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			8.5 KiB
		
	
	
	
		
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			247 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| /*
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|  [auto_generated]
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|  boost/numeric/odeint/stepper/explicit_generic_rk.hpp
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| 
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|  [begin_description]
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|  Implementation of the generic Runge-Kutta steppers. This is the base class for many Runge-Kutta steppers.
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|  [end_description]
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| 
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|  Copyright 2011-2013 Mario Mulansky
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|  Copyright 2011-2013 Karsten Ahnert
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|  Copyright 2012 Christoph Koke
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| 
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|  Distributed under the Boost Software License, Version 1.0.
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|  (See accompanying file LICENSE_1_0.txt or
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|  copy at http://www.boost.org/LICENSE_1_0.txt)
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|  */
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| 
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| 
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| #ifndef BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_GENERIC_RK_HPP_INCLUDED
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| #define BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_GENERIC_RK_HPP_INCLUDED
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| 
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| 
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| #include <boost/array.hpp>
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| 
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| 
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| #include <boost/numeric/odeint/stepper/base/explicit_stepper_base.hpp>
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| #include <boost/numeric/odeint/algebra/range_algebra.hpp>
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| #include <boost/numeric/odeint/algebra/default_operations.hpp>
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| #include <boost/numeric/odeint/algebra/algebra_dispatcher.hpp>
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| #include <boost/numeric/odeint/algebra/operations_dispatcher.hpp>
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| #include <boost/numeric/odeint/stepper/detail/generic_rk_algorithm.hpp>
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| 
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| #include <boost/numeric/odeint/util/state_wrapper.hpp>
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| #include <boost/numeric/odeint/util/is_resizeable.hpp>
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| #include <boost/numeric/odeint/util/resizer.hpp>
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| 
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| namespace boost {
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| namespace numeric {
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| namespace odeint {
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| 
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| //forward declarations
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| 
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| #ifndef DOXYGEN_SKIP
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| template<
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| size_t StageCount,
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| size_t Order,
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| class State ,
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| class Value = double ,
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| class Deriv = State ,
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| class Time = Value ,
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| class Algebra = typename algebra_dispatcher< State >::algebra_type ,
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| class Operations = typename operations_dispatcher< State >::operations_type ,
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| class Resizer = initially_resizer
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| >
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| class explicit_generic_rk;
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| 
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| 
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| struct stage_vector;
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| 
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| template< class T , class Constant >
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| struct array_wrapper
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| {
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|     typedef const typename boost::array< T , Constant::value > type;
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| };
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| 
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| template< class T , size_t i >
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| struct stage
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| {
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|     T c;
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|     boost::array< T , i > a;
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| };
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| 
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| 
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| template< class T , class Constant >
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| struct stage_wrapper
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| {
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|     typedef stage< T , Constant::value > type;
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| };
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| #endif
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| 
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| 
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| template<
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| size_t StageCount,
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| size_t Order,
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| class State ,
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| class Value ,
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| class Deriv ,
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| class Time ,
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| class Algebra ,
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| class Operations ,
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| class Resizer
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| >
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| #ifndef DOXYGEN_SKIP
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| class explicit_generic_rk : public explicit_stepper_base<
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| explicit_generic_rk< StageCount , Order , State , Value , Deriv , Time , Algebra , Operations , Resizer > ,
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| Order , State , Value , Deriv , Time , Algebra , Operations , Resizer >
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| #else
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| class explicit_generic_rk : public explicit_stepper_base
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| #endif
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| {
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| 
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| public:
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| 
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|     #ifndef DOXYGEN_SKIP
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|     typedef explicit_stepper_base<
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|             explicit_generic_rk< StageCount , Order , State , Value , Deriv ,Time , Algebra , Operations , Resizer > ,
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|             Order , State , Value , Deriv , Time , Algebra ,
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|             Operations , Resizer > stepper_base_type;
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|     #else
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|     typedef explicit_stepper_base< ... > stepper_base_type;
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|     #endif
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| 
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|     typedef typename stepper_base_type::state_type state_type;
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|     typedef typename stepper_base_type::wrapped_state_type wrapped_state_type;
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|     typedef typename stepper_base_type::value_type value_type;
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|     typedef typename stepper_base_type::deriv_type deriv_type;
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|     typedef typename stepper_base_type::wrapped_deriv_type wrapped_deriv_type;
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|     typedef typename stepper_base_type::time_type time_type;
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|     typedef typename stepper_base_type::algebra_type algebra_type;
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|     typedef typename stepper_base_type::operations_type operations_type;
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|     typedef typename stepper_base_type::resizer_type resizer_type;
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| 
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|     #ifndef DOXYGEN_SKIP
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|     typedef explicit_generic_rk< StageCount , Order , State , Value , Deriv ,Time , Algebra , Operations , Resizer > stepper_type;
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|     #endif 
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| 
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|     typedef detail::generic_rk_algorithm< StageCount , Value , Algebra , Operations > rk_algorithm_type;
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| 
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|     typedef typename rk_algorithm_type::coef_a_type coef_a_type;
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|     typedef typename rk_algorithm_type::coef_b_type coef_b_type;
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|     typedef typename rk_algorithm_type::coef_c_type coef_c_type;
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| 
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|     #ifndef DOXYGEN_SKIP
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|     static const size_t stage_count = StageCount;
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|     #endif
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| 
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| public:
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| 
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|     explicit_generic_rk( const coef_a_type &a , const coef_b_type &b , const coef_c_type &c ,
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|             const algebra_type &algebra = algebra_type() )
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|     : stepper_base_type( algebra ) , m_rk_algorithm( a , b , c )
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|     { }
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| 
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| 
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|     template< class System , class StateIn , class DerivIn , class StateOut >
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|     void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt ,
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|             time_type t , StateOut &out , time_type dt )
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|     {
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|         m_resizer.adjust_size( in , detail::bind( &stepper_type::template resize_impl< StateIn > , detail::ref( *this ) , detail::_1 ) );
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| 
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|         // actual calculation done in generic_rk.hpp
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|         m_rk_algorithm.do_step( stepper_base_type::m_algebra , system , in , dxdt , t , out , dt , m_x_tmp.m_v , m_F );
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|     }
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| 
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|     template< class StateIn >
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|     void adjust_size( const StateIn &x )
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|     {
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|         resize_impl( x );
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|         stepper_base_type::adjust_size( x );
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|     }
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| 
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| private:
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| 
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|     template< class StateIn >
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|     bool resize_impl( const StateIn &x )
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|     {
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|         bool resized( false );
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|         resized |= adjust_size_by_resizeability( m_x_tmp , x , typename is_resizeable<state_type>::type() );
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|         for( size_t i = 0 ; i < StageCount-1 ; ++i )
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|         {
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|             resized |= adjust_size_by_resizeability( m_F[i] , x , typename is_resizeable<deriv_type>::type() );
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|         }
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|         return resized;
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|     }
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| 
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| 
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|     rk_algorithm_type m_rk_algorithm;
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| 
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|     resizer_type m_resizer;
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| 
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|     wrapped_state_type m_x_tmp;
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|     wrapped_deriv_type m_F[StageCount-1];
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| 
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| };
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| 
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| 
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| 
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| /*********** DOXYGEN *************/
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| 
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| /**
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|  * \class explicit_generic_rk
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|  * \brief A generic implementation of explicit Runge-Kutta algorithms. This class is as a base class
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|  * for all explicit Runge-Kutta steppers.
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|  *
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|  * This class implements the explicit Runge-Kutta algorithms without error estimation in a generic way.
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|  * The Butcher tableau is passed to the stepper which constructs the stepper scheme with the help of a
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|  * template-metaprogramming algorithm. ToDo : Add example!
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|  * 
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|  * This class derives explicit_stepper_base which provides the stepper interface.
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|  *
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|  * \tparam StageCount The number of stages of the Runge-Kutta algorithm.
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|  * \tparam Order The order of the stepper.
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|  * \tparam State The type representing the state of the ODE.
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|  * \tparam Value The floating point type which is used in the computations.
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|  * \tparam Time The type representing the independent variable - the time - of the ODE.
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|  * \tparam Algebra The algebra type.
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|  * \tparam Operations The operations type.
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|  * \tparam Resizer The resizer policy type.
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|  */
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| 
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|     /**
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|      * \fn explicit_generic_rk::explicit_generic_rk( const coef_a_type &a , const coef_b_type &b , const coef_c_type &c , const algebra_type &algebra )
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|      * \brief Constructs the explicit_generic_rk class. See examples section for details on the coefficients.
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|      * \param a Triangular matrix of parameters b in the Butcher tableau.
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|      * \param b Last row of the butcher tableau.
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|      * \param c Parameters to calculate the time points in the Butcher tableau.
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|      * \param algebra A copy of algebra is made and stored inside explicit_stepper_base.
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|      */
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|     
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|     /**
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|      * \fn explicit_generic_rk::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt , time_type t , StateOut &out , time_type dt )
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|      * \brief This method performs one step. The derivative `dxdt` of `in` at the time `t` is passed to the method.
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|      * The result is updated out of place, hence the input is in `in` and the output in `out`.
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|      * Access to this step functionality is provided by explicit_stepper_base and 
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|      * `do_step_impl` should not be called directly.
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|      *
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|      * \param system The system function to solve, hence the r.h.s. of the ODE. It must fulfill the
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|      *               Simple System concept.
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|      * \param in The state of the ODE which should be solved. in is not modified in this method
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|      * \param dxdt The derivative of x at t.
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|      * \param t The value of the time, at which the step should be performed.
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|      * \param out The result of the step is written in out.
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|      * \param dt The step size.
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|      */
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| 
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| 
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|     /**
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|      * \fn explicit_generic_rk::adjust_size( const StateIn &x )
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|      * \brief Adjust the size of all temporaries in the stepper manually.
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|      * \param x A state from which the size of the temporaries to be resized is deduced.
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|      */
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| 
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| }
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| }
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| }
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| #endif // BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_GENERIC_RK_HPP_INCLUDED
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