Exemplo n.º 1
0
bool Test(const Teuchos::RefCountPtr<Epetra_RowMatrix>& Matrix, Teuchos::ParameterList& List)
{

  int NumVectors = 1;
  bool UseTranspose = false;

  Epetra_MultiVector LHS(Matrix->OperatorDomainMap(),NumVectors);
  Epetra_MultiVector RHS(Matrix->OperatorRangeMap(),NumVectors);
  Epetra_MultiVector LHSexact(Matrix->OperatorDomainMap(),NumVectors);

  LHS.PutScalar(0.0);
  LHSexact.Random();
  Matrix->Multiply(UseTranspose,LHSexact,RHS);

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

  Teuchos::RefCountPtr<T> Prec;
  
  Prec = Teuchos::rcp( new T(&*Matrix) );
  assert(Prec != Teuchos::null);

  IFPACK_CHK_ERR(Prec->SetParameters(List));
  IFPACK_CHK_ERR(Prec->Initialize());
  IFPACK_CHK_ERR(Prec->Compute());

  // create the AztecOO solver
  AztecOO AztecOOSolver(Problem);

  // specify solver
  AztecOOSolver.SetAztecOption(AZ_solver,AZ_gmres);
  AztecOOSolver.SetAztecOption(AZ_output,32);

  AztecOOSolver.SetPrecOperator(&*Prec);

  // solver. The solver should converge in one iteration,
  // or maximum two (numerical errors)
  AztecOOSolver.Iterate(1550,1e-8);

  cout << *Prec;
  
  vector<double> Norm(NumVectors);
  LHS.Update(1.0,LHSexact,-1.0);
  LHS.Norm2(&Norm[0]);
  for (int i = 0 ; i < NumVectors ; ++i) {
    cout << "Norm[" << i << "] = " << Norm[i] << endl;
    if (Norm[i] > 1e-3)
      return(false);
  }
  return(true);

}
Exemplo n.º 2
0
int main(int argc, char *argv[])
{

#ifdef HAVE_MPI
  MPI_Init(&argc,&argv);
  Epetra_MpiComm Comm( MPI_COMM_WORLD );
#else
  Epetra_SerialComm Comm;
#endif

  Teuchos::ParameterList GaleriList;

  // The problem is defined on a 2D grid, global size is nx * nx.
  int nx = 30; 
  GaleriList.set("n", nx * nx);
  GaleriList.set("nx", nx);
  GaleriList.set("ny", nx);
  Teuchos::RefCountPtr<Epetra_Map> Map = Teuchos::rcp( Galeri::CreateMap64("Linear", Comm, GaleriList) );
  Teuchos::RefCountPtr<Epetra_RowMatrix> A = Teuchos::rcp( Galeri::CreateCrsMatrix("Laplace2D", &*Map, GaleriList) );

  // =============================================================== //
  // B E G I N N I N G   O F   I F P A C K   C O N S T R U C T I O N //
  // =============================================================== //

  Teuchos::ParameterList List;

  // allocates an IFPACK factory. No data is associated 
  // to this object (only method Create()).
  Ifpack Factory;

  // create the preconditioner. For valid PrecType values,
  // please check the documentation
  string PrecType = "ILU"; // incomplete LU
  int OverlapLevel = 1; // must be >= 0. If Comm.NumProc() == 1,
                        // it is ignored.

  Teuchos::RefCountPtr<Ifpack_Preconditioner> Prec = Teuchos::rcp( Factory.Create(PrecType, &*A, OverlapLevel) );
  assert(Prec != Teuchos::null);

  // specify parameters for ILU
  List.set("fact: drop tolerance", 1e-9);
  List.set("fact: level-of-fill", 1);
  // the combine mode is on the following:
  // "Add", "Zero", "Insert", "InsertAdd", "Average", "AbsMax"
  // Their meaning is as defined in file Epetra_CombineMode.h   
  List.set("schwarz: combine mode", "Add");
  // sets the parameters
  IFPACK_CHK_ERR(Prec->SetParameters(List));

  // initialize the preconditioner. At this point the matrix must
  // have been FillComplete()'d, but actual values are ignored.
  IFPACK_CHK_ERR(Prec->Initialize());

  // Builds the preconditioners, by looking for the values of 
  // the matrix.
  IFPACK_CHK_ERR(Prec->Compute());

  // =================================================== //
  // E N D   O F   I F P A C K   C O N S T R U C T I O N //
  // =================================================== //

  // At this point, we need some additional objects
  // to define and solve the linear system.

  // defines LHS and RHS
  Epetra_Vector LHS(A->OperatorDomainMap());
  Epetra_Vector RHS(A->OperatorDomainMap());

  // solution is constant
  LHS.PutScalar(1.0);
  // now build corresponding RHS
  A->Apply(LHS,RHS);

  // now randomize the solution
  RHS.Random();

  // need an Epetra_LinearProblem to define AztecOO solver
  Epetra_LinearProblem Problem(&*A,&LHS,&RHS);

  // now we can allocate the AztecOO solver
  AztecOO Solver(Problem);

  // specify solver
  Solver.SetAztecOption(AZ_solver,AZ_gmres);
  Solver.SetAztecOption(AZ_output,32);

  // HERE WE SET THE IFPACK PRECONDITIONER
  Solver.SetPrecOperator(&*Prec);

  // .. and here we solve
  Solver.Iterate(1550,1e-8);

  cout << *Prec;

#ifdef HAVE_MPI
  MPI_Finalize() ; 
#endif

  return(EXIT_SUCCESS);
}
Exemplo n.º 3
0
int main(int argc, char *argv[])
{

  // initialize MPI and Epetra communicator
#ifdef HAVE_MPI
  MPI_Init(&argc,&argv);
  Epetra_MpiComm Comm( MPI_COMM_WORLD );
#else
  Epetra_SerialComm Comm;
#endif

  Teuchos::ParameterList GaleriList;

  // The problem is defined on a 2D grid, global size is nx * nx.
  int nx = 30; 
  GaleriList.set("nx", nx);
  GaleriList.set("ny", nx * Comm.NumProc());
  GaleriList.set("mx", 1);
  GaleriList.set("my", Comm.NumProc());
  Teuchos::RefCountPtr<Epetra_Map> Map = Teuchos::rcp( Galeri::CreateMap("Cartesian2D", Comm, GaleriList) );
  Teuchos::RefCountPtr<Epetra_RowMatrix> A = Teuchos::rcp( Galeri::CreateCrsMatrix("Laplace2D", &*Map, GaleriList) );

  // =============================================================== //
  // B E G I N N I N G   O F   I F P A C K   C O N S T R U C T I O N //
  // =============================================================== //

  Teuchos::ParameterList List;

  // allocates an IFPACK factory. No data is associated 
  // to this object (only method Create()).
  Ifpack Factory;

  // create the preconditioner. For valid PrecType values,
  // please check the documentation
  std::string PrecType = "Amesos";
  int OverlapLevel = 2; // must be >= 0. If Comm.NumProc() == 1,
                        // it is ignored.

  Teuchos::RefCountPtr<Ifpack_Preconditioner> Prec = Teuchos::rcp( Factory.Create(PrecType, &*A, OverlapLevel) );
  assert(Prec != Teuchos::null);

  // specify the Amesos solver to be used. 
  // If the selected solver is not available,
  // IFPACK will try to use Amesos' KLU (which is usually always
  // compiled). Amesos' serial solvers are:
  // "Amesos_Klu", "Amesos_Umfpack", "Amesos_Superlu"
  List.set("amesos: solver type", "Amesos_Klu");

  // sets the parameters
  IFPACK_CHK_ERR(Prec->SetParameters(List));

  // initialize the preconditioner. At this point the matrix must
  // have been FillComplete()'d, but actual values are ignored.
  // At this call, Amesos will perform the symbolic factorization.
  IFPACK_CHK_ERR(Prec->Initialize());

  // Builds the preconditioners, by looking for the values of 
  // the matrix. At this call, Amesos will perform the
  // numeric factorization.
  IFPACK_CHK_ERR(Prec->Compute());

  // =================================================== //
  // E N D   O F   I F P A C K   C O N S T R U C T I O N //
  // =================================================== //

  // At this point, we need some additional objects
  // to define and solve the linear system.

  // defines LHS and RHS
  Epetra_Vector LHS(A->OperatorDomainMap());
  Epetra_Vector RHS(A->OperatorDomainMap());

  // solution is constant
  LHS.PutScalar(1.0);
  // now build corresponding RHS
  A->Apply(LHS,RHS);

  // now randomize the solution
  RHS.Random();

  // need an Epetra_LinearProblem to define AztecOO solver
  Epetra_LinearProblem Problem(&*A,&LHS,&RHS);

  // now we can allocate the AztecOO solver
  AztecOO Solver(Problem);

  // specify solver
  Solver.SetAztecOption(AZ_solver,AZ_gmres);
  Solver.SetAztecOption(AZ_output,32);

  // HERE WE SET THE IFPACK PRECONDITIONER
  Solver.SetPrecOperator(&*Prec);

  // .. and here we solve
  // NOTE: with one process, the solver must converge in
  // one iteration.
  Solver.Iterate(1550,1e-8);

#ifdef HAVE_MPI
  MPI_Finalize() ; 
#endif

    return(EXIT_SUCCESS);
}
Exemplo n.º 4
0
int main(int argc, char *argv[])
{

  // initialize MPI and Epetra communicator
#ifdef HAVE_MPI
  MPI_Init(&argc,&argv);
  Epetra_MpiComm Comm( MPI_COMM_WORLD );
#else
  Epetra_SerialComm Comm;
#endif

  Teuchos::ParameterList GaleriList;

  // The problem is defined on a 2D grid, global size is nx * nx.
  int nx = 30; 
  GaleriList.set("nx", nx);
  GaleriList.set("ny", nx * Comm.NumProc());
  GaleriList.set("mx", 1);
  GaleriList.set("my", Comm.NumProc());
  Teuchos::RefCountPtr<Epetra_Map> Map = Teuchos::rcp( Galeri::CreateMap64("Cartesian2D", Comm, GaleriList) );
  Teuchos::RefCountPtr<Epetra_RowMatrix> A = Teuchos::rcp( Galeri::CreateCrsMatrix("Laplace2D", &*Map, GaleriList) );

  // =============================================================== //
  // B E G I N N I N G   O F   I F P A C K   C O N S T R U C T I O N //
  // =============================================================== //

  Teuchos::ParameterList List;

  // builds an Ifpack_AdditiveSchwarz. This is templated with
  // the local solvers, in this case Ifpack_ICT. Note that any
  // other Ifpack_Preconditioner-derived class can be used
  // instead of Ifpack_ICT.

  // In this example the overlap is zero. Use
  // Prec(A,OverlapLevel) for the general case.
  Ifpack_AdditiveSchwarz<Ifpack_ICT> Prec(&*A);

  // `1.0' means that the factorization should approximatively
  // keep the same number of nonzeros per row of the original matrix.
  List.set("fact: ict level-of-fill", 1.0);
  // no modifications on the diagonal
  List.set("fact: absolute threshold", 0.0);
  List.set("fact: relative threshold", 1.0);
  List.set("fact: relaxation value", 0.0);
  // matrix `laplace_2d_bc' is not symmetric because of the way
  // boundary conditions are imposed. We can filter the singletons,
  // (that is, Dirichlet nodes) and end up with a symmetric
  // matrix (as ICT requires).
  List.set("schwarz: filter singletons", true);

  // sets the parameters
  IFPACK_CHK_ERR(Prec.SetParameters(List));

  // initialize the preconditioner. At this point the matrix must
  // have been FillComplete()'d, but actual values are ignored.
  IFPACK_CHK_ERR(Prec.Initialize());

  // Builds the preconditioners, by looking for the values of 
  // the matrix. 
  IFPACK_CHK_ERR(Prec.Compute());

  // =================================================== //
  // E N D   O F   I F P A C K   C O N S T R U C T I O N //
  // =================================================== //

  // At this point, we need some additional objects
  // to define and solve the linear system.

  // defines LHS and RHS
  Epetra_Vector LHS(A->OperatorDomainMap());
  Epetra_Vector RHS(A->OperatorDomainMap());

  LHS.PutScalar(0.0);
  RHS.Random();

  // need an Epetra_LinearProblem to define AztecOO solver
  Epetra_LinearProblem Problem(&*A,&LHS,&RHS);

  // now we can allocate the AztecOO solver
  AztecOO Solver(Problem);

  // specify solver
  Solver.SetAztecOption(AZ_solver,AZ_cg_condnum);
  Solver.SetAztecOption(AZ_output,32);

  // HERE WE SET THE IFPACK PRECONDITIONER
  Solver.SetPrecOperator(&Prec);

  // .. and here we solve
  // NOTE: with one process, the solver must converge in
  // one iteration.
  Solver.Iterate(1550,1e-5);

  // Prints out some information about the preconditioner
  cout << Prec;

#ifdef HAVE_MPI
  MPI_Finalize(); 
#endif

  return (EXIT_SUCCESS);
}
int main(int argc, char *argv[])
{
  // initialize MPI and Epetra communicator
#ifdef HAVE_MPI
  MPI_Init(&argc,&argv);
  Epetra_MpiComm Comm( MPI_COMM_WORLD );
#else
  Epetra_SerialComm Comm;
#endif

  Teuchos::ParameterList GaleriList;

  // The problem is defined on a 2D grid, global size is nx * nx.
  int nx = 30; 
  GaleriList.set("nx", nx);
  GaleriList.set("ny", nx * Comm.NumProc());
  GaleriList.set("mx", 1);
  GaleriList.set("my", Comm.NumProc());
  Teuchos::RefCountPtr<Epetra_Map> Map = Teuchos::rcp( Galeri::CreateMap64("Cartesian2D", Comm, GaleriList) );
  Teuchos::RefCountPtr<Epetra_RowMatrix> A = Teuchos::rcp( Galeri::CreateCrsMatrix("Laplace2D", &*Map, GaleriList) );

  // =============================================================== //
  // B E G I N N I N G   O F   I F P A C K   C O N S T R U C T I O N //
  // =============================================================== //

  Teuchos::ParameterList List;

  // builds an Ifpack_AdditiveSchwarz. This is templated with
  // the local solvers, in this case Ifpack_BlockRelaxation.
  // Ifpack_BlockRelaxation requires as a templated a container
  // class. A container defines
  // how to store the diagonal blocks. Two choices are available:
  // Ifpack_DenseContainer (to store them as dense block,
  // than use LAPACK' factorization to apply the inverse of
  // each block), of Ifpack_SparseContainer (to store
  // the diagonal block as Epetra_CrsMatrix's). 
  // 
  // Here, we use Ifpack_SparseContainer, which in turn is
  // templated with the class to use to apply the inverse
  // of each block. For example, we can use Ifpack_Amesos.
 
  // We still have to decide the overlap among the processes,
  // and the overlap among the blocks. The two values
  // can be different. The overlap among the blocks is
  // considered only if block Jacobi is used.
  int OverlapProcs = 2;
  int OverlapBlocks = 0;

  // define the block below to use dense containers
#if 0
  Ifpack_AdditiveSchwarz<Ifpack_BlockRelaxation<Ifpack_DenseContainer> > Prec(A, OverlapProcs);
#else
  Ifpack_AdditiveSchwarz<Ifpack_BlockRelaxation<Ifpack_SparseContainer<Ifpack_Amesos> > > Prec(&*A, OverlapProcs);
#endif

  List.set("relaxation: type", "symmetric Gauss-Seidel");
  List.set("partitioner: overlap", OverlapBlocks);
#ifdef HAVE_IFPACK_METIS
  // use METIS to create the blocks. This requires --enable-ifpack-metis.
  // If METIS is not installed, the user may select "linear". 
  List.set("partitioner: type", "metis");
#else
  // or a simple greedy algorithm is METIS is not enabled
  List.set("partitioner: type", "greedy");
#endif
  // defines here the number of local blocks. If 1,
  // and only one process is used in the computation, then
  // the preconditioner must converge in one iteration. 
  List.set("partitioner: local parts", 4);

  // sets the parameters
  IFPACK_CHK_ERR(Prec.SetParameters(List));

  // initialize the preconditioner. 
  IFPACK_CHK_ERR(Prec.Initialize());

  // Builds the preconditioners.
  IFPACK_CHK_ERR(Prec.Compute());

  // =================================================== //
  // E N D   O F   I F P A C K   C O N S T R U C T I O N //
  // =================================================== //

  // At this point, we need some additional objects
  // to define and solve the linear system.

  // defines LHS and RHS
  Epetra_Vector LHS(A->OperatorDomainMap());
  Epetra_Vector RHS(A->OperatorDomainMap());

  LHS.PutScalar(0.0);
  RHS.Random();

  // need an Epetra_LinearProblem to define AztecOO solver
  Epetra_LinearProblem Problem(&*A,&LHS,&RHS);

  // now we can allocate the AztecOO solver
  AztecOO Solver(Problem);

  // specify solver
  Solver.SetAztecOption(AZ_solver,AZ_cg);
  Solver.SetAztecOption(AZ_output,32);

  // HERE WE SET THE IFPACK PRECONDITIONER
  Solver.SetPrecOperator(&Prec);

  // .. and here we solve
  // NOTE: with one process, the solver must converge in
  // one iteration.
  Solver.Iterate(1550,1e-5);

#ifdef HAVE_MPI
  MPI_Finalize() ; 
#endif

  return(EXIT_SUCCESS);
}