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