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/*
[auto_generated]
boost/numeric/odeint/iterator/detail/adaptive_iterator_impl.hpp
[begin_description]
tba.
[end_description]
Copyright 2009-2012 Karsten Ahnert
Copyright 2009-2012 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_ITERATOR_DETAIL_ADAPTIVE_ITERATOR_IMPL_HPP_DEFINED
#define BOOST_NUMERIC_ODEINT_ITERATOR_DETAIL_ADAPTIVE_ITERATOR_IMPL_HPP_DEFINED
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/throw_exception.hpp>
#include <boost/numeric/odeint/util/unit_helper.hpp>
#include <boost/numeric/odeint/util/copy.hpp>
#include <boost/numeric/odeint/stepper/controlled_step_result.hpp>
#include <boost/numeric/odeint/iterator/detail/ode_iterator_base.hpp>
namespace boost {
namespace numeric {
namespace odeint {
template< class Iterator , class Stepper , class System , class State , typename Tag , typename StepperTag >
class adaptive_iterator_impl;
/*
* Specilization for controlled steppers
*/
/**
* \brief ODE Iterator with adaptive step size control. The value type of this iterator is the state type of the stepper.
*
* Implements an ODE iterator with adaptive step size control. Uses controlled steppers. adaptive_iterator is a model
* of single-pass iterator.
*
* The value type of this iterator is the state type of the stepper. Hence one can only access the state and not the current time.
*
* \tparam Stepper The stepper type which should be used during the iteration.
* \tparam System The type of the system function (ODE) which should be solved.
*/
template< class Iterator , class Stepper , class System , class State , typename Tag >
class adaptive_iterator_impl< Iterator , Stepper , System , State , Tag , controlled_stepper_tag >
: public detail::ode_iterator_base< Iterator , Stepper , System , State , Tag >
{
private:
typedef Stepper stepper_type;
typedef System system_type;
typedef typename boost::numeric::odeint::unwrap_reference< stepper_type >::type unwrapped_stepper_type;
typedef State state_type;
typedef typename traits::time_type< stepper_type >::type time_type;
typedef typename traits::value_type< stepper_type >::type ode_value_type;
#ifndef DOXYGEN_SKIP
typedef detail::ode_iterator_base< Iterator , Stepper , System , State , Tag > base_type;
#endif
public:
/**
* \brief Constructs an adaptive_iterator. This constructor should be used to construct the begin iterator.
*
* \param stepper The stepper to use during the iteration.
* \param sys The system function (ODE) to solve.
* \param s The initial state. adaptive_iterator stores a reference of s and changes its value during the iteration.
* \param t The initial time.
* \param t_end The end time, at which the iteration should stop.
* \param dt The initial time step.
*/
adaptive_iterator_impl( stepper_type stepper , system_type sys , state_type &s , time_type t , time_type t_end , time_type dt )
: base_type( stepper , sys , t , dt ) , m_t_end( t_end ) , m_state( &s )
{
if( detail::less_with_sign( this->m_t_end , this->m_t , this->m_dt ) )
this->m_at_end = true;
}
/**
* \brief Constructs an adaptive_iterator. This constructor should be used to construct the end iterator.
*
* \param stepper The stepper to use during the iteration.
* \param sys The system function (ODE) to solve.
* \param s The initial state. adaptive_iterator store a reference of s and changes its value during the iteration.
*/
adaptive_iterator_impl( stepper_type stepper , system_type sys , state_type &s )
: base_type( stepper , sys ) , m_state( &s ) { }
protected:
friend class boost::iterator_core_access;
void increment()
{
if( detail::less_with_sign( this->m_t , this->m_t_end , this->m_dt) )
{
if( detail::less_with_sign( this->m_t_end ,
static_cast<time_type>(this->m_t + this->m_dt) ,
this->m_dt ) )
{
this->m_dt = this->m_t_end - this->m_t;
}
unwrapped_stepper_type &stepper = this->m_stepper;
const size_t max_attempts = 1000;
size_t trials = 0;
controlled_step_result res = success;
do
{
res = stepper.try_step( this->m_system , *( this->m_state ) , this->m_t , this->m_dt );
++trials;
}
while( ( res == fail ) && ( trials < max_attempts ) );
if( trials == max_attempts )
{
BOOST_THROW_EXCEPTION( std::overflow_error( "Adaptive iterator : Maximal number of iterations reached. A step size could not be found." ));
}
} else {
this->m_at_end = true;
}
}
public:
const state_type& get_state() const
{
return *this->m_state;
}
private:
time_type m_t_end;
state_type* m_state;
};
/*
* Specilization for dense outputer steppers
*/
/**
* \brief ODE Iterator with adaptive step size control. The value type of this iterator is the state type of the stepper.
*
* Implements an ODE iterator with adaptive step size control. Uses dense-output steppers. adaptive_iterator is a model
* of single-pass iterator.
*
* The value type of this iterator is the state type of the stepper. Hence one can only access the state and not the current time.
*
* \tparam Stepper The stepper type which should be used during the iteration.
* \tparam System The type of the system function (ODE) which should be solved.
*/
template< class Iterator , class Stepper , class System , class State , typename Tag >
class adaptive_iterator_impl< Iterator , Stepper , System , State , Tag , dense_output_stepper_tag >
: public detail::ode_iterator_base< Iterator , Stepper , System , State , Tag >
{
private:
typedef Stepper stepper_type;
typedef System system_type;
typedef typename boost::numeric::odeint::unwrap_reference< stepper_type >::type unwrapped_stepper_type;
typedef State state_type;
typedef typename traits::time_type< stepper_type >::type time_type;
typedef typename traits::value_type< stepper_type >::type ode_value_type;
#ifndef DOXYGEN_SKIP
typedef detail::ode_iterator_base< Iterator , Stepper , System , State , Tag > base_type;
#endif
public:
/**
* \brief Constructs an adaptive_iterator. This constructor should be used to construct the begin iterator.
*
* \param stepper The stepper to use during the iteration.
* \param sys The system function (ODE) to solve.
* \param s The initial state.
* \param t The initial time.
* \param t_end The end time, at which the iteration should stop.
* \param dt The initial time step.
*/
adaptive_iterator_impl( stepper_type stepper , system_type sys , state_type &s , time_type t , time_type t_end , time_type dt )
: base_type( stepper , sys , t , dt ) , m_t_end( t_end )
{
if( detail::less_eq_with_sign( this->m_t , this->m_t_end , this->m_dt ) )
{
unwrapped_stepper_type &st = this->m_stepper;
st.initialize( s , this->m_t , this->m_dt );
} else {
this->m_at_end = true;
}
}
/**
* \brief Constructs an adaptive_iterator. This constructor should be used to construct the end iterator.
*
* \param stepper The stepper to use during the iteration.
* \param sys The system function (ODE) to solve.
* \param s The initial state.
*/
adaptive_iterator_impl( stepper_type stepper , system_type sys , state_type& /* s */ )
: base_type( stepper , sys ) { }
protected:
friend class boost::iterator_core_access;
void increment()
{
unwrapped_stepper_type &stepper = this->m_stepper;
if( detail::less_with_sign( this->m_t ,
this->m_t_end ,
stepper.current_time_step() ) )
{
if( detail::less_with_sign( this->m_t_end ,
static_cast<time_type>(this->m_t + stepper.current_time_step()) ,
stepper.current_time_step() ) )
{
// make stpper to end exactly at t_end
stepper.initialize( stepper.current_state() , stepper.current_time() ,
static_cast<time_type>(this->m_t_end-this->m_t) );
}
stepper.do_step( this->m_system );
this->m_t = stepper.current_time();
} else { // we have reached t_end
this->m_at_end = true;
}
}
public:
const state_type& get_state() const
{
const unwrapped_stepper_type &stepper = this->m_stepper;
return stepper.current_state();
}
private:
time_type m_t_end;
};
} // namespace odeint
} // namespace numeric
} // namespace boost
#endif // BOOST_NUMERIC_ODEINT_ITERATOR_DETAIL_ADAPTIVE_ITERATOR_IMPL_HPP_DEFINED
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