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Diffstat (limited to 'boost/numeric/odeint/stepper/symplectic_rkn_sb3a_m4_mclachlan.hpp')
-rw-r--r-- | boost/numeric/odeint/stepper/symplectic_rkn_sb3a_m4_mclachlan.hpp | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/boost/numeric/odeint/stepper/symplectic_rkn_sb3a_m4_mclachlan.hpp b/boost/numeric/odeint/stepper/symplectic_rkn_sb3a_m4_mclachlan.hpp new file mode 100644 index 0000000000..b33773e2f7 --- /dev/null +++ b/boost/numeric/odeint/stepper/symplectic_rkn_sb3a_m4_mclachlan.hpp @@ -0,0 +1,160 @@ +/* + [auto_generated] + boost/numeric/odeint/stepper/symplectic_rkn_sb3a_m4_mclachlan.hpp + + [begin_description] + tba. + [end_description] + + Copyright 2012-2013 Karsten Ahnert + Copyright 2012-2013 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_STEPPER_SYMPLECTIC_RKN_SB3A_M4_MCLACHLAN_HPP_DEFINED +#define BOOST_NUMERIC_ODEINT_STEPPER_SYMPLECTIC_RKN_SB3A_M4_MCLACHLAN_HPP_DEFINED + +#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/util/resizer.hpp> + + +namespace boost { +namespace numeric { +namespace odeint { + +#ifndef DOXYGEN_SKIP +namespace detail { +namespace symplectic_rkn_sb3a_m4_mclachlan { + + /* + exp( a1 t A ) exp( b1 t B ) + exp( a2 t A ) exp( b2 t B ) + exp( a3 t A ) + exp( b2 t B ) exp( a2 t A ) + exp( b1 t B ) exp( a1 t A ) + */ + + + + template< class Value > + struct coef_a_type : public boost::array< Value , 5 > + { + coef_a_type( void ) + { + using std::sqrt; + + Value z = sqrt( static_cast< Value >( 7 ) / static_cast< Value >( 8 ) ) / static_cast< Value >( 3 ); + (*this)[0] = static_cast< Value >( 1 ) / static_cast< Value >( 2 ) - z ; + (*this)[1] = static_cast< Value >( -1 ) / static_cast< Value >( 3 ) + z ; + (*this)[2] = static_cast< Value >( 2 ) / static_cast< Value >( 3 ); + (*this)[3] = (*this)[1]; + (*this)[4] = (*this)[0]; + } + }; + + template< class Value > + struct coef_b_type : public boost::array< Value , 5 > + { + coef_b_type( void ) + { + (*this)[0] = static_cast< Value >( 1 ); + (*this)[1] = static_cast< Value >( -1 ) / static_cast< Value >( 2 ); + (*this)[2] = (*this)[1]; + (*this)[3] = (*this)[0]; + (*this)[4] = static_cast< Value >( 0 ); + } + }; + +} // namespace symplectic_rkn_sb3a_m4_mclachlan +} // namespace detail +#endif // DOXYGEN_SKIP + + + + +template< + class Coor , + class Momentum = Coor , + class Value = double , + class CoorDeriv = Coor , + class MomentumDeriv = Coor , + class Time = Value , + class Algebra = typename algebra_dispatcher< Coor >::algebra_type , + class Operations = typename operations_dispatcher< Coor >::operations_type , + class Resizer = initially_resizer + > +#ifndef DOXYGEN_SKIP +class symplectic_rkn_sb3a_m4_mclachlan : + public symplectic_nystroem_stepper_base +< + 5 , 4 , + Coor , Momentum , Value , CoorDeriv , MomentumDeriv , Time , Algebra , Operations , Resizer + > +#else +class symplectic_rkn_sb3a_m4_mclachlan : public symplectic_nystroem_stepper_base +#endif +{ +public: +#ifndef DOXYGEN_SKIP + typedef symplectic_nystroem_stepper_base + < + 5 , 4 , + Coor , Momentum , Value , CoorDeriv , MomentumDeriv , Time , Algebra , Operations , Resizer + > stepper_base_type; +#endif + typedef typename stepper_base_type::algebra_type algebra_type; + typedef typename stepper_base_type::value_type value_type; + + + symplectic_rkn_sb3a_m4_mclachlan( const algebra_type &algebra = algebra_type() ) + : stepper_base_type( + detail::symplectic_rkn_sb3a_m4_mclachlan::coef_a_type< value_type >() , + detail::symplectic_rkn_sb3a_m4_mclachlan::coef_b_type< value_type >() , + algebra ) + { } +}; + + +/***************** DOXYGEN ***************/ + +/** + * \class symplectic_rkn_sb3a_m4_mclachlan + * \brief Implementation of the symmetric B3A Runge-Kutta Nystroem method of fifth order. + * + * The method is of fourth order and has five stages. It is described HERE. This method can be used + * with multiprecision types since the coefficients are defined analytically. + * + * ToDo: add reference to paper. + * + * \tparam Order The order of the stepper. + * \tparam Coor The type representing the coordinates q. + * \tparam Momentum The type representing the coordinates p. + * \tparam Value The basic value type. Should be something like float, double or a high-precision type. + * \tparam CoorDeriv The type representing the time derivative of the coordinate dq/dt. + * \tparam MomemtnumDeriv The type representing the time derivative of the momentum dp/dt. + * \tparam Time The type representing the time t. + * \tparam Algebra The algebra. + * \tparam Operations The operations. + * \tparam Resizer The resizer policy. + */ + + /** + * \fn symplectic_rkn_sb3a_m4_mclachlan::symplectic_rkn_sb3a_m4_mclachlan( const algebra_type &algebra ) + * \brief Constructs the symplectic_rkn_sb3a_m4_mclachlan. 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. + */ + +} // namespace odeint +} // namespace numeric +} // namespace boost + + +#endif // BOOST_NUMERIC_ODEINT_STEPPER_SYMPLECTIC_RKN_SB3A_M4_MCLACHLAN_HPP_DEFINED |