ceph/src/boost/libs/numeric/odeint/include/boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp

   1 /*
   2  [auto_generated]
   3  boost/numeric/odeint/stepper/explicit_error_generic_rk.hpp
   4
   5  [begin_description]
   6  Implementation of the generic Runge Kutta error stepper. Base class for many RK error steppers.
   7  [end_description]
   8
   9  Copyright 2011-2013 Mario Mulansky
  10  Copyright 2011-2013 Karsten Ahnert
  11  Copyright 2012 Christoph Koke
  12
  13  Distributed under the Boost Software License, Version 1.0.
  14  (See accompanying file LICENSE_1_0.txt or
  15  copy at http://www.boost.org/LICENSE_1_0.txt)
  16  */
  17
  18
  19 #ifndef BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_ERROR_GENERIC_RK_HPP_INCLUDED
  20 #define BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_ERROR_GENERIC_RK_HPP_INCLUDED
  21
  22 #include <boost/numeric/odeint/stepper/base/explicit_error_stepper_base.hpp>
  23
  24 #include <boost/numeric/odeint/algebra/default_operations.hpp>
  25 #include <boost/numeric/odeint/algebra/range_algebra.hpp>
  26 #include <boost/numeric/odeint/algebra/algebra_dispatcher.hpp>
  27 #include <boost/numeric/odeint/algebra/operations_dispatcher.hpp>
  28 #include <boost/numeric/odeint/stepper/detail/generic_rk_algorithm.hpp>
  29 #include <boost/numeric/odeint/stepper/detail/generic_rk_call_algebra.hpp>
  30 #include <boost/numeric/odeint/stepper/detail/generic_rk_operations.hpp>
  31
  32 #include <boost/numeric/odeint/util/state_wrapper.hpp>
  33 #include <boost/numeric/odeint/util/is_resizeable.hpp>
  34 #include <boost/numeric/odeint/util/resizer.hpp>
  35
  36
  37
  38 namespace boost {
  39 namespace numeric {
  40 namespace odeint {
  41
  42
  43 template<
  44 size_t StageCount,
  45 size_t Order,
  46 size_t StepperOrder ,
  47 size_t ErrorOrder ,
  48 class State ,
  49 class Value = double ,
  50 class Deriv = State ,
  51 class Time = Value ,
  52 class Algebra = typename algebra_dispatcher< State >::algebra_type ,
  53 class Operations = typename operations_dispatcher< State >::operations_type ,
  54 class Resizer = initially_resizer
  55 >
  56 #ifndef DOXYGEN_SKIP
  57 class explicit_error_generic_rk
  58 : public explicit_error_stepper_base<
  59   explicit_error_generic_rk< StageCount , Order , StepperOrder , ErrorOrder , State ,
  60   Value , Deriv , Time , Algebra , Operations , Resizer > ,
  61   Order , StepperOrder , ErrorOrder , State , Value , Deriv , Time , Algebra ,
  62   Operations , Resizer >
  63 #else
  64 class explicit_error_generic_rk : public explicit_error_stepper_base
  65 #endif
  66 {
  67
  68 public:
  69 #ifndef DOXYGEN_SKIP
  70     typedef explicit_error_stepper_base<
  71             explicit_error_generic_rk< StageCount , Order , StepperOrder , ErrorOrder , State ,
  72             Value , Deriv , Time , Algebra , Operations , Resizer > ,
  73             Order , StepperOrder , ErrorOrder , State , Value , Deriv , Time , Algebra ,
  74             Operations , Resizer > stepper_base_type;
  75 #else
  76     typedef explicit_stepper_base< ... > stepper_base_type;
  77 #endif
  78     typedef typename stepper_base_type::state_type state_type;
  79     typedef typename stepper_base_type::wrapped_state_type wrapped_state_type;
  80     typedef typename stepper_base_type::value_type value_type;
  81     typedef typename stepper_base_type::deriv_type deriv_type;
  82     typedef typename stepper_base_type::wrapped_deriv_type wrapped_deriv_type;
  83     typedef typename stepper_base_type::time_type time_type;
  84     typedef typename stepper_base_type::algebra_type algebra_type;
  85     typedef typename stepper_base_type::operations_type operations_type;
  86     typedef typename stepper_base_type::resizer_type resizer_type;
  87 #ifndef DOXYGEN_SKIP
  88     typedef explicit_error_generic_rk< StageCount , Order , StepperOrder , ErrorOrder , State ,
  89             Value , Deriv , Time , Algebra , Operations , Resizer > stepper_type;
  90 #endif
  91     typedef detail::generic_rk_algorithm< StageCount , Value , Algebra , Operations > rk_algorithm_type;
  92
  93     typedef typename rk_algorithm_type::coef_a_type coef_a_type;
  94     typedef typename rk_algorithm_type::coef_b_type coef_b_type;
  95     typedef typename rk_algorithm_type::coef_c_type coef_c_type;
  96
  97     static const size_t stage_count = StageCount;
  98
  99 private:
 100
 101
 102 public:
 103
 104     // we use an explicit_generic_rk to do the normal rk step
 105     // and add a separate calculation of the error estimate afterwards
 106     explicit_error_generic_rk( const coef_a_type &a ,
 107             const coef_b_type &b ,
 108             const coef_b_type &b2 ,
 109             const coef_c_type &c ,
 110             const algebra_type &algebra = algebra_type() )
 111     : stepper_base_type( algebra ) , m_rk_algorithm( a , b , c ) , m_b2( b2 )
 112     { }
 113
 114
 115     template< class System , class StateIn , class DerivIn , class StateOut , class Err >
 116     void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt ,
 117             time_type t , StateOut &out , time_type dt , Err &xerr )
 118     {
 119         // normal step
 120         do_step_impl( system , in , dxdt , t , out , dt );
 121
 122         // additionally, perform the error calculation
 123         detail::template generic_rk_call_algebra< StageCount , algebra_type >()( stepper_base_type::m_algebra ,
 124                 xerr , dxdt , m_F , detail::generic_rk_scale_sum_err< StageCount , operations_type , value_type , time_type >( m_b2 , dt) );
 125     }
 126
 127
 128     template< class System , class StateIn , class DerivIn , class StateOut >
 129     void do_step_impl( System system , const StateIn &in , const DerivIn &dxdt ,
 130             time_type t , StateOut &out , time_type dt )
 131     {
 132         m_resizer.adjust_size( in , detail::bind( &stepper_type::template resize_impl< StateIn > , detail::ref( *this ) , detail::_1 ) );
 133
 134         // actual calculation done in generic_rk.hpp
 135         m_rk_algorithm.do_step( stepper_base_type::m_algebra , system , in , dxdt , t , out , dt , m_x_tmp.m_v , m_F );
 136     }
 137
 138
 139     template< class StateIn >
 140     void adjust_size( const StateIn &x )
 141     {
 142         resize_impl( x );
 143         stepper_base_type::adjust_size( x );
 144     }
 145
 146
 147 private:
 148
 149     template< class StateIn >
 150     bool resize_impl( const StateIn &x )
 151     {
 152         bool resized( false );
 153         resized |= adjust_size_by_resizeability( m_x_tmp , x , typename is_resizeable<state_type>::type() );
 154         for( size_t i = 0 ; i < StageCount-1 ; ++i )
 155         {
 156             resized |= adjust_size_by_resizeability( m_F[i] , x , typename is_resizeable<deriv_type>::type() );
 157         }
 158         return resized;
 159     }
 160
 161
 162     rk_algorithm_type m_rk_algorithm;
 163     coef_b_type m_b2;
 164
 165     resizer_type m_resizer;
 166
 167     wrapped_state_type m_x_tmp;
 168     wrapped_deriv_type m_F[StageCount-1];
 169
 170 };
 171
 172
 173 /********* DOXYGEN *********/
 174
 175 /**
 176  * \class explicit_error_generic_rk
 177  * \brief A generic implementation of explicit Runge-Kutta algorithms with error estimation. This class is as a
 178  * base class for all explicit Runge-Kutta steppers with error estimation.
 179  *
 180  * This class implements the explicit Runge-Kutta algorithms with error estimation in a generic way.
 181  * The Butcher tableau is passed to the stepper which constructs the stepper scheme with the help of a
 182  * template-metaprogramming algorithm. ToDo : Add example!
 183  *
 184  * This class derives explicit_error_stepper_base which provides the stepper interface.
 185  *
 186  * \tparam StageCount The number of stages of the Runge-Kutta algorithm.
 187  * \tparam Order The order of a stepper if the stepper is used without error estimation.
 188  * \tparam StepperOrder The order of a step if the stepper is used with error estimation. Usually Order and StepperOrder have
 189  * the same value.
 190  * \tparam ErrorOrder The order of the error step if the stepper is used with error estimation.
 191  * \tparam State The type representing the state of the ODE.
 192  * \tparam Value The floating point type which is used in the computations.
 193  * \tparam Time The type representing the independent variable - the time - of the ODE.
 194  * \tparam Algebra The algebra type.
 195  * \tparam Operations The operations type.
 196  * \tparam Resizer The resizer policy type.
 197  */
 198
 199
 200     /**
 201      * \fn explicit_error_generic_rk::explicit_error_generic_rk( const coef_a_type &a , const coef_b_type &b , const coef_b_type &b2 , const coef_c_type &c , const algebra_type &algebra )
 202      * \brief Constructs the explicit_error_generik_rk class with the given parameters a, b, b2 and c. See examples section for details on the coefficients.
 203      *
 204      * \param a Triangular matrix of parameters b in the Butcher tableau.
 205      * \param b Last row of the butcher tableau.
 206      * \param b2 Parameters for lower-order evaluation to estimate the error.
 207      * \param c Parameters to calculate the time points in the Butcher tableau.
 208      * \param algebra A copy of algebra is made and stored inside explicit_stepper_base.
 209      */
 210
 211
 212     /**
 213      * \fn explicit_error_generic_rk::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt , time_type t , StateOut &out , time_type dt , Err &xerr )
 214      * \brief This method performs one step. The derivative `dxdt` of `in` at the time `t` is passed to the method.
 215      * The result is updated out-of-place, hence the input is in `in` and the output in `out`. Futhermore, an
 216      * estimation of the error is stored in `xerr`. `do_step_impl` is used by explicit_error_stepper_base.
 217      *
 218      * \param system The system function to solve, hence the r.h.s. of the ODE. It must fulfill the
 219      *               Simple System concept.
 220      * \param in The state of the ODE which should be solved. in is not modified in this method
 221      * \param dxdt The derivative of x at t.
 222      * \param t The value of the time, at which the step should be performed.
 223      * \param out The result of the step is written in out.
 224      * \param dt The step size.
 225      * \param xerr The result of the error estimation is written in xerr.
 226      */
 227
 228     /**
 229      * \fn explicit_error_generic_rk::do_step_impl( System system , const StateIn &in , const DerivIn &dxdt , time_type t , StateOut &out , time_type dt )
 230      * \brief This method performs one step. The derivative `dxdt` of `in` at the time `t` is passed to the method.
 231      * The result is updated out-of-place, hence the input is in `in` and the output in `out`.
 232      * Access to this step functionality is provided by explicit_stepper_base and
 233      * `do_step_impl` should not be called directly.
 234      *
 235      * \param system The system function to solve, hence the r.h.s. of the ODE. It must fulfill the
 236      *               Simple System concept.
 237      * \param in The state of the ODE which should be solved. in is not modified in this method
 238      * \param dxdt The derivative of x at t.
 239      * \param t The value of the time, at which the step should be performed.
 240      * \param out The result of the step is written in out.
 241      * \param dt The step size.
 242      */
 243
 244     /**
 245      * \fn explicit_error_generic_rk::adjust_size( const StateIn &x )
 246      * \brief Adjust the size of all temporaries in the stepper manually.
 247      * \param x A state from which the size of the temporaries to be resized is deduced.
 248      */
 249
 250 }
 251 }
 252 }
 253
 254
 255 #endif // BOOST_NUMERIC_ODEINT_STEPPER_EXPLICIT_ERROR_GENERIC_RK_HPP_INCLUDED