libdolfin-dev 2016.2.0-2 / usr / include / dolfin / la / PETScLUSolver.h

// Copyright (C) 2005-2011 Anders Logg
//
// This file is part of DOLFIN.
//
// DOLFIN is free software: you can 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 3 of the License, or
// (at your option) any later version.
//
// DOLFIN is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with DOLFIN. If not, see <http://www.gnu.org/licenses/>.
//
// Modified by Garth N. Wells, 2009-2010.
//
// First added:  2005
// Last changed: 2011-10-19

#ifndef __DOLFIN_PETSC_LU_SOLVER_H
#define __DOLFIN_PETSC_LU_SOLVER_H

#ifdef HAS_PETSC

#include <map>
#include <memory>
#include <string>
#include <petscksp.h>
#include <petscpc.h>
#include <dolfin/common/MPI.h>
#include "GenericLUSolver.h"
#include "PETScObject.h"

namespace dolfin
{
  /// Forward declarations
  class GenericLinearOperator;
  class GenericVector;
  class PETScLinearOperator;
  class PETScMatrix;
  class PETScVector;
  class PETScSNESSolver;

  /// This class implements the direct solution (LU factorization) for
  /// linear systems of the form Ax = b. It is a wrapper for the LU
  /// solver of PETSc.

  class PETScLUSolver : public GenericLUSolver, public PETScObject
  {
  public:

    /// Constructor
    PETScLUSolver(MPI_Comm comm, std::string method="default");

    /// Constructor
    PETScLUSolver(std::string method="default");

    /// Constructor
    PETScLUSolver(MPI_Comm comm,
                  std::shared_ptr<const PETScMatrix> A,
                  std::string method="default");

    /// Constructor
    PETScLUSolver(std::shared_ptr<const PETScMatrix> A,
                  std::string method="default");

    /// Destructor
    ~PETScLUSolver();

    /// Set operator (matrix)
    void set_operator(std::shared_ptr<const GenericLinearOperator> A);

    /// Set operator (matrix)
    void set_operator(std::shared_ptr<const PETScMatrix> A);

    /// Get operator (matrix)
    const GenericLinearOperator& get_operator() const;

    /// Solve linear system Ax = b
    std::size_t solve(GenericVector& x, const GenericVector& b);

    /// Solve linear system Ax = b
    std::size_t solve(GenericVector& x, const GenericVector& b,
                      bool transpose);

    /// Solve linear system Ax = b
    std::size_t solve(const GenericLinearOperator& A, GenericVector& x,
                      const GenericVector& b);

    /// Solve linear system Ax = b
    std::size_t solve(const PETScMatrix& A, PETScVector& x,
                      const PETScVector& b);

    /// Solve linear system A^Tx = b
    std::size_t solve_transpose(GenericVector& x, const GenericVector& b);

    /// Solve linear system A^Tx = b
    std::size_t solve_transpose(const GenericLinearOperator& A,
                                GenericVector& x, const GenericVector& b);

    /// Solve linear system A^Tx = b
    std::size_t solve_transpose(const PETScMatrix& A, PETScVector& x,
                                const PETScVector& b);

    /// Sets the prefix used by PETSc when searching the options
    /// database
    void set_options_prefix(std::string options_prefix);

    /// Returns the prefix used by PETSc when searching the options
    /// database
    std::string get_options_prefix() const;

    /// Set options from the PETSc options database
    void set_from_options() const;

    /// Returns the MPI communicator
    MPI_Comm mpi_comm() const;

    /// Return informal string representation (pretty-print)
    std::string str(bool verbose) const;

    /// Return PETSc KSP pointer
    KSP ksp() const;

    /// Return a list of available solver methods
    static std::map<std::string, std::string> methods();

    /// Default parameter values
    static Parameters default_parameters();

    friend class PETScSNESSolver;
    friend class PETScTAOSolver;

  private:

    const MatSolverPackage _solver_package;

    // Available LU solvers
    static std::map<std::string, const MatSolverPackage> _methods;

    // Whether those solvers support Cholesky
    static std::map<const MatSolverPackage, bool> _methods_cholesky;

    // Available LU solvers descriptions
    static const std::map<std::string, std::string> _methods_descr;

    // Select LU solver type
    static const MatSolverPackage select_solver(MPI_Comm comm, std::string& method);

    // Does an LU solver support Cholesky?
    static bool solver_has_cholesky(const MatSolverPackage package);

    // Configure PETSc options
    void configure_ksp(const MatSolverPackage solver_package);

    // Print pre-solve report
    void pre_report(const PETScMatrix& A) const;

    // PETSc solver pointer
    KSP _ksp;

    // Operator (the matrix)
    std::shared_ptr<const PETScMatrix> _matA;

  };

}

#endif

#endif