theta_timestepping.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2010 - 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.md at
// the top level directory of deal.II.
//
// ---------------------------------------------------------------------


#ifndef dealii_theta_timestepping_h
#define dealii_theta_timestepping_h

#include <deal.II/algorithms/operator.h>
#include <deal.II/algorithms/timestep_control.h>

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

DEAL_II_NAMESPACE_OPEN

class ParameterHandler;

namespace Algorithms
{
  struct TimestepData
  {
    double time;
    double step;
  };

  template <typename VectorType>
  class ThetaTimestepping : public OperatorBase
  {
  public:
    ThetaTimestepping(OperatorBase &op_explicit, OperatorBase &op_implicit);

    virtual void
    operator()(AnyData &out, const AnyData &in) override;

    virtual void
    notify(const Event &) override;

    void
    set_output(OutputOperator<VectorType> &output);

    static void
    declare_parameters(ParameterHandler &param);

    void
    parse_parameters(ParameterHandler &param);

    double
    current_time() const;

    double
    theta() const;

    double
    theta(double new_theta);

    const TimestepData &
    explicit_data() const;

    const TimestepData &
    implicit_data() const;

    TimestepControl &
    timestep_control();

  private:
    TimestepControl control;

    double vtheta;
    bool adaptive;

    TimestepData d_explicit;

    TimestepData d_implicit;


    SmartPointer<OperatorBase, ThetaTimestepping<VectorType>> op_explicit;

    SmartPointer<OperatorBase, ThetaTimestepping<VectorType>> op_implicit;

    SmartPointer<OutputOperator<VectorType>, ThetaTimestepping<VectorType>>
      output;
  };


  template <typename VectorType>
  inline const TimestepData &
  ThetaTimestepping<VectorType>::explicit_data() const
  {
    return d_explicit;
  }


  template <typename VectorType>
  inline const TimestepData &
  ThetaTimestepping<VectorType>::implicit_data() const
  {
    return d_implicit;
  }


  template <typename VectorType>
  inline TimestepControl &
  ThetaTimestepping<VectorType>::timestep_control()
  {
    return control;
  }

  template <typename VectorType>
  inline void
  ThetaTimestepping<VectorType>::set_output(OutputOperator<VectorType> &out)
  {
    output = &out;
  }


  template <typename VectorType>
  inline double
  ThetaTimestepping<VectorType>::theta() const
  {
    return vtheta;
  }


  template <typename VectorType>
  inline double
  ThetaTimestepping<VectorType>::theta(double new_theta)
  {
    const double tmp = vtheta;
    vtheta           = new_theta;
    return tmp;
  }


  template <typename VectorType>
  inline double
  ThetaTimestepping<VectorType>::current_time() const
  {
    return control.now();
  }
} // namespace Algorithms

DEAL_II_NAMESPACE_CLOSE

#endif