odeint/test/generic_stepper.cpp
2014-03-26 08:20:59 +01:00

105 lines
2.8 KiB
C++

/*
[auto_generated]
libs/numeric/odeint/test/generic_stepper.cpp
[begin_description]
This file tests the generic stepper.
[end_description]
Copyright 2011 Mario Mulansky
Copyright 2012 Karsten Ahnert
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE_1_0.txt or
copy at http://www.boost.org/LICENSE_1_0.txt)
*/
// disable checked iterator warning for msvc
#include <boost/config.hpp>
#ifdef BOOST_MSVC
#pragma warning(disable:4996)
#endif
#define BOOST_TEST_MODULE odeint_generic_stepper
#include <iostream>
#include <utility>
#include <boost/test/unit_test.hpp>
#include <boost/numeric/odeint/stepper/explicit_generic_rk.hpp>
#include <boost/numeric/odeint/stepper/runge_kutta4.hpp>
#include <boost/numeric/odeint/stepper/runge_kutta4_classic.hpp>
#include <boost/array.hpp>
using namespace boost::unit_test;
using namespace boost::numeric::odeint;
namespace fusion = boost::fusion;
typedef double value_type;
typedef boost::array< value_type , 2 > state_type;
void sys( const state_type &x , state_type &dxdt , const value_type &t )
{
dxdt[ 0 ] = x[ 0 ] + 2 * x[ 1 ];
dxdt[ 1 ] = x[ 1 ];
}
typedef explicit_generic_rk< 4 , 4 , state_type> rk_generic_type;
typedef runge_kutta4< state_type > rk4_generic_type;
const boost::array< double , 1 > a1 = {{ 0.5 }};
const boost::array< double , 2 > a2 = {{ 0.0 , 0.5 }};
const boost::array< double , 3 > a3 = {{ 0.0 , 0.0 , 1.0 }};
const rk_generic_type::coef_a_type a = fusion::make_vector( a1 , a2 , a3 );
const rk_generic_type::coef_b_type b = {{ 1.0/6 , 1.0/3 , 1.0/3 , 1.0/6 }};
const rk_generic_type::coef_c_type c = {{ 0.0 , 0.5 , 0.5 , 1.0 }};
typedef runge_kutta4_classic< state_type > rk4_type;
BOOST_AUTO_TEST_SUITE( generic_stepper_test )
BOOST_AUTO_TEST_CASE( test_generic_stepper )
{
//simultaneously test copying
rk_generic_type rk_generic_( a , b , c );
rk_generic_type rk_generic = rk_generic_;
rk4_generic_type rk4_generic_;
rk4_generic_type rk4_generic = rk4_generic_;
//std::cout << stepper;
rk4_type rk4_;
rk4_type rk4 = rk4_;
typedef rk_generic_type::state_type state_type;
typedef rk_generic_type::value_type stepper_value_type;
typedef rk_generic_type::deriv_type deriv_type;
typedef rk_generic_type::time_type time_type;
state_type x = {{ 0.0 , 1.0 }};
state_type y = x;
state_type z = x;
rk_generic.do_step( sys , x , 0.0 , 0.1 );
rk4_generic.do_step( sys , y , 0.0 , 0.1 );
rk4.do_step( sys , z , 0.0 , 0.1 );
BOOST_CHECK_NE( 0.0 , x[0] );
BOOST_CHECK_NE( 1.0 , x[1] );
// compare with analytic solution of above system
BOOST_CHECK_EQUAL( x[0] , y[0] );
BOOST_CHECK_EQUAL( x[1] , y[1] );
BOOST_CHECK_EQUAL( x[0] , z[0] );
BOOST_CHECK_EQUAL( x[1] , z[1] );
}
BOOST_AUTO_TEST_SUITE_END()