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/*
* lorenz_mp.cpp
*
* This example demonstrates how odeint can be used with boost.multiprecision.
*
* Copyright 2011-2012 Karsten Ahnert
* Copyright 2013 Mario Mulansky
*
* 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)
*/
#include <iostream>
//[ mp_lorenz_defs
#include <boost/numeric/odeint.hpp>
#include <boost/multiprecision/cpp_dec_float.hpp>
using namespace std;
using namespace boost::numeric::odeint;
typedef boost::multiprecision::cpp_dec_float_50 value_type;
typedef boost::array< value_type , 3 > state_type;
//]
//[ mp_lorenz_rhs
struct lorenz
{
void operator()( const state_type &x , state_type &dxdt , value_type t ) const
{
const value_type sigma( 10 );
const value_type R( 28 );
const value_type b( value_type( 8 ) / value_type( 3 ) );
dxdt[0] = sigma * ( x[1] - x[0] );
dxdt[1] = R * x[0] - x[1] - x[0] * x[2];
dxdt[2] = -b * x[2] + x[0] * x[1];
}
};
//]
struct streaming_observer
{
std::ostream& m_out;
streaming_observer( std::ostream &out ) : m_out( out ) { }
template< class State , class Time >
void operator()( const State &x , Time t ) const
{
m_out << t;
for( size_t i=0 ; i<x.size() ; ++i ) m_out << "\t" << x[i] ;
m_out << "\n";
}
};
int main( int argc , char **argv )
{
//[ mp_lorenz_int
state_type x = {{ value_type( 10.0 ) , value_type( 10.0 ) , value_type( 10.0 ) }};
cout.precision( 50 );
integrate_const( runge_kutta4< state_type , value_type >() ,
lorenz() , x , value_type( 0.0 ) , value_type( 10.0 ) , value_type( value_type( 1.0 ) / value_type( 10.0 ) ) ,
streaming_observer( cout ) );
//]
return 0;
}
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