;
PetscInt i;
PetscBLASInt ipar[32], n, lohi, stat, ncv;
EPS_TRLAN *tr = (EPS_TRLAN *)eps->data;
PetscScalar *pV;
PetscFunctionBegin;
ncv = PetscBLASIntCast(eps->ncv);
n = PetscBLASIntCast(eps->nloc);
if (eps->which==EPS_LARGEST_REAL) lohi = 1;
else if (eps->which==EPS_SMALLEST_REAL) lohi = -1;
else SETERRQ(1,"Wrong value of eps->which");
globaleps = eps;
ipar[0] = 0; /* stat: error flag */
ipar[1] = lohi; /* smallest (lohi<0) or largest eigenvalues (lohi>0) */
ipar[2] = PetscBLASIntCast(eps->nev); /* number of desired eigenpairs */
ipar[3] = 0; /* number of eigenpairs already converged */
ipar[4] = tr->maxlan; /* maximum Lanczos basis size */
ipar[5] = tr->restart; /* restarting scheme */
ipar[6] = PetscBLASIntCast(eps->max_it); /* maximum number of MATVECs */
ipar[7] = PetscBLASIntCast(MPI_Comm_c2f(((PetscObject)eps)->comm)); /* communicator */
ipar[8] = 0; /* verboseness */
ipar[9] = 99; /* Fortran IO unit number used to write log messages */
ipar[10] = 1; /* use supplied starting vector */
ipar[11] = 0; /* checkpointing flag */
ipar[12] = 98; /* Fortran IO unit number used to write checkpoint files */
ipar[13] = 0; /* number of flops per matvec per PE (not used) */
tr->work[0] = eps->tol; /* relative tolerance on residual norms */
for (i=0;i<eps->ncv;i++) eps->eigr[i]=0.0;
ierr = EPSGetStartVector(eps,0,eps->V[0],PETSC_NULL);CHKERRQ(ierr);
ierr = VecGetArray(eps->V[0],&pV);CHKERRQ(ierr);
TRLan_ ( MatMult_TRLAN, ipar, &n, &ncv, eps->eigr, pV, &n, tr->work, &tr->lwork );
ierr = VecRestoreArray( eps->V[0], &pV );CHKERRQ(ierr);
stat = ipar[0];
eps->nconv = ipar[3];
eps->its = ipar[25];
eps->reason = EPS_CONVERGED_TOL;
if (stat!=0) { SETERRQ1(PETSC_ERR_LIB,"Error in TRLAN (code=%d)",stat);}
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "EPSDestroy_TRLAN"
PetscErrorCode EPSDestroy_TRLAN(EPS eps)
{
PetscErrorCode ierr;
EPS_TRLAN *tr = (EPS_TRLAN *)eps->data;
PetscFunctionBegin;
PetscValidHeaderSpecific(eps,EPS_COOKIE,1);
ierr = PetscFree(tr->work);CHKERRQ(ierr);
ierr = PetscFree(eps->data);CHKERRQ(ierr);
ierr = EPSFreeSolution(eps);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
EXTERN_C_BEGIN
#undef __FUNCT__
#define __FUNCT__ "EPSCreate_TRLAN"
PetscErrorCode EPSCreate_TRLAN(EPS eps)
{
PetscErrorCode ierr;
EPS_TRLAN *trlan;
PetscFunctionBegin;
ierr = PetscNew(EPS_TRLAN,&trlan);CHKERRQ(ierr);
PetscLogObjectMemory(eps,sizeof(EPS_TRLAN));
eps->data = (void *) trlan;
eps->ops->setup = EPSSetUp_TRLAN;
eps->ops->destroy = EPSDestroy_TRLAN;
eps->ops->backtransform = EPSBackTransform_Default;
eps->ops->computevectors = EPSComputeVectors_Default;
PetscFunctionReturn(0);
}
EXTERN_C_END