//=============================================================================
int Ifpack_CrsRiluk::Multiply(bool Trans, const Epetra_MultiVector& X,
Epetra_MultiVector& Y) const {
//
// This function finds X such that LDU Y = X or U(trans) D L(trans) Y = X for multiple RHS
//
// First generate X and Y as needed for this function
Teuchos::RefCountPtr<Epetra_MultiVector> X1;
Teuchos::RefCountPtr<Epetra_MultiVector> Y1;
EPETRA_CHK_ERR(GenerateXY(Trans, X, Y, &X1, &Y1));
#ifdef IFPACK_FLOPCOUNTERS
Epetra_Flops * counter = this->GetFlopCounter();
if (counter!=0) {
L_->SetFlopCounter(*counter);
Y1->SetFlopCounter(*counter);
U_->SetFlopCounter(*counter);
}
#endif
if (!Trans) {
EPETRA_CHK_ERR(U_->Multiply(Trans, *X1, *Y1)); //
EPETRA_CHK_ERR(Y1->Update(1.0, *X1, 1.0)); // Y1 = Y1 + X1 (account for implicit unit diagonal)
EPETRA_CHK_ERR(Y1->ReciprocalMultiply(1.0, *D_, *Y1, 0.0)); // y = D*y (D_ has inverse of diagonal)
Epetra_MultiVector Y1temp(*Y1); // Need a temp copy of Y1
EPETRA_CHK_ERR(L_->Multiply(Trans, Y1temp, *Y1));
EPETRA_CHK_ERR(Y1->Update(1.0, Y1temp, 1.0)); // (account for implicit unit diagonal)
if (IsOverlapped_) {EPETRA_CHK_ERR(Y.Export(*Y1,*L_->Exporter(), OverlapMode_));} // Export computed Y values if needed
}
else {
EPETRA_CHK_ERR(L_->Multiply(Trans, *X1, *Y1));
EPETRA_CHK_ERR(Y1->Update(1.0, *X1, 1.0)); // Y1 = Y1 + X1 (account for implicit unit diagonal)
EPETRA_CHK_ERR(Y1->ReciprocalMultiply(1.0, *D_, *Y1, 0.0)); // y = D*y (D_ has inverse of diagonal)
Epetra_MultiVector Y1temp(*Y1); // Need a temp copy of Y1
EPETRA_CHK_ERR(U_->Multiply(Trans, Y1temp, *Y1));
EPETRA_CHK_ERR(Y1->Update(1.0, Y1temp, 1.0)); // (account for implicit unit diagonal)
if (IsOverlapped_) {EPETRA_CHK_ERR(Y.Export(*Y1,*L_->Exporter(), OverlapMode_));}
}
return(0);
}
//=============================================================================
int Ifpack_CrsIct::Multiply(bool Trans, const Epetra_MultiVector& X,
Epetra_MultiVector& Y) const {
//
// This function finds X such that LDU Y = X or U(trans) D L(trans) Y = X for multiple RHS
//
if (X.NumVectors()!=Y.NumVectors()) EPETRA_CHK_ERR(-1); // Return error: X and Y not the same size
//bool Upper = true;
//bool Lower = false;
//bool UnitDiagonal = true;
Epetra_MultiVector * X1 = (Epetra_MultiVector *) &X;
Epetra_MultiVector * Y1 = (Epetra_MultiVector *) &Y;
U_->Multiply(false, *X1, *Y1);
Y1->Update(1.0, *X1, 1.0); // Y1 = Y1 + X1 (account for implicit unit diagonal)
Y1->ReciprocalMultiply(1.0, *D_, *Y1, 0.0); // y = D*y (D_ has inverse of diagonal)
Epetra_MultiVector Y1temp(*Y1); // Need a temp copy of Y1
U_->Multiply(true, Y1temp, *Y1);
Y1->Update(1.0, Y1temp, 1.0); // (account for implicit unit diagonal)
return(0);
}
