256 lines
11 KiB
Plaintext
256 lines
11 KiB
Plaintext
|
/*
|
||
|
|
[auto_generated]
|
||
|
|
boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp
|
||
|
|
|
||
|
|
[begin_description]
|
||
|
|
Implementation of the generic Runge Kutta error stepper. Base class for many RK error steppers.
|
||
|
|
[end_description]
|
||
|
|
|
||
|
|
Copyright 2011-2013 Mario Mulansky
|
||
|
|
Copyright 2011-2013 Karsten Ahnert
|
||
|
|
Copyright 2012 Christoph Koke
|
||
|
|
|
||
|
|
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)
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
#ifndef BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_ERROR_GENERIC_RK_HPP_INCLUDED
|
||
|
|
#define BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_ERROR_GENERIC_RK_HPP_INCLUDED
|
||
|
|
|
||
|
|
#include <boost/numeric/odeint/stepper/base/explicit_error_stepper_base.hpp>
|
||
|
|
|
||
|
|
#include <boost/numeric/odeint/algebra/default_operations.hpp>
|
||
|
|
#include <boost/numeric/odeint/algebra/range_algebra.hpp>
|
||
|
|
#include <boost/numeric/odeint/algebra/algebra_dispatcher.hpp>
|
||
|
|
#include <boost/numeric/odeint/algebra/operations_dispatcher.hpp>
|
||
|
|
#include <boost/numeric/odeint/stepper/detail/generic_rk_algorithm.hpp>
|
||
|
|
#include <boost/numeric/odeint/stepper/detail/generic_rk_call_algebra.hpp>
|
||
|
|
#include <boost/numeric/odeint/stepper/detail/generic_rk_operations.hpp>
|
||
|
|
|
||
|
|
#include <boost/numeric/odeint/util/state_wrapper.hpp>
|
||
|
|
#include <boost/numeric/odeint/util/is_resizeable.hpp>
|
||
|
|
#include <boost/numeric/odeint/util/resizer.hpp>
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
namespace boost {
|
||
|
|
namespace numeric {
|
||
|
|
namespace odeint {
|
||
|
|
|
||
|
|
|
||
|
|
template<
|
||
|
|
size_t StageCount,
|
||
|
|
size_t Order,
|
||
|
|
size_t StepperOrder ,
|
||
|
|
size_t ErrorOrder ,
|
||
|
|
class State ,
|
||
|
|
class Value = double ,
|
||
|
|
class Deriv = State ,
|
||
|
|
class Time = Value ,
|
||
|
|
class Algebra = typename algebra_dispatcher< State >::algebra_type ,
|
||
|
|
class Operations = typename operations_dispatcher< State >::operations_type ,
|
||
|
|
class Resizer = initially_resizer
|
||
|
|
>
|
||
|
|
#ifndef DOXYGEN_SKIP
|
||
|
|
class explicit_error_generic_rk
|
||
|
|
: public explicit_error_stepper_base<
|
||
|
|
explicit_error_generic_rk< StageCount , Order , StepperOrder , ErrorOrder , State ,
|
||
|
|
Value , Deriv , Time , Algebra , Operations , Resizer > ,
|
||
|
|
Order , StepperOrder , ErrorOrder , State , Value , Deriv , Time , Algebra ,
|
||
|
|
Operations , Resizer >
|
||
|
|
#else
|
||
|
|
class explicit_error_generic_rk : public explicit_error_stepper_base
|
||
|
|
#endif
|
||
|
|
{
|
||
|
|
|
||
|
|
public:
|
||
|
|
#ifndef DOXYGEN_SKIP
|
||
|
|
typedef explicit_error_stepper_base<
|
||
|
|
explicit_error_generic_rk< StageCount , Order , StepperOrder , ErrorOrder , State ,
|
||
|
|
Value , Deriv , Time , Algebra , Operations , Resizer > ,
|
||
|
|
Order , StepperOrder , ErrorOrder , State , Value , Deriv , Time , Algebra ,
|
||
|
|
Operations , Resizer > stepper_base_type;
|
||
|
|
#else
|
||
|
|
typedef explicit_stepper_base< ... > stepper_base_type;
|
||
|
|
#endif
|
||
|
|
typedef typename stepper_base_type::state_type state_type;
|
||
|
|
typedef typename stepper_base_type::wrapped_state_type wrapped_state_type;
|
||
|
|
typedef typename stepper_base_type::value_type value_type;
|
||
|
|
typedef typename stepper_base_type::deriv_type deriv_type;
|
||
|
|
typedef typename stepper_base_type::wrapped_deriv_type wrapped_deriv_type;
|
||
|
|
typedef typename stepper_base_type::time_type time_type;
|
||
|
|
typedef typename stepper_base_type::algebra_type algebra_type;
|
||
|
|
typedef typename stepper_base_type::operations_type operations_type;
|
||
|
|
typedef typename stepper_base_type::resizer_type resizer_type;
|
||
|
|
#ifndef DOXYGEN_SKIP
|
||
|
|
typedef explicit_error_generic_rk< StageCount , Order , StepperOrder , ErrorOrder , State ,
|
||
|
|
Value , Deriv , Time , Algebra , Operations , Resizer > stepper_type;
|
||
|
|
#endif
|
||
|
|
typedef detail::generic_rk_algorithm< StageCount , Value , Algebra , Operations > rk_algorithm_type;
|
||
|
|
|
||
|
|
typedef typename rk_algorithm_type::coef_a_type coef_a_type;
|
||
|
|
typedef typename rk_algorithm_type::coef_b_type coef_b_type;
|
||
|
|
typedef typename rk_algorithm_type::coef_c_type coef_c_type;
|
||
|
|
|
||
|
|
static const size_t stage_count = StageCount;
|
||
|
|
|
||
|
|
private:
|
||
|
|
|
||
|
|
|
||
|
|
public:
|
||
|
|
|
||
|
|
// we use an explicit_generic_rk to do the normal rk step
|
||
|
|
// and add a separate calculation of the error estimate afterwards
|
||
|
|
explicit_error_generic_rk( const coef_a_type &a ,
|
||
|
|
const coef_b_type &b ,
|
||
|
|
const coef_b_type &b2 ,
|
||
|
|
const coef_c_type &c ,
|
||
|
|
const algebra_type &algebra = algebra_type() )
|
||
|
|
: stepper_base_type( algebra ) , m_rk_algorithm( a , b , c ) , m_b2( b2 )
|
||
|
|
{ }
|
||
|
|
|
||
|
|
|
||
|
|
template< class System , class StateIn , class DerivIn , class StateOut , class Err >
|
||
|
|
void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt ,
|
||
|
|
time_type t , StateOut &out , time_type dt , Err &xerr )
|
||
|
|
{
|
||
|
|
// normal step
|
||
|
|
do_step_impl( system , in , dxdt , t , out , dt );
|
||
|
|
|
||
|
|
// additionally, perform the error calculation
|
||
|
|
detail::template generic_rk_call_algebra< StageCount , algebra_type >()( stepper_base_type::m_algebra ,
|
||
|
|
xerr , dxdt , m_F , detail::generic_rk_scale_sum_err< StageCount , operations_type , value_type , time_type >( m_b2 , dt) );
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
template< class System , class StateIn , class DerivIn , class StateOut >
|
||
|
|
void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt ,
|
||
|
|
time_type t , StateOut &out , time_type dt )
|
||
|
|
{
|
||
|
|
m_resizer.adjust_size( in , detail::bind( &stepper_type::template resize_impl< StateIn > , detail::ref( *this ) , detail::_1 ) );
|
||
|
|
|
||
|
|
// actual calculation done in generic_rk.hpp
|
||
|
|
m_rk_algorithm.do_step( stepper_base_type::m_algebra , system , in , dxdt , t , out , dt , m_x_tmp.m_v , m_F );
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
template< class StateIn >
|
||
|
|
void adjust_size( const StateIn &x )
|
||
|
|
{
|
||
|
|
resize_impl( x );
|
||
|
|
stepper_base_type::adjust_size( x );
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
private:
|
||
|
|
|
||
|
|
template< class StateIn >
|
||
|
|
bool resize_impl( const StateIn &x )
|
||
|
|
{
|
||
|
|
bool resized( false );
|
||
|
|
resized |= adjust_size_by_resizeability( m_x_tmp , x , typename is_resizeable<state_type>::type() );
|
||
|
|
for( size_t i = 0 ; i < StageCount-1 ; ++i )
|
||
|
|
{
|
||
|
|
resized |= adjust_size_by_resizeability( m_F[i] , x , typename is_resizeable<deriv_type>::type() );
|
||
|
|
}
|
||
|
|
return resized;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
rk_algorithm_type m_rk_algorithm;
|
||
|
|
coef_b_type m_b2;
|
||
|
|
|
||
|
|
resizer_type m_resizer;
|
||
|
|
|
||
|
|
wrapped_state_type m_x_tmp;
|
||
|
|
wrapped_deriv_type m_F[StageCount-1];
|
||
|
|
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
/********* DOXYGEN *********/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \class explicit_error_generic_rk
|
||
|
|
* \brief A generic implementation of explicit Runge-Kutta algorithms with error estimation. This class is as a
|
||
|
|
* base class for all explicit Runge-Kutta steppers with error estimation.
|
||
|
|
*
|
||
|
|
* This class implements the explicit Runge-Kutta algorithms with error estimation in a generic way.
|
||
|
|
* The Butcher tableau is passed to the stepper which constructs the stepper scheme with the help of a
|
||
|
|
* template-metaprogramming algorithm. ToDo : Add example!
|
||
|
|
*
|
||
|
|
* This class derives explicit_error_stepper_base which provides the stepper interface.
|
||
|
|
*
|
||
|
|
* \tparam StageCount The number of stages of the Runge-Kutta algorithm.
|
||
|
|
* \tparam Order The order of a stepper if the stepper is used without error estimation.
|
||
|
|
* \tparam StepperOrder The order of a step if the stepper is used with error estimation. Usually Order and StepperOrder have
|
||
|
|
* the same value.
|
||
|
|
* \tparam ErrorOrder The order of the error step if the stepper is used with error estimation.
|
||
|
|
* \tparam State The type representing the state of the ODE.
|
||
|
|
* \tparam Value The floating point type which is used in the computations.
|
||
|
|
* \tparam Time The type representing the independent variable - the time - of the ODE.
|
||
|
|
* \tparam Algebra The algebra type.
|
||
|
|
* \tparam Operations The operations type.
|
||
|
|
* \tparam Resizer The resizer policy type.
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \fn explicit_error_generic_rk::explicit_error_generic_rk( const coef_a_type &a , const coef_b_type &b , const coef_b_type &b2 , const coef_c_type &c , const algebra_type &algebra )
|
||
|
|
* \brief Constructs the explicit_error_generik_rk class with the given parameters a, b, b2 and c. See examples section for details on the coefficients.
|
||
|
|
*
|
||
|
|
* \param a Triangular matrix of parameters b in the Butcher tableau.
|
||
|
|
* \param b Last row of the butcher tableau.
|
||
|
|
* \param b2 Parameters for lower-order evaluation to estimate the error.
|
||
|
|
* \param c Parameters to calculate the time points in the Butcher tableau.
|
||
|
|
* \param algebra A copy of algebra is made and stored inside explicit_stepper_base.
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \fn explicit_error_generic_rk::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt , time_type t , StateOut &out , time_type dt , Err &xerr )
|
||
|
|
* \brief This method performs one step. The derivative `dxdt` of `in` at the time `t` is passed to the method.
|
||
|
|
* The result is updated out-of-place, hence the input is in `in` and the output in `out`. Futhermore, an
|
||
|
|
* estimation of the error is stored in `xerr`. `do_step_impl` is used by explicit_error_stepper_base.
|
||
|
|
*
|
||
|
|
* \param system The system function to solve, hence the r.h.s. of the ODE. It must fulfill the
|
||
|
|
* Simple System concept.
|
||
|
|
* \param in The state of the ODE which should be solved. in is not modified in this method
|
||
|
|
* \param dxdt The derivative of x at t.
|
||
|
|
* \param t The value of the time, at which the step should be performed.
|
||
|
|
* \param out The result of the step is written in out.
|
||
|
|
* \param dt The step size.
|
||
|
|
* \param xerr The result of the error estimation is written in xerr.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \fn explicit_error_generic_rk::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt , time_type t , StateOut &out , time_type dt )
|
||
|
|
* \brief This method performs one step. The derivative `dxdt` of `in` at the time `t` is passed to the method.
|
||
|
|
* The result is updated out-of-place, hence the input is in `in` and the output in `out`.
|
||
|
|
* Access to this step functionality is provided by explicit_stepper_base and
|
||
|
|
* `do_step_impl` should not be called directly.
|
||
|
|
*
|
||
|
|
* \param system The system function to solve, hence the r.h.s. of the ODE. It must fulfill the
|
||
|
|
* Simple System concept.
|
||
|
|
* \param in The state of the ODE which should be solved. in is not modified in this method
|
||
|
|
* \param dxdt The derivative of x at t.
|
||
|
|
* \param t The value of the time, at which the step should be performed.
|
||
|
|
* \param out The result of the step is written in out.
|
||
|
|
* \param dt The step size.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \fn explicit_error_generic_rk::adjust_size( const StateIn &x )
|
||
|
|
* \brief Adjust the size of all temporaries in the stepper manually.
|
||
|
|
* \param x A state from which the size of the temporaries to be resized is deduced.
|
||
|
|
*/
|
||
|
|
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
#endif // BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_ERROR_GENERIC_RK_HPP_INCLUDED
|