homotopyode.h

利用C

// Copyright (C) 2005-2006 Anders Logg.
// Licensed under the GNU LGPL Version 2.1.
//
// First added:  2005
// Last changed: 2006-08-21

#ifndef __HOMOTOPY_ODE_H
#define __HOMOTOPY_ODE_H

#include <dolfin/common/types.h>
#include "ComplexODE.h"

namespace dolfin
{

  class Homotopy;

  /// This is the base class for complex homotopy ODEs. One ODE is
  /// generated by the class Homotopy for each homotopy path.
  
  class HomotopyODE : public ComplexODE
  {
  public:
  
    /// Current state, solving ODE or playing end game
    enum State { ode, endgame };

    /// Constructor
    HomotopyODE(Homotopy& homotopy, uint n, real T);

    /// Destructor
    ~HomotopyODE();

    /// Return initial value for given component
    void z0(complex z[]);

    /// Evaluate right-hand side
    void f(const complex z[], real t, complex y[]);
    
    /// Compute product y = Mx for implicit system
    void M(const complex x[], complex y[], const complex z[], real t);

    /// Compute product y = Jx for Jacobian J
    void J(const complex x[], complex y[], const complex u[], real t);

    /// Update ODE, return false to stop (optional)
    bool update(const complex z[], real t, bool end);

    /// Get state, solving ODE or playing end game
    State state();

  private:

    // Monitor homotopy
    void monitor(const complex z[], real t);

    // The homotopy
    Homotopy& homotopy;

    // Size of system
    uint n;

    // Current state
    State _state;

    // Array of values used for temporary storage
    complex* tmp;

  };

}

#endif