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			12 KiB
		
	
	
	
		
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			304 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| /*
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|  [auto_generated]
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|  boost/numeric/odeint/stepper/adams_bashforth_moulton.hpp
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| 
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|  [begin_description]
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|  Implementation of the Adams-Bashforth-Moulton method, a predictor-corrector multistep method.
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|  [end_description]
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| 
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|  Copyright 2011-2013 Karsten Ahnert
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|  Copyright 2011-2013 Mario Mulansky
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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_ADAMS_BASHFORTH_MOULTON_HPP_INCLUDED
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| #define BOOST_NUMERIC_ODEINT_STEPPER_ADAMS_BASHFORTH_MOULTON_HPP_INCLUDED
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| 
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| 
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| #include <boost/numeric/odeint/util/bind.hpp>
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| 
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| #include <boost/numeric/odeint/stepper/stepper_categories.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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| 
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| #include <boost/numeric/odeint/util/state_wrapper.hpp>
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| #include <boost/numeric/odeint/util/resizer.hpp>
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| 
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| #include <boost/numeric/odeint/stepper/adams_bashforth.hpp>
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| #include <boost/numeric/odeint/stepper/adams_moulton.hpp>
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| 
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| 
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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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| 
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| template<
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| size_t Steps ,
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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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| class InitializingStepper = runge_kutta4< State , Value , Deriv , Time , Algebra , Operations, Resizer >
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| >
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| class adams_bashforth_moulton
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| {
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| 
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| #ifndef DOXYGEN_SKIP
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|     BOOST_STATIC_ASSERT(( Steps > 0 ));
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|     BOOST_STATIC_ASSERT(( Steps < 9 ));
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| #endif
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| 
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| public :
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| 
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|     typedef State state_type;
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|     typedef state_wrapper< state_type > wrapped_state_type;
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|     typedef Value value_type;
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|     typedef Deriv deriv_type;
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|     typedef state_wrapper< deriv_type > wrapped_deriv_type;
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|     typedef Time time_type;
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|     typedef Algebra algebra_type;
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|     typedef Operations operations_type;
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|     typedef Resizer resizer_type;
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|     typedef stepper_tag stepper_category;
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|     typedef InitializingStepper initializing_stepper_type;
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| 
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|     static const size_t steps = Steps;
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| #ifndef DOXYGEN_SKIP
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|     typedef adams_bashforth< steps , state_type , value_type , deriv_type , time_type , algebra_type , operations_type , resizer_type, initializing_stepper_type > adams_bashforth_type;
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|     typedef adams_moulton< steps , state_type , value_type , deriv_type , time_type , algebra_type , operations_type , resizer_type > adams_moulton_type;
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|     typedef adams_bashforth_moulton< steps , state_type , value_type , deriv_type , time_type , algebra_type , operations_type , resizer_type , initializing_stepper_type> stepper_type;
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| #endif //DOXYGEN_SKIP
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|     typedef unsigned short order_type;
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|     static const order_type order_value = steps;
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| 
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|     /** \brief Constructs the adams_bashforth class. */
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|     adams_bashforth_moulton( void )
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|     : m_adams_bashforth() , m_adams_moulton( m_adams_bashforth.algebra() )
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|     , m_x() , m_resizer()
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|     { }
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| 
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|     adams_bashforth_moulton( const algebra_type &algebra )
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|     : m_adams_bashforth( algebra ) , m_adams_moulton( m_adams_bashforth.algebra() )
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|     , m_x() , m_resizer()    
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|     { }
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| 
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|     order_type order( void ) const { return order_value; }
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| 
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|     template< class System , class StateInOut >
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|     void do_step( System system , StateInOut &x , time_type t , time_type dt )
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|     {
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|         do_step_impl1( system , x , t , dt );
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|     }
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| 
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|     /**
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|      * \brief Second version to solve the forwarding problem, can be called with Boost.Range as StateInOut.
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|      */
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|     template< class System , class StateInOut >
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|     void do_step( System system , const StateInOut &x , time_type t , time_type dt )
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|     {
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|         do_step_impl1( system , x , t , dt );
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|     }
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| 
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|     template< class System , class StateIn , class StateOut >
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|     void do_step( System system , const StateIn &in , time_type t , const StateOut &out , time_type dt )
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|     {
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|         do_step_impl2( system , in , t , out , dt );
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|     }
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| 
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|     /**
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|      * \brief Second version to solve the forwarding problem, can be called with Boost.Range as StateOut.
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|      */
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|     template< class System , class StateIn , class StateOut >
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|     void do_step( System system , const StateIn &in , time_type t , StateOut &out , time_type dt )
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|     {
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|         do_step_impl2( system , in ,t , out , dt );
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|     }
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| 
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| 
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|     template< class StateType >
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|     void adjust_size( const StateType &x )
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|     {
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|         m_adams_bashforth.adjust_size( x );
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|         m_adams_moulton.adjust_size( x );
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|         resize_impl( x );
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|     }
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| 
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| 
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|     template< class ExplicitStepper , class System , class StateIn >
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|     void initialize( ExplicitStepper explicit_stepper , System system , StateIn &x , time_type &t , time_type dt )
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|     {
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|         m_adams_bashforth.initialize( explicit_stepper , system , x , t , dt );
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|     }
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| 
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| 
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|     template< class System , class StateIn >
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|     void initialize( System system , StateIn &x , time_type &t , time_type dt )
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|     {
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|         m_adams_bashforth.initialize( system , x , t , dt );
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|     }
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| 
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| 
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| 
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| private:
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|     
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|     template< typename System , typename StateInOut >
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|     void do_step_impl1( System system , StateInOut &x , time_type t , time_type dt )
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|     {
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|         if( m_adams_bashforth.is_initialized() )
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|         {
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|             m_resizer.adjust_size( x , detail::bind( &stepper_type::template resize_impl< StateInOut > , detail::ref( *this ) , detail::_1 ) );
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|             m_adams_bashforth.do_step( system , x , t , m_x.m_v , dt );
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|             m_adams_moulton.do_step( system , x , m_x.m_v , t+dt , x , dt , m_adams_bashforth.step_storage() );
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|         }
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|         else
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|         {
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|             m_adams_bashforth.do_step( system , x , t , dt );
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|         }
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|     }
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|     
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|     template< typename System , typename StateIn , typename StateInOut >
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|     void do_step_impl2( System system , StateIn const &in , time_type t , StateInOut & out , time_type dt )
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|     {
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|         if( m_adams_bashforth.is_initialized() )
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|         {
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|             m_resizer.adjust_size( in , detail::bind( &stepper_type::template resize_impl< StateInOut > , detail::ref( *this ) , detail::_1 ) );        
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|             m_adams_bashforth.do_step( system , in , t , m_x.m_v , dt );
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|             m_adams_moulton.do_step( system , in , m_x.m_v , t , out , dt , m_adams_bashforth.step_storage() );
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|         }
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|         else
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|         {
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|             m_adams_bashforth.do_step( system , in , t , out , dt );
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|         }
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|     }
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| 
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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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|         return adjust_size_by_resizeability( m_x , x , typename is_resizeable< state_type >::type() );
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|     }
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| 
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|     adams_bashforth_type m_adams_bashforth;
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|     adams_moulton_type m_adams_moulton;
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|     wrapped_state_type m_x;
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|     resizer_type m_resizer;
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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 adams_bashforth_moulton
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|  * \brief The Adams-Bashforth-Moulton multistep algorithm.
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|  *
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|  * The Adams-Bashforth method is a multi-step predictor-corrector algorithm 
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|  * with configurable step number. The step number is specified as template 
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|  * parameter Steps and it then uses the result from the previous Steps steps. 
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|  * See also
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|  * <a href="http://en.wikipedia.org/wiki/Linear_multistep_method">en.wikipedia.org/wiki/Linear_multistep_method</a>.
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|  * Currently, a maximum of Steps=8 is supported.
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|  * The method is explicit and fulfills the Stepper concept. Step size control
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|  * or continuous output are not provided.
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|  * 
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|  * This class derives from algebra_base and inherits its interface via
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|  * CRTP (current recurring template pattern). For more details see
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|  * algebra_stepper_base.
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|  *
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|  * \tparam Steps The number of steps (maximal 8).
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|  * \tparam State The state type.
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|  * \tparam Value The value type.
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|  * \tparam Deriv The type representing the time derivative of the state.
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|  * \tparam Time The time representing the independent variable - the time.
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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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|  * \tparam InitializingStepper The stepper for the first two steps.
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|  */
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| 
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|     /**
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|      * \fn adams_bashforth_moulton::adams_bashforth_moulton( const algebra_type &algebra )
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|      * \brief Constructs the adams_bashforth class. This constructor can be used as a default
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|      * constructor if the algebra has a default constructor. 
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|      * \param algebra A copy of algebra is made and stored.
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|      */
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| 
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|     /**
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|      * \fn adams_bashforth_moulton::order( void ) const
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|      * \brief Returns the order of the algorithm, which is equal to the number of steps+1.
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|      * \return order of the method.
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|      */
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| 
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|     /**
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|      * \fn adams_bashforth_moulton::do_step( System system , StateInOut &x , time_type t , time_type dt )
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|      * \brief This method performs one step. It transforms the result in-place.
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|      *
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|      * \param system The system function to solve, hence the r.h.s. of the ordinary differential equation. It must fulfill the
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|      *               Simple System concept.
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|      * \param x The state of the ODE which should be solved. After calling do_step the result is updated in x.
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|      * \param t The value of the time, at which the step should be performed.
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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 adams_bashforth_moulton::do_step( System system , const StateIn &in , time_type t , const StateOut &out , time_type dt )
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|      * \brief The method performs one step with the stepper passed by Stepper. The state of the ODE is updated out-of-place.
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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 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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|      * \fn adams_bashforth_moulton::adjust_size( const StateType &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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|      * \fn adams_bashforth_moulton::initialize( ExplicitStepper explicit_stepper , System system , StateIn &x , time_type &t , time_type dt )
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|      * \brief Initialized the stepper. Does Steps-1 steps with the explicit_stepper to fill the buffer.
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|      * \note The state x and time t are updated to the values after Steps-1 initial steps.
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|      * \param explicit_stepper the stepper used to fill the buffer of previous step results
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|      * \param system The system function to solve, hence the r.h.s. of the ordinary differential equation. It must fulfill the
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|      *               Simple System concept.
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|      * \param x The initial state of the ODE which should be solved, updated after in this method.
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|      * \param t The initial time, updated in this method.
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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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|      * \fn adams_bashforth_moulton::initialize( System system , StateIn &x , time_type &t , time_type dt )
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|      * \brief Initialized the stepper. Does Steps-1 steps using the standard initializing stepper 
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|      * of the underlying adams_bashforth stepper.
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|      * \param system The system function to solve, hence the r.h.s. of the ordinary differential equation. It must fulfill the
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|      *               Simple System concept.
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|      * \param x The state of the ODE which should be solved. After calling do_step the result is updated in x.
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|      * \param t The value of the time, at which the step should be performed.
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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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| } // odeint
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| } // numeric
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| } // boost
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| 
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| 
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| 
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| #endif // BOOST_NUMERIC_ODEINT_STEPPER_ADAMS_BASHFORTH_MOULTON_HPP_INCLUDED
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