| /* |
| * rosenbrock4.cpp |
| * |
| * Copyright 2010-2012 Mario Mulansky |
| * Copyright 2011-2012 Karsten Ahnert |
| * Copyright 2012 Andreas Angelopoulos |
| * |
| * 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> |
| #include <fstream> |
| #include <utility> |
| |
| #include <boost/numeric/odeint.hpp> |
| |
| #include <boost/phoenix/core.hpp> |
| |
| #include <boost/phoenix/core.hpp> |
| #include <boost/phoenix/operator.hpp> |
| |
| using namespace std; |
| using namespace boost::numeric::odeint; |
| namespace phoenix = boost::phoenix; |
| |
| |
| |
| //[ stiff_system_definition |
| typedef boost::numeric::ublas::vector< double > vector_type; |
| typedef boost::numeric::ublas::matrix< double > matrix_type; |
| |
| struct stiff_system |
| { |
| void operator()( const vector_type &x , vector_type &dxdt , double /* t */ ) |
| { |
| dxdt[ 0 ] = -101.0 * x[ 0 ] - 100.0 * x[ 1 ]; |
| dxdt[ 1 ] = x[ 0 ]; |
| } |
| }; |
| |
| struct stiff_system_jacobi |
| { |
| void operator()( const vector_type & /* x */ , matrix_type &J , const double & /* t */ , vector_type &dfdt ) |
| { |
| J( 0 , 0 ) = -101.0; |
| J( 0 , 1 ) = -100.0; |
| J( 1 , 0 ) = 1.0; |
| J( 1 , 1 ) = 0.0; |
| dfdt[0] = 0.0; |
| dfdt[1] = 0.0; |
| } |
| }; |
| //] |
| |
| |
| |
| /* |
| //[ stiff_system_alternative_definition |
| typedef boost::numeric::ublas::vector< double > vector_type; |
| typedef boost::numeric::ublas::matrix< double > matrix_type; |
| |
| struct stiff_system |
| { |
| template< class State > |
| void operator()( const State &x , State &dxdt , double t ) |
| { |
| ... |
| } |
| }; |
| |
| struct stiff_system_jacobi |
| { |
| template< class State , class Matrix > |
| void operator()( const State &x , Matrix &J , const double &t , State &dfdt ) |
| { |
| ... |
| } |
| }; |
| //] |
| */ |
| |
| |
| |
| int main( int argc , char **argv ) |
| { |
| // typedef rosenbrock4< double > stepper_type; |
| // typedef rosenbrock4_controller< stepper_type > controlled_stepper_type; |
| // typedef rosenbrock4_dense_output< controlled_stepper_type > dense_output_type; |
| //[ integrate_stiff_system |
| vector_type x( 2 , 1.0 ); |
| |
| size_t num_of_steps = integrate_const( make_dense_output< rosenbrock4< double > >( 1.0e-6 , 1.0e-6 ) , |
| make_pair( stiff_system() , stiff_system_jacobi() ) , |
| x , 0.0 , 50.0 , 0.01 , |
| cout << phoenix::arg_names::arg2 << " " << phoenix::arg_names::arg1[0] << "\n" ); |
| //] |
| clog << num_of_steps << endl; |
| |
| |
| |
| // typedef runge_kutta_dopri5< vector_type > dopri5_type; |
| // typedef controlled_runge_kutta< dopri5_type > controlled_dopri5_type; |
| // typedef dense_output_runge_kutta< controlled_dopri5_type > dense_output_dopri5_type; |
| //[ integrate_stiff_system_alternative |
| |
| vector_type x2( 2 , 1.0 ); |
| |
| size_t num_of_steps2 = integrate_const( make_dense_output< runge_kutta_dopri5< vector_type > >( 1.0e-6 , 1.0e-6 ) , |
| stiff_system() , x2 , 0.0 , 50.0 , 0.01 , |
| cout << phoenix::arg_names::arg2 << " " << phoenix::arg_names::arg1[0] << "\n" ); |
| //] |
| clog << num_of_steps2 << endl; |
| |
| |
| return 0; |
| } |