Esempi in C++ (Cpp) per RefCountPtr::ApplyInverse

Esempio n. 1

File: cxx_main.cpp Progetto: KineticTheory/Trilinos

// ======================================================================
bool TestContainer(std::string Type, const Teuchos::RefCountPtr<Epetra_RowMatrix>& A)
{
  using std::cout;
  using std::endl;

  int NumVectors = 3;
  int NumMyRows = A->NumMyRows();

  Epetra_MultiVector LHS_exact(A->RowMatrixRowMap(), NumVectors);
  Epetra_MultiVector LHS(A->RowMatrixRowMap(), NumVectors);
  Epetra_MultiVector RHS(A->RowMatrixRowMap(), NumVectors);
  LHS_exact.Random(); LHS.PutScalar(0.0);
  A->Multiply(false, LHS_exact, RHS);

  Epetra_LinearProblem Problem(&*A, &LHS, &RHS);

  if (verbose) {
    cout << "Container type = " << Type << endl;
    cout << "NumMyRows = " << NumMyRows << ", NumVectors = " << NumVectors << endl;
  }
  LHS.PutScalar(0.0);

  Teuchos::RefCountPtr<Ifpack_Container> Container;

  if (Type == "dense")
    Container = Teuchos::rcp( new Ifpack_DenseContainer(A->NumMyRows(), NumVectors) );
  else
    Container = Teuchos::rcp( new Ifpack_SparseContainer<Ifpack_Amesos>(A->NumMyRows(), NumVectors) );

  assert (Container != Teuchos::null);

  IFPACK_CHK_ERR(Container->Initialize());
  // set as ID all the local rows of A
  for (int i = 0 ; i < A->NumMyRows() ; ++i)
    Container->ID(i) = i;

  // extract submatrix (in this case, the entire matrix)
  // and complete setup
  IFPACK_CHK_ERR(Container->Compute(*A));

  // set the RHS and LHS
  for (int i = 0 ; i < A->NumMyRows() ; ++i)
    for (int j = 0 ; j < NumVectors ; ++j) {
      Container->RHS(i,j) = RHS[j][i];
      Container->LHS(i,j) = LHS[j][i];
    }

  // set parameters (empty for dense containers)
  Teuchos::ParameterList List;
  List.set("amesos: solver type", Type);
  IFPACK_CHK_ERR(Container->SetParameters(List));

  // solve the linear system
  IFPACK_CHK_ERR(Container->ApplyInverse());

  // get the computed solution, store it in LHS
  for (int i = 0 ; i < A->NumMyRows() ; ++i)
    for (int j = 0 ; j < NumVectors ; ++j) {
       LHS[j][i] = Container->LHS(i,j);
    }

  double residual = Galeri::ComputeNorm(&LHS, &LHS_exact);

  if (A->Comm().MyPID() == 0 && verbose) {
    cout << "||x_exact - x||_2 = " << residual << endl;
    cout << *Container;
  }

  bool passed = false;
  if (residual < 1e-5)
    passed = true;

  return(passed);
}