trilinos_solver.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2008 - 2018 by the deal.II authors
//
// This file is part of the deal.II library.
//
// The deal.II library is free software; you can use it, redistribute
// it, and/or modify it under the terms of the GNU Lesser General
// Public License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// The full text of the license can be found in the file LICENSE at
// the top level of the deal.II distribution.
//
// ---------------------------------------------------------------------

#ifndef dealii_trilinos_solver_h
#define dealii_trilinos_solver_h


#include <deal.II/base/config.h>

#ifdef DEAL_II_WITH_TRILINOS

#  include <deal.II/lac/exceptions.h>
#  include <deal.II/lac/solver_control.h>
#  include <deal.II/lac/vector.h>
#  include <deal.II/lac/la_parallel_vector.h>

#  include <memory>

#  include <Epetra_LinearProblem.h>
#  include <AztecOO.h>
#  include <Epetra_Operator.h>
#  include <Amesos.h>


DEAL_II_NAMESPACE_OPEN

namespace TrilinosWrappers
{
  // forward declarations
  class SparseMatrix;
  class PreconditionBase;


  class SolverBase
  {
  public:

    enum SolverName
    {
      cg,
      cgs,
      gmres,
      bicgstab,
      tfqmr
    } solver_name;

    struct AdditionalData
    {
      explicit
      AdditionalData (const bool         output_solver_details   = false,
                      const unsigned int gmres_restart_parameter = 30);

      const bool output_solver_details;

      const unsigned int gmres_restart_parameter;
    };

    SolverBase (SolverControl        &cn,
                const AdditionalData &data = AdditionalData());

    SolverBase (const enum SolverName  solver_name,
                SolverControl         &cn,
                const AdditionalData  &data = AdditionalData());

    virtual ~SolverBase () = default;

    void
    solve (const SparseMatrix     &A,
           MPI::Vector            &x,
           const MPI::Vector      &b,
           const PreconditionBase &preconditioner);

    void
    solve (const Epetra_Operator  &A,
           MPI::Vector            &x,
           const MPI::Vector      &b,
           const PreconditionBase &preconditioner);

    void
    solve (const Epetra_Operator  &A,
           MPI::Vector            &x,
           const MPI::Vector      &b,
           const Epetra_Operator  &preconditioner);

    void
    solve (const Epetra_Operator    &A,
           Epetra_MultiVector       &x,
           const Epetra_MultiVector &b,
           const PreconditionBase   &preconditioner);

    void
    solve (const Epetra_Operator    &A,
           Epetra_MultiVector       &x,
           const Epetra_MultiVector &b,
           const Epetra_Operator    &preconditioner);



    void
    solve (const SparseMatrix           &A,
           ::Vector<double>       &x,
           const ::Vector<double> &b,
           const PreconditionBase       &preconditioner);

    void
    solve (Epetra_Operator              &A,
           ::Vector<double>       &x,
           const ::Vector<double> &b,
           const PreconditionBase       &preconditioner);

    void
    solve (const SparseMatrix                                  &A,
           ::LinearAlgebra::distributed::Vector<double>       &x,
           const ::LinearAlgebra::distributed::Vector<double> &b,
           const PreconditionBase                              &preconditioner);

    void
    solve (Epetra_Operator                                     &A,
           ::LinearAlgebra::distributed::Vector<double>       &x,
           const ::LinearAlgebra::distributed::Vector<double> &b,
           const PreconditionBase                              &preconditioner);


    SolverControl &control() const;

    DeclException1 (ExcTrilinosError,
                    int,
                    << "An error with error number " << arg1
                    << " occurred while calling a Trilinos function");

  protected:

    SolverControl &solver_control;

  private:

    template <typename Preconditioner>
    void do_solve(const Preconditioner &preconditioner);

    template <typename Preconditioner>
    void set_preconditioner (AztecOO              &solver,
                             const Preconditioner &preconditioner);

    std::unique_ptr<Epetra_LinearProblem> linear_problem;

    std::unique_ptr<AztecOO_StatusTest> status_test;

    AztecOO solver;

    const AdditionalData additional_data;
  };


  // provide a declaration for two explicit specializations
  template <>
  void
  SolverBase::set_preconditioner(AztecOO                &solver,
                                 const PreconditionBase &preconditioner);

  template <>
  void
  SolverBase::set_preconditioner(AztecOO               &solver,
                                 const Epetra_Operator &preconditioner);



  class SolverCG : public SolverBase
  {
  public:
    struct AdditionalData : public SolverBase::AdditionalData
    {
      explicit
      AdditionalData (const bool output_solver_details = false);
    };

    SolverCG (SolverControl        &cn,
              const AdditionalData &data = AdditionalData());

  protected:
    const AdditionalData additional_data;
  };



  class SolverCGS : public SolverBase
  {
  public:
    struct AdditionalData : public SolverBase::AdditionalData
    {
      explicit
      AdditionalData (const bool output_solver_details = false);
    };

    SolverCGS (SolverControl        &cn,
               const AdditionalData &data = AdditionalData());

  protected:
    const AdditionalData additional_data;
  };



  class SolverGMRES : public SolverBase
  {
  public:
    struct AdditionalData : public SolverBase::AdditionalData
    {
      explicit
      AdditionalData (const bool         output_solver_details = false,
                      const unsigned int restart_parameter = 30);
    };

    SolverGMRES (SolverControl        &cn,
                 const AdditionalData &data = AdditionalData());

  protected:
    const AdditionalData additional_data;
  };



  class SolverBicgstab : public SolverBase
  {
  public:
    struct AdditionalData : public SolverBase::AdditionalData
    {
      explicit
      AdditionalData (const bool output_solver_details = false);
    };

    SolverBicgstab (SolverControl        &cn,
                    const AdditionalData &data = AdditionalData());

  protected:
    const AdditionalData additional_data;
  };



  class SolverTFQMR : public SolverBase
  {
  public:
    struct AdditionalData : public SolverBase::AdditionalData
    {
      explicit
      AdditionalData (const bool output_solver_details = false);
    };

    SolverTFQMR (SolverControl        &cn,
                 const AdditionalData &data = AdditionalData());

  protected:
    const AdditionalData additional_data;
  };



  class SolverDirect
  {
  public:

    struct AdditionalData
    {
      explicit
      AdditionalData (const bool output_solver_details = false,
                      const std::string &solver_type = "Amesos_Klu");

      bool output_solver_details;

      std::string solver_type;
    };

    SolverDirect (SolverControl  &cn,
                  const AdditionalData &data = AdditionalData());

    virtual ~SolverDirect () = default;

    void initialize (const SparseMatrix &A);

    void solve (MPI::Vector &x, const MPI::Vector &b);

    void
    solve (::LinearAlgebra::distributed::Vector<double>       &x,
           const ::LinearAlgebra::distributed::Vector<double> &b);

    void
    solve (const SparseMatrix     &A,
           MPI::Vector            &x,
           const MPI::Vector      &b);

    void
    solve (const SparseMatrix           &A,
           ::Vector<double>       &x,
           const ::Vector<double> &b);

    void
    solve (const SparseMatrix                                  &A,
           ::LinearAlgebra::distributed::Vector<double>       &x,
           const ::LinearAlgebra::distributed::Vector<double> &b);

    SolverControl &control() const;

    DeclException1 (ExcTrilinosError,
                    int,
                    << "An error with error number " << arg1
                    << " occurred while calling a Trilinos function");

  private:
    void do_solve();

    SolverControl &solver_control;

    std::unique_ptr<Epetra_LinearProblem> linear_problem;

    std::unique_ptr<Amesos_BaseSolver> solver;

    const AdditionalData additional_data;
  };

}

DEAL_II_NAMESPACE_CLOSE

#endif // DEAL_II_WITH_TRILINOS

/*----------------------------   trilinos_solver.h     ---------------------------*/

#endif
/*----------------------------   trilinos_solver.h     ---------------------------*/