void TrustRegionSolver3::calcSmallestEigVal(double &oEigVal, FloatArray &oEigVec, PetscSparseMtrx &K) {
PetscErrorCode ierr;
ST st;
double eig_rtol = 1.0e-3;
int max_iter = 10000;
int nroot = 1;
if ( !epsInit ) {
/*
* Create eigensolver context
*/
#ifdef __PARALLEL_MODE
MPI_Comm comm = engngModel->giveParallelComm();
#else
MPI_Comm comm = PETSC_COMM_SELF;
#endif
ierr = EPSCreate(comm, & eps);
checkPetscError(ierr);
epsInit = true;
}
ierr = EPSSetOperators( eps, * K.giveMtrx(), NULL );
checkPetscError(ierr);
ierr = EPSSetProblemType(eps, EPS_NHEP);
checkPetscError(ierr);
ierr = EPSGetST(eps, & st);
checkPetscError(ierr);
// ierr = STSetType(st, STCAYLEY);
// ierr = STSetType(st, STSINVERT);
ierr = STSetType(st, STSHIFT);
checkPetscError(ierr);
ierr = STSetMatStructure(st, SAME_NONZERO_PATTERN);
checkPetscError(ierr);
ierr = EPSSetTolerances(eps, ( PetscReal ) eig_rtol, max_iter);
checkPetscError(ierr);
ierr = EPSSetDimensions(eps, ( PetscInt ) nroot, PETSC_DECIDE, PETSC_DECIDE);
checkPetscError(ierr);
ierr = EPSSetWhichEigenpairs(eps, EPS_SMALLEST_REAL);
checkPetscError(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* Solve the eigensystem
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
EPSConvergedReason eig_reason;
int eig_nconv, eig_nite;
ierr = EPSSolve(eps);
checkPetscError(ierr);
ierr = EPSGetConvergedReason(eps, & eig_reason);
checkPetscError(ierr);
ierr = EPSGetIterationNumber(eps, & eig_nite);
checkPetscError(ierr);
// printf("SLEPcSolver::solve EPSConvergedReason: %d, number of iterations: %d\n", eig_reason, eig_nite);
ierr = EPSGetConverged(eps, & eig_nconv);
checkPetscError(ierr);
double smallest_eig_val = 1.0e20;
if ( eig_nconv > 0 ) {
// printf("SLEPcSolver :: solveYourselfAt: Convergence reached for RTOL=%20.15f\n", eig_rtol);
FloatArray eig_vals(nroot);
PetscScalar kr;
Vec Vr;
K.createVecGlobal(& Vr);
FloatArray Vr_loc;
for ( int i = 0; i < eig_nconv && i < nroot; i++ ) {
// PetscErrorCode EPSGetEigenpair(EPS eps,PetscInt i,PetscScalar *eigr,PetscScalar *eigi,Vec Vr,Vec Vi)
ierr = EPSGetEigenpair(eps, i, & kr, PETSC_NULL, Vr, PETSC_NULL);
checkPetscError(ierr);
//Store the eigenvalue
eig_vals(i) = kr;
if(kr < smallest_eig_val) {
smallest_eig_val = kr;
K.scatterG2L(Vr, Vr_loc);
oEigVec = Vr_loc;
}
}
ierr = VecDestroy(& Vr);
checkPetscError(ierr);
} else {
// OOFEM_ERROR("No converged eigenpairs.\n");
printf("Warning: No converged eigenpairs.\n");
smallest_eig_val = 1.0;
}
oEigVal = smallest_eig_val;
}
NM_Status
SLEPcSolver :: solve(SparseMtrx &a, SparseMtrx &b, FloatArray &_eigv, FloatMatrix &_r, double rtol, int nroot)
{
FILE *outStream;
PetscErrorCode ierr;
int size;
ST st;
outStream = domain->giveEngngModel()->giveOutputStream();
// first check whether Lhs is defined
if ( a->giveNumberOfRows() != a->giveNumberOfColumns() ||
b->giveNumberOfRows() != b->giveNumberOfRows() ||
a->giveNumberOfColumns() != b->giveNumberOfColumns() ) {
OOFEM_ERROR("matrices size mismatch");
}
A = dynamic_cast< PetscSparseMtrx * >(&a);
B = dynamic_cast< PetscSparseMtrx * >(&b);
if ( !A || !B ) {
OOFEM_ERROR("PetscSparseMtrx Expected");
}
size = engngModel->giveParallelContext( A->giveDomainIndex() )->giveNumberOfNaturalEqs(); // A->giveLeqs();
_r.resize(size, nroot);
_eigv.resize(nroot);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* Create the eigensolver and set various options
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
int nconv, nite;
EPSConvergedReason reason;
#ifdef TIME_REPORT
Timer timer;
timer.startTimer();
#endif
if ( !epsInit ) {
/*
* Create eigensolver context
*/
#ifdef __PARALLEL_MODE
MPI_Comm comm = engngModel->giveParallelComm();
#else
MPI_Comm comm = PETSC_COMM_SELF;
#endif
ierr = EPSCreate(comm, & eps);
CHKERRQ(ierr);
epsInit = true;
}
/*
* Set operators. In this case, it is a generalized eigenvalue problem
*/
ierr = EPSSetOperators( eps, * A->giveMtrx(), * B->giveMtrx() );
CHKERRQ(ierr);
ierr = EPSSetProblemType(eps, EPS_GHEP);
CHKERRQ(ierr);
ierr = EPSGetST(eps, & st);
CHKERRQ(ierr);
ierr = STSetType(st, STSINVERT);
CHKERRQ(ierr);
ierr = STSetMatStructure(st, SAME_NONZERO_PATTERN);
CHKERRQ(ierr);
ierr = EPSSetTolerances(eps, ( PetscReal ) rtol, PETSC_DECIDE);
CHKERRQ(ierr);
ierr = EPSSetDimensions(eps, ( PetscInt ) nroot, PETSC_DECIDE, PETSC_DECIDE);
CHKERRQ(ierr);
ierr = EPSSetWhichEigenpairs(eps, EPS_SMALLEST_MAGNITUDE);
CHKERRQ(ierr);
/*
* Set solver parameters at runtime
*/
ierr = EPSSetFromOptions(eps);
CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* Solve the eigensystem
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = EPSSolve(eps);
CHKERRQ(ierr);
ierr = EPSGetConvergedReason(eps, & reason);
CHKERRQ(ierr);
ierr = EPSGetIterationNumber(eps, & nite);
CHKERRQ(ierr);
OOFEM_LOG_INFO("SLEPcSolver::solve EPSConvergedReason: %d, number of iterations: %d\n", reason, nite);
ierr = EPSGetConverged(eps, & nconv);
CHKERRQ(ierr);
if ( nconv > 0 ) {
fprintf(outStream, "SLEPcSolver :: solveYourselfAt: Convergence reached for RTOL=%20.15f", rtol);
PetscScalar kr;
Vec Vr;
ierr = MatGetVecs(* B->giveMtrx(), PETSC_NULL, & Vr);
CHKERRQ(ierr);
FloatArray Vr_loc;
for ( int i = 0; i < nconv && i < nroot; i++ ) {
ierr = EPSGetEigenpair(eps, nconv - i - 1, & kr, PETSC_NULL, Vr, PETSC_NULL);
CHKERRQ(ierr);
//Store the eigenvalue
_eigv->at(i + 1) = kr;
//Store the eigenvector
A->scatterG2L(Vr, Vr_loc);
for ( int j = 0; j < size; j++ ) {
_r->at(j + 1, i + 1) = Vr_loc.at(j + 1);
}
}
ierr = VecDestroy(Vr);
CHKERRQ(ierr);
} else {
OOFEM_ERROR("No converged eigenpairs");
}
#ifdef TIME_REPORT
timer.stopTimer();
OOFEM_LOG_INFO( "SLEPcSolver info: user time consumed by solution: %.2fs\n", timer.getUtime() );
#endif
return NM_Success;
}
