timestep_control.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2010 - 2017 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_time_step_control_h
#define dealii_time_step_control_h

#include <deal.II/base/subscriptor.h>
#include <deal.II/base/smartpointer.h>
#include <deal.II/lac/vector_memory.h>
#include <cstdio>

DEAL_II_NAMESPACE_OPEN

class ParameterHandler;

namespace Algorithms
{
  class TimestepControl : public Subscriptor
  {
  public:
    enum Strategy
    {
      uniform,
      doubling
    };

    TimestepControl (double start = 0.,
                     double final = 1.,
                     double tolerance = 1.e-2,
                     double start_step = 1.e-2,
                     double print_step = -1.,
                     double max_step = 1.);

    static void declare_parameters (ParameterHandler &param);
    void parse_parameters (ParameterHandler &param);

    double start () const;
    double final () const;
    double tolerance () const;
    double step () const;

    double now () const;

    bool advance ();

    void start (double);
    void final (double);
    void tolerance (double);
    void strategy (Strategy);

    void start_step (const double step);

    void max_step (double);

    void restart ();
    bool print ();
    void file_name_format (const char *);
    const char *file_name_format ();
  private:

    double start_val;
    double final_val;
    double tolerance_val;
    Strategy strategy_val;
    double start_step_val;
    double max_step_val;
    double min_step_val;
    double current_step_val;
    double step_val;

    double now_val;
    double print_step;
    double next_print_val;

    char format[30];
  };


  inline double
  TimestepControl::start () const
  {
    return start_val;
  }


  inline double
  TimestepControl::final () const
  {
    return final_val;
  }


  inline double
  TimestepControl::step () const
  {
    return current_step_val;
  }


  inline double
  TimestepControl::tolerance () const
  {
    return tolerance_val;
  }


  inline double
  TimestepControl::now () const
  {
    return now_val;
  }


  inline void
  TimestepControl::start (double t)
  {
    start_val = t;
  }


  inline void
  TimestepControl::final (double t)
  {
    final_val = t;
  }


  inline void
  TimestepControl::tolerance (double t)
  {
    tolerance_val = t;
  }


  inline void
  TimestepControl::strategy (Strategy t)
  {
    strategy_val = t;
  }


  inline void
  TimestepControl::start_step (const double t)
  {
    start_step_val = t;
  }


  inline void
  TimestepControl::max_step (double t)
  {
    max_step_val = t;
  }


  inline void
  TimestepControl::restart ()
  {
    now_val = start_val;
    step_val = start_step_val;
    current_step_val = step_val;
    if (print_step > 0.)
      next_print_val = now_val + print_step;
    else
      next_print_val = now_val - 1.;
  }


  inline void
  TimestepControl::file_name_format (const char *fmt)
  {
    strcpy(format, fmt);
  }


  inline const char *
  TimestepControl::file_name_format ()
  {
    return format;
  }
}

DEAL_II_NAMESPACE_CLOSE

#endif