newton_solver.h

Go to the documentation of this file.

// The libMesh Finite Element Library.
// Copyright (C) 2002-2018 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner

// This library 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 2.1 of the License, or (at your option) any later version.

// This library 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 this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA



#ifndef LIBMESH_NEWTON_SOLVER_H
#define LIBMESH_NEWTON_SOLVER_H

// Local includes
#include "libmesh/libmesh_common.h"
#include "libmesh/linear_solver.h"
#include "libmesh/reference_counted_object.h"
#include "libmesh/diff_solver.h"

// C++ includes

namespace libMesh
{

class NewtonSolver : public DiffSolver
{
public:
  explicit
  NewtonSolver (sys_type & system);

  virtual ~NewtonSolver ();

  typedef DiffSolver Parent;

  virtual void init () override;

  virtual void reinit () override;

  virtual unsigned int solve () override;

  LinearSolver<Number> & get_linear_solver()
  { libmesh_assert(_linear_solver);
    return *_linear_solver;
  }

  const LinearSolver<Number> & get_linear_solver() const
  { libmesh_assert(_linear_solver);
    return *_linear_solver;
  }

  bool require_residual_reduction;

  bool require_finite_residual;

  bool brent_line_search;

  bool track_linear_convergence;

  Real minsteplength;

  Real linear_tolerance_multiplier;

protected:

  std::unique_ptr<LinearSolver<Number>> _linear_solver;

  Real line_search(Real tol,
                   Real last_residual,
                   Real & current_residual,
                   NumericVector<Number> & newton_iterate,
                   const NumericVector<Number> & linear_solution);

  void print_convergence(unsigned int step_num,
                         Real current_residual,
                         Real step_norm,
                         bool linear_solve_finished);

  bool test_convergence(Real current_residual,
                        Real step_norm,
                        bool linear_solve_finished);
};


} // namespace libMesh


#endif // LIBMESH_NEWTON_SOLVER_H