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- /*
- [auto_generated]
- boost/numeric/odeint/integrate/detail/integrate_adaptive.hpp
- [begin_description]
- Default Integrate adaptive implementation.
- [end_description]
- Copyright 2009-2011 Karsten Ahnert
- Copyright 2009-2011 Mario Mulansky
- 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_INTEGRATE_DETAIL_INTEGRATE_ADAPTIVE_HPP_INCLUDED
- #define BOOST_NUMERIC_ODEINT_INTEGRATE_DETAIL_INTEGRATE_ADAPTIVE_HPP_INCLUDED
- #include <stdexcept>
- #include <boost/numeric/odeint/stepper/stepper_categories.hpp>
- #include <boost/numeric/odeint/stepper/controlled_step_result.hpp>
- #include <boost/numeric/odeint/integrate/detail/integrate_n_steps.hpp>
- #include <boost/numeric/odeint/util/bind.hpp>
- #include <boost/numeric/odeint/util/unwrap_reference.hpp>
- #include <boost/numeric/odeint/util/copy.hpp>
- #include <boost/numeric/odeint/util/detail/less_with_sign.hpp>
- #include <iostream>
- namespace boost {
- namespace numeric {
- namespace odeint {
- namespace detail {
- // forward declaration
- template< class Stepper , class System , class State , class Time , class Observer>
- Time integrate_n_steps(
- Stepper stepper , System system , State &start_state ,
- Time start_time , Time dt , size_t num_of_steps ,
- Observer observer , stepper_tag );
- /*
- * integrate_adaptive for simple stepper is basically an integrate_const + some last step
- */
- template< class Stepper , class System , class State , class Time , class Observer >
- size_t integrate_adaptive(
- Stepper stepper , System system , State &start_state ,
- Time start_time , Time end_time , Time dt ,
- Observer observer , stepper_tag
- )
- {
- size_t steps = static_cast< size_t >( (end_time-start_time)/dt );
- Time end = detail::integrate_n_steps( stepper , system , start_state , start_time ,
- dt , steps , observer , stepper_tag() );
- if( less_with_sign( end , end_time , dt ) )
- { //make a last step to end exactly at end_time
- stepper.do_step( system , start_state , end , end_time - end );
- steps++;
- typename odeint::unwrap_reference< Observer >::type &obs = observer;
- obs( start_state , end_time );
- }
- return steps;
- }
- /*
- * classical integrate adaptive
- */
- template< class Stepper , class System , class State , class Time , class Observer >
- size_t integrate_adaptive(
- Stepper stepper , System system , State &start_state ,
- Time &start_time , Time end_time , Time &dt ,
- Observer observer , controlled_stepper_tag
- )
- {
- typename odeint::unwrap_reference< Observer >::type &obs = observer;
- const size_t max_attempts = 1000;
- const char *error_string = "Integrate adaptive : Maximal number of iterations reached. A step size could not be found.";
- size_t count = 0;
- while( less_with_sign( start_time , end_time , dt ) )
- {
- obs( start_state , start_time );
- if( less_with_sign( end_time , start_time + dt , dt ) )
- {
- dt = end_time - start_time;
- }
- size_t trials = 0;
- controlled_step_result res = success;
- do
- {
- res = stepper.try_step( system , start_state , start_time , dt );
- ++trials;
- }
- while( ( res == fail ) && ( trials < max_attempts ) );
- if( trials == max_attempts ) throw std::overflow_error( error_string );
- ++count;
- }
- obs( start_state , start_time );
- return count;
- }
- /*
- * integrate adaptive for dense output steppers
- *
- * step size control is used if the stepper supports it
- */
- template< class Stepper , class System , class State , class Time , class Observer >
- size_t integrate_adaptive(
- Stepper stepper , System system , State &start_state ,
- Time start_time , Time end_time , Time dt ,
- Observer observer , dense_output_stepper_tag )
- {
- typename odeint::unwrap_reference< Observer >::type &obs = observer;
- size_t count = 0;
- stepper.initialize( start_state , start_time , dt );
- while( less_with_sign( stepper.current_time() , end_time , stepper.current_time_step() ) )
- {
- while( less_eq_with_sign( stepper.current_time() + stepper.current_time_step() ,
- end_time ,
- stepper.current_time_step() ) )
- { //make sure we don't go beyond the end_time
- obs( stepper.current_state() , stepper.current_time() );
- stepper.do_step( system );
- ++count;
- }
- stepper.initialize( stepper.current_state() , stepper.current_time() , end_time - stepper.current_time() );
- }
- obs( stepper.current_state() , stepper.current_time() );
- // overwrite start_state with the final point
- boost::numeric::odeint::copy( stepper.current_state() , start_state );
- return count;
- }
- } // namespace detail
- } // namespace odeint
- } // namespace numeric
- } // namespace boost
- #endif // BOOST_NUMERIC_ODEINT_INTEGRATE_DETAIL_INTEGRATE_ADAPTIVE_HPP_INCLUDED
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