/*
  Copyright 2012 SINTEF ICT, Applied Mathematics.

  This file is part of the Open Porous Media project (OPM).

  OPM is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  OPM 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 General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with OPM.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef OPM_LINEARSOLVERUMFPACK_HEADER_INCLUDED
#define OPM_LINEARSOLVERUMFPACK_HEADER_INCLUDED


#include <opm/core/linalg/LinearSolverInterface.hpp>


namespace Opm
{


    /// Concrete class encapsulating the UMFPACK direct linear solver.
    class LinearSolverUmfpack : public LinearSolverInterface
    {
    public:
        /// Default constructor.
        LinearSolverUmfpack();

        /// Destructor.
        virtual ~LinearSolverUmfpack();

        using LinearSolverInterface::solve;

        /// Solve a linear system, with a matrix given in compressed sparse row format.
        /// \param[in] size        # of rows in matrix
        /// \param[in] nonzeros    # of nonzeros elements in matrix
        /// \param[in] ia          array of length (size + 1) containing start and end indices for each row
        /// \param[in] ja          array of length nonzeros containing column numbers for the nonzero elements
        /// \param[in] sa          array of length nonzeros containing the values of the nonzero elements
        /// \param[in] rhs         array of length size containing the right hand side
        /// \param[inout] solution array of length size to which the solution will be written, may also be used
        ///                        as initial guess by iterative solvers.
        virtual LinearSolverReport solve(const int size,
                                         const int nonzeros,
                                         const int* ia,
                                         const int* ja,
                                         const double* sa,
                                         const double* rhs,
                                         double* solution,
                                         const boost::any& add=boost::any()) const;

        /// Set tolerance for the linear solver.
        /// \param[in] tol         tolerance value
        /// Not used for UMFPACK solver.
        virtual void setTolerance(const double /*tol*/);

        /// Get tolerance for the linear solver.
        /// \param[out] tolerance value
        /// Not used for UMFPACK solver. Returns -1.
        virtual double getTolerance() const;


    };


} // namespace Opm



#endif // OPM_LINEARSOLVERUMFPACK_HEADER_INCLUDED