Click here to Skip to main content
15,895,557 members
Articles / Programming Languages / CUDA

odeint v2 - Solving ordinary differential equations in C++

Rate me:
Please Sign up or sign in to vote.
4.64/5 (18 votes)
19 Oct 2011CPOL19 min read 130K   2.8K   34  
odeint v2 - Solving ordinary differential equations in C++
#include <boost/array.hpp>

//#include <boost/numeric/odeint/stepper/explicit_generic_rk.hpp>
#include <boost/numeric/odeint/stepper/runge_kutta4.hpp>
#include <boost/numeric/odeint/algebra/array_algebra.hpp>

#include "rk_performance_test_case.hpp"

#include "lorenz.hpp"

using namespace boost::numeric::odeint;

typedef boost::array< double , 3 > state_type;
/*typedef explicit_generic_rk< 4 , 4 , state_type , double , state_type , double , array_algebra > rk4_type;

typedef rk4_type::coef_a_type coef_a_type;
typedef rk4_type::coef_b_type coef_b_type;
typedef rk4_type::coef_c_type coef_c_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 coef_a_type a = fusion::make_vector( a1 , a2 , a3 );
const coef_b_type b = {{ 1.0/6 , 1.0/3 , 1.0/3 , 1.0/6 }};
const coef_c_type c = {{ 0.0 , 0.5 , 0.5 , 1.0 }};
*/

typedef runge_kutta4< state_type , double , state_type , double , array_algebra > rk4_type;


class rk4_wrapper
{

public:

    rk4_wrapper()
    { }

    void reset_init_cond()
    {
        m_x[0] = 10.0 * rand() / RAND_MAX;
        m_x[1] = 10.0 * rand() / RAND_MAX;
        m_x[2] = 10.0 * rand() / RAND_MAX;
        m_t = 0.0;
    }

    inline void do_step( const double dt )
    {
        m_stepper.do_step( lorenz(), m_x , m_t , dt );
    }

    double state( const size_t i ) const
    { return m_x[i]; }

private:
    state_type m_x;
    double m_t;
    rk4_type m_stepper;
};



int main()
{
    srand( 12312354 );

    rk4_wrapper stepper;

    run( stepper );
}

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Germany Germany
This member has not yet provided a Biography. Assume it's interesting and varied, and probably something to do with programming.

Comments and Discussions