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+/*
+ [auto_generated]
+ boost/numeric/odeint/stepper/runge_kutta_dopri5.hpp
+
+ [begin_description]
+ Implementation of the Dormand-Prince 5(4) method. This stepper can also be used with the dense-output controlled stepper.
+ [end_description]
+
+ Copyright 2010-2013 Karsten Ahnert
+ Copyright 2010-2013 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_RUNGE_KUTTA_DOPRI5_HPP_INCLUDED
+#define BOOST_NUMERIC_ODEINT_STEPPER_RUNGE_KUTTA_DOPRI5_HPP_INCLUDED
+
+
+#include <boost/numeric/odeint/util/bind.hpp>
+
+#include <boost/numeric/odeint/stepper/base/explicit_error_stepper_fsal_base.hpp>
+#include <boost/numeric/odeint/algebra/range_algebra.hpp>
+#include <boost/numeric/odeint/algebra/default_operations.hpp>
+#include <boost/numeric/odeint/algebra/algebra_dispatcher.hpp>
+#include <boost/numeric/odeint/algebra/operations_dispatcher.hpp>
+#include <boost/numeric/odeint/stepper/stepper_categories.hpp>
+
+#include <boost/numeric/odeint/util/state_wrapper.hpp>
+#include <boost/numeric/odeint/util/is_resizeable.hpp>
+#include <boost/numeric/odeint/util/resizer.hpp>
+#include <boost/numeric/odeint/util/same_instance.hpp>
+
+namespace boost {
+namespace numeric {
+namespace odeint {
+
+
+
+template<
+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 runge_kutta_dopri5
+#ifndef DOXYGEN_SKIP
+: public explicit_error_stepper_fsal_base<
+ runge_kutta_dopri5< State , Value , Deriv , Time , Algebra , Operations , Resizer > ,
+ 5 , 5 , 4 , State , Value , Deriv , Time , Algebra , Operations , Resizer >
+#else
+: public explicit_error_stepper_fsal_base
+#endif
+{
+
+public :
+
+ #ifndef DOXYGEN_SKIP
+ typedef explicit_error_stepper_fsal_base<
+ runge_kutta_dopri5< State , Value , Deriv , Time , Algebra , Operations , Resizer > ,
+ 5 , 5 , 4 , State , Value , Deriv , Time , Algebra , Operations , Resizer > stepper_base_type;
+ #else
+ typedef explicit_error_stepper_fsal_base< runge_kutta_dopri5< ... > , ... > stepper_base_type;
+ #endif
+
+ typedef typename stepper_base_type::state_type state_type;
+ typedef typename stepper_base_type::value_type value_type;
+ typedef typename stepper_base_type::deriv_type deriv_type;
+ typedef typename stepper_base_type::time_type time_type;
+ typedef typename stepper_base_type::algebra_type algebra_type;
+ typedef typename stepper_base_type::operations_type operations_type;
+ typedef typename stepper_base_type::resizer_type resizer_type;
+
+ #ifndef DOXYGEN_SKIP
+ typedef typename stepper_base_type::stepper_type stepper_type;
+ typedef typename stepper_base_type::wrapped_state_type wrapped_state_type;
+ typedef typename stepper_base_type::wrapped_deriv_type wrapped_deriv_type;
+ #endif // DOXYGEN_SKIP
+
+
+ runge_kutta_dopri5( const algebra_type &algebra = algebra_type() ) : stepper_base_type( algebra )
+ { }
+
+
+ template< class System , class StateIn , class DerivIn , class StateOut , class DerivOut >
+ void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt_in , time_type t ,
+ StateOut &out , DerivOut &dxdt_out , time_type dt )
+ {
+ const value_type a2 = static_cast<value_type> ( 1 ) / static_cast<value_type>( 5 );
+ const value_type a3 = static_cast<value_type> ( 3 ) / static_cast<value_type> ( 10 );
+ const value_type a4 = static_cast<value_type> ( 4 ) / static_cast<value_type> ( 5 );
+ const value_type a5 = static_cast<value_type> ( 8 )/static_cast<value_type> ( 9 );
+
+ const value_type b21 = static_cast<value_type> ( 1 ) / static_cast<value_type> ( 5 );
+
+ const value_type b31 = static_cast<value_type> ( 3 ) / static_cast<value_type>( 40 );
+ const value_type b32 = static_cast<value_type> ( 9 ) / static_cast<value_type>( 40 );
+
+ const value_type b41 = static_cast<value_type> ( 44 ) / static_cast<value_type> ( 45 );
+ const value_type b42 = static_cast<value_type> ( -56 ) / static_cast<value_type> ( 15 );
+ const value_type b43 = static_cast<value_type> ( 32 ) / static_cast<value_type> ( 9 );
+
+ const value_type b51 = static_cast<value_type> ( 19372 ) / static_cast<value_type>( 6561 );
+ const value_type b52 = static_cast<value_type> ( -25360 ) / static_cast<value_type> ( 2187 );
+ const value_type b53 = static_cast<value_type> ( 64448 ) / static_cast<value_type>( 6561 );
+ const value_type b54 = static_cast<value_type> ( -212 ) / static_cast<value_type>( 729 );
+
+ const value_type b61 = static_cast<value_type> ( 9017 ) / static_cast<value_type>( 3168 );
+ const value_type b62 = static_cast<value_type> ( -355 ) / static_cast<value_type>( 33 );
+ const value_type b63 = static_cast<value_type> ( 46732 ) / static_cast<value_type>( 5247 );
+ const value_type b64 = static_cast<value_type> ( 49 ) / static_cast<value_type>( 176 );
+ const value_type b65 = static_cast<value_type> ( -5103 ) / static_cast<value_type>( 18656 );
+
+ const value_type c1 = static_cast<value_type> ( 35 ) / static_cast<value_type>( 384 );
+ const value_type c3 = static_cast<value_type> ( 500 ) / static_cast<value_type>( 1113 );
+ const value_type c4 = static_cast<value_type> ( 125 ) / static_cast<value_type>( 192 );
+ const value_type c5 = static_cast<value_type> ( -2187 ) / static_cast<value_type>( 6784 );
+ const value_type c6 = static_cast<value_type> ( 11 ) / static_cast<value_type>( 84 );
+
+ typename odeint::unwrap_reference< System >::type &sys = system;
+
+ m_k_x_tmp_resizer.adjust_size( in , detail::bind( &stepper_type::template resize_k_x_tmp_impl<StateIn> , detail::ref( *this ) , detail::_1 ) );
+
+ //m_x_tmp = x + dt*b21*dxdt
+ stepper_base_type::m_algebra.for_each3( m_x_tmp.m_v , in , dxdt_in ,
+ typename operations_type::template scale_sum2< value_type , time_type >( 1.0 , dt*b21 ) );
+
+ sys( m_x_tmp.m_v , m_k2.m_v , t + dt*a2 );
+ // m_x_tmp = x + dt*b31*dxdt + dt*b32*m_k2
+ stepper_base_type::m_algebra.for_each4( m_x_tmp.m_v , in , dxdt_in , m_k2.m_v ,
+ typename operations_type::template scale_sum3< value_type , time_type , time_type >( 1.0 , dt*b31 , dt*b32 ));
+
+ sys( m_x_tmp.m_v , m_k3.m_v , t + dt*a3 );
+ // m_x_tmp = x + dt * (b41*dxdt + b42*m_k2 + b43*m_k3)
+ stepper_base_type::m_algebra.for_each5( m_x_tmp.m_v , in , dxdt_in , m_k2.m_v , m_k3.m_v ,
+ typename operations_type::template scale_sum4< value_type , time_type , time_type , time_type >( 1.0 , dt*b41 , dt*b42 , dt*b43 ));
+
+ sys( m_x_tmp.m_v, m_k4.m_v , t + dt*a4 );
+ stepper_base_type::m_algebra.for_each6( m_x_tmp.m_v , in , dxdt_in , m_k2.m_v , m_k3.m_v , m_k4.m_v ,
+ typename operations_type::template scale_sum5< value_type , time_type , time_type , time_type , time_type >( 1.0 , dt*b51 , dt*b52 , dt*b53 , dt*b54 ));
+
+ sys( m_x_tmp.m_v , m_k5.m_v , t + dt*a5 );
+ stepper_base_type::m_algebra.for_each7( m_x_tmp.m_v , in , dxdt_in , m_k2.m_v , m_k3.m_v , m_k4.m_v , m_k5.m_v ,
+ typename operations_type::template scale_sum6< value_type , time_type , time_type , time_type , time_type , time_type >( 1.0 , dt*b61 , dt*b62 , dt*b63 , dt*b64 , dt*b65 ));
+
+ sys( m_x_tmp.m_v , m_k6.m_v , t + dt );
+ stepper_base_type::m_algebra.for_each7( out , in , dxdt_in , m_k3.m_v , m_k4.m_v , m_k5.m_v , m_k6.m_v ,
+ typename operations_type::template scale_sum6< value_type , time_type , time_type , time_type , time_type , time_type >( 1.0 , dt*c1 , dt*c3 , dt*c4 , dt*c5 , dt*c6 ));
+
+ // the new derivative
+ sys( out , dxdt_out , t + dt );
+ }
+
+
+
+ template< class System , class StateIn , class DerivIn , class StateOut , class DerivOut , class Err >
+ void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt_in , time_type t ,
+ StateOut &out , DerivOut &dxdt_out , time_type dt , Err &xerr )
+ {
+ const value_type c1 = static_cast<value_type> ( 35 ) / static_cast<value_type>( 384 );
+ const value_type c3 = static_cast<value_type> ( 500 ) / static_cast<value_type>( 1113 );
+ const value_type c4 = static_cast<value_type> ( 125 ) / static_cast<value_type>( 192 );
+ const value_type c5 = static_cast<value_type> ( -2187 ) / static_cast<value_type>( 6784 );
+ const value_type c6 = static_cast<value_type> ( 11 ) / static_cast<value_type>( 84 );
+
+ const value_type dc1 = c1 - static_cast<value_type> ( 5179 ) / static_cast<value_type>( 57600 );
+ const value_type dc3 = c3 - static_cast<value_type> ( 7571 ) / static_cast<value_type>( 16695 );
+ const value_type dc4 = c4 - static_cast<value_type> ( 393 ) / static_cast<value_type>( 640 );
+ const value_type dc5 = c5 - static_cast<value_type> ( -92097 ) / static_cast<value_type>( 339200 );
+ const value_type dc6 = c6 - static_cast<value_type> ( 187 ) / static_cast<value_type>( 2100 );
+ const value_type dc7 = static_cast<value_type>( -1 ) / static_cast<value_type> ( 40 );
+
+ /* ToDo: copy only if &dxdt_in == &dxdt_out ? */
+ if( same_instance( dxdt_in , dxdt_out ) )
+ {
+ m_dxdt_tmp_resizer.adjust_size( in , detail::bind( &stepper_type::template resize_dxdt_tmp_impl<StateIn> , detail::ref( *this ) , detail::_1 ) );
+ boost::numeric::odeint::copy( dxdt_in , m_dxdt_tmp.m_v );
+ do_step_impl( system , in , dxdt_in , t , out , dxdt_out , dt );
+ //error estimate
+ stepper_base_type::m_algebra.for_each7( xerr , m_dxdt_tmp.m_v , m_k3.m_v , m_k4.m_v , m_k5.m_v , m_k6.m_v , dxdt_out ,
+ typename operations_type::template scale_sum6< time_type , time_type , time_type , time_type , time_type , time_type >( dt*dc1 , dt*dc3 , dt*dc4 , dt*dc5 , dt*dc6 , dt*dc7 ) );
+
+ }
+ else
+ {
+ do_step_impl( system , in , dxdt_in , t , out , dxdt_out , dt );
+ //error estimate
+ stepper_base_type::m_algebra.for_each7( xerr , dxdt_in , m_k3.m_v , m_k4.m_v , m_k5.m_v , m_k6.m_v , dxdt_out ,
+ typename operations_type::template scale_sum6< time_type , time_type , time_type , time_type , time_type , time_type >( dt*dc1 , dt*dc3 , dt*dc4 , dt*dc5 , dt*dc6 , dt*dc7 ) );
+
+ }
+
+ }
+
+
+ /*
+ * Calculates Dense-Output for Dopri5
+ *
+ * See Hairer, Norsett, Wanner: Solving Ordinary Differential Equations, Nonstiff Problems. I, p.191/192
+ *
+ * y(t+theta) = y(t) + h * sum_i^7 b_i(theta) * k_i
+ *
+ * A = theta^2 * ( 3 - 2 theta )
+ * B = theta^2 * ( theta - 1 )
+ * C = theta^2 * ( theta - 1 )^2
+ * D = theta * ( theta - 1 )^2
+ *
+ * b_1( theta ) = A * b_1 - C * X1( theta ) + D
+ * b_2( theta ) = 0
+ * b_3( theta ) = A * b_3 + C * X3( theta )
+ * b_4( theta ) = A * b_4 - C * X4( theta )
+ * b_5( theta ) = A * b_5 + C * X5( theta )
+ * b_6( theta ) = A * b_6 - C * X6( theta )
+ * b_7( theta ) = B + C * X7( theta )
+ *
+ * An alternative Method is described in:
+ *
+ * www-m2.ma.tum.de/homepages/simeon/numerik3/kap3.ps
+ */
+ template< class StateOut , class StateIn1 , class DerivIn1 , class StateIn2 , class DerivIn2 >
+ void calc_state( time_type t , StateOut &x ,
+ const StateIn1 &x_old , const DerivIn1 &deriv_old , time_type t_old ,
+ const StateIn2 & /* x_new */ , const DerivIn2 &deriv_new , time_type t_new ) const
+ {
+ const value_type b1 = static_cast<value_type> ( 35 ) / static_cast<value_type>( 384 );
+ const value_type b3 = static_cast<value_type> ( 500 ) / static_cast<value_type>( 1113 );
+ const value_type b4 = static_cast<value_type> ( 125 ) / static_cast<value_type>( 192 );
+ const value_type b5 = static_cast<value_type> ( -2187 ) / static_cast<value_type>( 6784 );
+ const value_type b6 = static_cast<value_type> ( 11 ) / static_cast<value_type>( 84 );
+
+ const time_type dt = ( t_new - t_old );
+ const value_type theta = ( t - t_old ) / dt;
+ const value_type X1 = static_cast< value_type >( 5 ) * ( static_cast< value_type >( 2558722523LL ) - static_cast< value_type >( 31403016 ) * theta ) / static_cast< value_type >( 11282082432LL );
+ const value_type X3 = static_cast< value_type >( 100 ) * ( static_cast< value_type >( 882725551 ) - static_cast< value_type >( 15701508 ) * theta ) / static_cast< value_type >( 32700410799LL );
+ const value_type X4 = static_cast< value_type >( 25 ) * ( static_cast< value_type >( 443332067 ) - static_cast< value_type >( 31403016 ) * theta ) / static_cast< value_type >( 1880347072LL ) ;
+ const value_type X5 = static_cast< value_type >( 32805 ) * ( static_cast< value_type >( 23143187 ) - static_cast< value_type >( 3489224 ) * theta ) / static_cast< value_type >( 199316789632LL );
+ const value_type X6 = static_cast< value_type >( 55 ) * ( static_cast< value_type >( 29972135 ) - static_cast< value_type >( 7076736 ) * theta ) / static_cast< value_type >( 822651844 );
+ const value_type X7 = static_cast< value_type >( 10 ) * ( static_cast< value_type >( 7414447 ) - static_cast< value_type >( 829305 ) * theta ) / static_cast< value_type >( 29380423 );
+
+ const value_type theta_m_1 = theta - static_cast< value_type >( 1 );
+ const value_type theta_sq = theta * theta;
+ const value_type A = theta_sq * ( static_cast< value_type >( 3 ) - static_cast< value_type >( 2 ) * theta );
+ const value_type B = theta_sq * theta_m_1;
+ const value_type C = theta_sq * theta_m_1 * theta_m_1;
+ const value_type D = theta * theta_m_1 * theta_m_1;
+
+ const value_type b1_theta = A * b1 - C * X1 + D;
+ const value_type b3_theta = A * b3 + C * X3;
+ const value_type b4_theta = A * b4 - C * X4;
+ const value_type b5_theta = A * b5 + C * X5;
+ const value_type b6_theta = A * b6 - C * X6;
+ const value_type b7_theta = B + C * X7;
+
+ // const state_type &k1 = *m_old_deriv;
+ // const state_type &k3 = dopri5().m_k3;
+ // const state_type &k4 = dopri5().m_k4;
+ // const state_type &k5 = dopri5().m_k5;
+ // const state_type &k6 = dopri5().m_k6;
+ // const state_type &k7 = *m_current_deriv;
+
+ stepper_base_type::m_algebra.for_each8( x , x_old , deriv_old , m_k3.m_v , m_k4.m_v , m_k5.m_v , m_k6.m_v , deriv_new ,
+ typename operations_type::template scale_sum7< value_type , time_type , time_type , time_type , time_type , time_type , time_type >( 1.0 , dt * b1_theta , dt * b3_theta , dt * b4_theta , dt * b5_theta , dt * b6_theta , dt * b7_theta ) );
+ }
+
+
+ template< class StateIn >
+ void adjust_size( const StateIn &x )
+ {
+ resize_k_x_tmp_impl( x );
+ resize_dxdt_tmp_impl( x );
+ stepper_base_type::adjust_size( x );
+ }
+
+
+private:
+
+ template< class StateIn >
+ bool resize_k_x_tmp_impl( const StateIn &x )
+ {
+ bool resized = false;
+ resized |= adjust_size_by_resizeability( m_x_tmp , x , typename is_resizeable<state_type>::type() );
+ resized |= adjust_size_by_resizeability( m_k2 , x , typename is_resizeable<deriv_type>::type() );
+ resized |= adjust_size_by_resizeability( m_k3 , x , typename is_resizeable<deriv_type>::type() );
+ resized |= adjust_size_by_resizeability( m_k4 , x , typename is_resizeable<deriv_type>::type() );
+ resized |= adjust_size_by_resizeability( m_k5 , x , typename is_resizeable<deriv_type>::type() );
+ resized |= adjust_size_by_resizeability( m_k6 , x , typename is_resizeable<deriv_type>::type() );
+ return resized;
+ }
+
+ template< class StateIn >
+ bool resize_dxdt_tmp_impl( const StateIn &x )
+ {
+ return adjust_size_by_resizeability( m_dxdt_tmp , x , typename is_resizeable<deriv_type>::type() );
+ }
+
+
+
+ wrapped_state_type m_x_tmp;
+ wrapped_deriv_type m_k2 , m_k3 , m_k4 , m_k5 , m_k6 ;
+ wrapped_deriv_type m_dxdt_tmp;
+ resizer_type m_k_x_tmp_resizer;
+ resizer_type m_dxdt_tmp_resizer;
+};
+
+
+
+/************* DOXYGEN ************/
+/**
+ * \class runge_kutta_dopri5
+ * \brief The Runge-Kutta Dormand-Prince 5 method.
+ *
+ * The Runge-Kutta Dormand-Prince 5 method is a very popular method for solving ODEs, see
+ * <a href=""></a>.
+ * The method is explicit and fulfills the Error Stepper concept. Step size control
+ * is provided but continuous output is available which make this method favourable for many applications.
+ *
+ * This class derives from explicit_error_stepper_fsal_base and inherits its interface via CRTP (current recurring
+ * template pattern). The method possesses the FSAL (first-same-as-last) property. See
+ * explicit_error_stepper_fsal_base for more details.
+ *
+ * \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.
+ */
+
+
+ /**
+ * \fn runge_kutta_dopri5::runge_kutta_dopri5( const algebra_type &algebra )
+ * \brief Constructs the runge_kutta_dopri5 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 inside explicit_stepper_base.
+ */
+
+ /**
+ * \fn runge_kutta_dopri5::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt_in , time_type t , StateOut &out , DerivOut &dxdt_out , time_type dt )
+ * \brief This method performs one step. The derivative `dxdt_in` of `in` at the time `t` is passed to the
+ * method. The result is updated out-of-place, hence the input is in `in` and the output in `out`. Furthermore,
+ * the derivative is update out-of-place, hence the input is assumed to be in `dxdt_in` and the output in
+ * `dxdt_out`.
+ * Access to this step functionality is provided by explicit_error_stepper_fsal_base and
+ * `do_step_impl` should not be called directly.
+ *
+ * \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 dxdt_in The derivative of x at t. dxdt_in is not modified by 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 dxdt_out The result of the new derivative at time t+dt.
+ * \param dt The step size.
+ */
+
+ /**
+ * \fn runge_kutta_dopri5::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt_in , time_type t , StateOut &out , DerivOut &dxdt_out , time_type dt , Err &xerr )
+ * \brief This method performs one step. The derivative `dxdt_in` of `in` at the time `t` is passed to the
+ * method. The result is updated out-of-place, hence the input is in `in` and the output in `out`. Furthermore,
+ * the derivative is update out-of-place, hence the input is assumed to be in `dxdt_in` and the output in
+ * `dxdt_out`.
+ * Access to this step functionality is provided by explicit_error_stepper_fsal_base and
+ * `do_step_impl` should not be called directly.
+ * An estimation of the error is calculated.
+ *
+ * \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 dxdt_in The derivative of x at t. dxdt_in is not modified by 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 dxdt_out The result of the new derivative at time t+dt.
+ * \param dt The step size.
+ * \param xerr An estimation of the error.
+ */
+
+ /**
+ * \fn runge_kutta_dopri5::calc_state( time_type t , StateOut &x , const StateIn1 &x_old , const DerivIn1 &deriv_old , time_type t_old , const StateIn2 & , const DerivIn2 &deriv_new , time_type t_new ) const
+ * \brief This method is used for continuous output and it calculates the state `x` at a time `t` from the
+ * knowledge of two states `old_state` and `current_state` at time points `t_old` and `t_new`. It also uses
+ * internal variables to calculate the result. Hence this method must be called after two successful `do_step`
+ * calls.
+ */
+
+ /**
+ * \fn runge_kutta_dopri5::adjust_size( const StateIn &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.
+ */
+
+} // odeint
+} // numeric
+} // boost
+
+
+#endif // BOOST_NUMERIC_ODEINT_STEPPER_RUNGE_KUTTA_DOPRI5_HPP_INCLUDED