//! Do the transpose or conjugate transpose solve.
void applyTranspose (const MV& X_in, MV& Y_in, const Teuchos::ETransp mode) const
{
typedef Teuchos::ScalarTraits<Scalar> ST;
using Teuchos::null;
TEUCHOS_TEST_FOR_EXCEPTION
(mode != Teuchos::TRANS && mode != Teuchos::CONJ_TRANS, std::logic_error,
"Tpetra::CrsMatrixSolveOp::applyTranspose: mode is neither TRANS nor "
"CONJ_TRANS. Should never get here! Please report this bug to the "
"Tpetra developers.");
const size_t numVectors = X_in.getNumVectors();
Teuchos::RCP<const Import<LocalOrdinal,GlobalOrdinal,Node> > importer =
matrix_->getGraph ()->getImporter ();
Teuchos::RCP<const Export<LocalOrdinal,GlobalOrdinal,Node> > exporter =
matrix_->getGraph ()->getExporter ();
Teuchos::RCP<const MV> X;
// it is okay if X and Y reference the same data, because we can
// perform a triangular solve in-situ. however, we require that
// column access to each is strided.
// set up import/export temporary multivectors
if (importer != null) {
if (importMV_ != null && importMV_->getNumVectors() != numVectors) {
importMV_ = null;
}
if (importMV_ == null) {
importMV_ = Teuchos::rcp( new MV(matrix_->getColMap(),numVectors) );
}
}
if (exporter != null) {
if (exportMV_ != null && exportMV_->getNumVectors() != numVectors) {
exportMV_ = null;
}
if (exportMV_ == null) {
exportMV_ = Teuchos::rcp( new MV(matrix_->getRowMap(),numVectors) );
}
}
// solve(TRANS): DomainMap -> RangeMap
// lclMatSolve_(TRANS): ColMap -> RowMap
// importer: DomainMap -> ColMap
// exporter: RowMap -> RangeMap
//
// solve = importer o lclMatSolve_ o exporter
// Domainmap -> ColMap -> RowMap -> RangeMap
//
// If we have a non-trivial importer, we must import elements that
// are permuted or are on other processes.
if (importer != null) {
importMV_->doImport(X_in,*importer,INSERT);
X = importMV_;
}
else if (X_in.isConstantStride() == false) {
// cannot handle non-constant stride right now
// generate a copy of X_in
X = Teuchos::rcp(new MV(X_in));
}
else {
// just temporary, so this non-owning RCP is okay
X = Teuchos::rcpFromRef (X_in);
}
// If we have a non-trivial exporter, we must export elements that
// are permuted or belong to other processes. We will compute
// solution into the to-be-exported MV; get a view.
if (exporter != null) {
matrix_->template localSolve<Scalar, Scalar> (*X, *exportMV_,
Teuchos::CONJ_TRANS);
// Make sure target is zero: necessary because we are adding
Y_in.putScalar(ST::zero());
Y_in.doExport(*importMV_, *importer, ADD);
}
// otherwise, solve into Y
else {
if (Y_in.isConstantStride() == false) {
// generate a strided copy of Y
MV Y(Y_in);
matrix_->template localSolve<Scalar, Scalar> (*X, Y, Teuchos::CONJ_TRANS);
Y_in = Y;
}
else {
matrix_->template localSolve<Scalar, Scalar> (*X, Y_in, Teuchos::CONJ_TRANS);
}
}
}
//! Do the non-transpose solve.
void applyNonTranspose (const MV& X_in, MV& Y_in) const
{
using Teuchos::NO_TRANS;
using Teuchos::null;
typedef Teuchos::ScalarTraits<Scalar> ST;
// Solve U X = Y or L X = Y
// X belongs to domain map, while Y belongs to range map
const size_t numVectors = X_in.getNumVectors();
Teuchos::RCP<const Import<LocalOrdinal,GlobalOrdinal,Node> > importer =
matrix_->getGraph ()->getImporter ();
Teuchos::RCP<const Export<LocalOrdinal,GlobalOrdinal,Node> > exporter =
matrix_->getGraph ()->getExporter ();
Teuchos::RCP<const MV> X;
// it is okay if X and Y reference the same data, because we can
// perform a triangular solve in-situ. however, we require that
// column access to each is strided.
// set up import/export temporary multivectors
if (importer != null) {
if (importMV_ != null && importMV_->getNumVectors () != numVectors) {
importMV_ = null;
}
if (importMV_ == null) {
importMV_ = Teuchos::rcp (new MV (matrix_->getColMap (), numVectors));
}
}
if (exporter != null) {
if (exportMV_ != null && exportMV_->getNumVectors () != numVectors) {
exportMV_ = null;
}
if (exportMV_ == null) {
exportMV_ = Teuchos::rcp (new MV (matrix_->getRowMap (), numVectors));
}
}
// solve(NO_TRANS): RangeMap -> DomainMap
// lclMatSolve_: RowMap -> ColMap
// importer: DomainMap -> ColMap
// exporter: RowMap -> RangeMap
//
// solve = reverse(exporter) o lclMatSolve_ o reverse(importer)
// RangeMap -> RowMap -> ColMap -> DomainMap
//
// If we have a non-trivial exporter, we must import elements that
// are permuted or are on other processors
if (exporter != null) {
exportMV_->doImport (X_in, *exporter, INSERT);
X = exportMV_;
}
else if (! X_in.isConstantStride ()) {
// cannot handle non-constant stride right now
// generate a copy of X_in
X = Teuchos::rcp (new MV (X_in));
}
else {
// just temporary, so this non-owning RCP is okay
X = Teuchos::rcpFromRef (X_in);
}
// If we have a non-trivial importer, we must export elements that
// are permuted or belong to other processes. We will compute
// solution into the to-be-exported MV.
if (importer != null) {
matrix_->template localSolve<Scalar, Scalar> (*X, *importMV_, NO_TRANS);
// Make sure target is zero: necessary because we are adding.
Y_in.putScalar (ST::zero ());
Y_in.doExport (*importMV_, *importer, ADD);
}
// otherwise, solve into Y
else {
// can't solve into non-strided multivector
if (! Y_in.isConstantStride ()) {
// generate a strided copy of Y
MV Y (Y_in);
matrix_->template localSolve<Scalar, Scalar> (*X, Y, NO_TRANS);
Tpetra::deep_copy (Y_in, Y);
}
else {
matrix_->template localSolve<Scalar, Scalar> (*X, Y_in, NO_TRANS);
}
}
}
