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// 
//  
//  chaos~
//  Copyright (C) 2004  Tim Blechmann
//  
//  This program 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 2 of the License, or
//  (at your option) any later version.
//  
//  This program 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 this program; see the file COPYING.  If not, write to
//  the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
//  Boston, MA 02111-1307, USA.

#include "ode_base.hpp"
#include <cmath>

//  driven van_der_pol:
//      d2u/dt2 + a*(u*u -1)*du/dt + u = k * cos(Omega*t)
//  equivalent:
//      du1/dt = u2
//      du2/dt = -a*(u1*u1 - 1)*u2 - u1 + k*cos(u3)
//      du3/dt = Omega
//  taken from Willi-Hans Steeb: Chaos and Fractals

class driven_van_der_pol
	: public ode_base
{
public:
	driven_van_der_pol()
	{
		m_num_eq = 2;
		m_data = new data_t[m_num_eq];

		CHAOS_SYS_INIT(method,0);
		CHAOS_SYS_INIT(dt,0.01);

		CHAOS_SYS_INIT(u1,0.8);
		CHAOS_SYS_INIT(u2,0.6);
		CHAOS_SYS_INIT(u3,0.4);

		CHAOS_SYS_INIT(a,5);
		CHAOS_SYS_INIT(Omega,2.466);
		CHAOS_SYS_INIT(k,5);

		ode_base_alloc();
	}
	
	~driven_van_der_pol()
	{
		ode_base_free();
		delete m_data;
	}

	virtual void m_system(data_t* deriv, data_t* data)
	{
		data_t u1 = data[0], u2 = data[1], u3 = data[2];
		
		deriv[0] = u2;
		deriv[1] = - CHAOS_PARAMETER(a) * (u1*u1 -1) * u2 - u1 + 
			CHAOS_PARAMETER(k)*cos(u3);
		deriv[2] = CHAOS_PARAMETER(Omega);
	}
	
	CHAOS_SYSVAR_FUNCS(u1, 0);
	CHAOS_SYSVAR_FUNCS(u2, 1);
	CHAOS_SYSVAR_FUNCS(u3, 2);

	CHAOS_SYSPAR_FUNCS(a);
	CHAOS_SYSPAR_FUNCS(k);
	CHAOS_SYSPAR_FUNCS(Omega);
};


#define DRIVEN_VAN_DER_POL_CALLBACKS			\
ODE_CALLBACKS;									\
CHAOS_SYS_CALLBACKS(u1);						\
CHAOS_SYS_CALLBACKS(u2);						\
CHAOS_SYS_CALLBACKS(a);							\
CHAOS_SYS_CALLBACKS(k);							\
CHAOS_SYS_CALLBACKS(Omega);

#define DRIVEN_VAN_DER_POL_ATTRIBUTES			\
ODE_ATTRIBUTES;									\
CHAOS_SYS_ATTRIBUTE(u1);						\
CHAOS_SYS_ATTRIBUTE(u2);						\
CHAOS_SYS_ATTRIBUTE(a);							\
CHAOS_SYS_ATTRIBUTE(k);							\
CHAOS_SYS_ATTRIBUTE(Omega);