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boost::numeric::odeint::runge_kutta_cash_karp54_classic — The RungeKutta CashKarp method implemented without the generic RungeKutta algorithm.
// In header: <boost/numeric/odeint/stepper/runge_kutta_cash_karp54_classic.hpp> template<typename State, typename Value = double, typename Deriv = State, typename Time = Value, typename Algebra = typename algebra_dispatcher< State >::algebra_type, typename Operations = typename operations_dispatcher< State >::operations_type, typename Resizer = initially_resizer> class runge_kutta_cash_karp54_classic : public explicit_error_stepper_base { public: // types typedef explicit_error_stepper_base< runge_kutta_cash_karp54_classic< ... >,... > stepper_base_type; typedef stepper_base_type::state_type state_type; typedef stepper_base_type::value_type value_type; typedef stepper_base_type::deriv_type deriv_type; typedef stepper_base_type::time_type time_type; typedef stepper_base_type::algebra_type algebra_type; typedef stepper_base_type::operations_type operations_type; typedef stepper_base_type::resizer_type resizer_type; // construct/copy/destruct runge_kutta_cash_karp54_classic(const algebra_type & = algebra_type()); // public member functions template<typename System, typename StateIn, typename DerivIn, typename StateOut, typename Err> void do_step_impl(System, const StateIn &, const DerivIn &, time_type, StateOut &, time_type, Err &); template<typename System, typename StateIn, typename DerivIn, typename StateOut> void do_step_impl(System, const StateIn &, const DerivIn &, time_type, StateOut &, time_type); template<typename StateIn> void adjust_size(const StateIn &); // private member functions template<typename StateIn> bool resize_impl(const StateIn &); };
The RungeKutta CashKarp method is one of the standard methods for solving ordinary differential equations, see en.wikipedia.org/wiki/CashKarp_method. The method is explicit and fulfills the Error Stepper concept. Step size control is provided but continuous output is not available for this method.
This class derives from explicit_error_stepper_base and inherits its interface via CRTP (current recurring template pattern). This class implements the method directly, hence the generic RungeKutta algorithm is not used.
typename State
The state type.
typename Value = double
The value type.
typename Deriv = State
The type representing the time derivative of the state.
typename Time = Value
The time representing the independent variable  the time.
typename Algebra = typename algebra_dispatcher< State >::algebra_type
The algebra type.
typename Operations = typename operations_dispatcher< State >::operations_type
The operations type.
typename Resizer = initially_resizer
The resizer policy type.
runge_kutta_cash_karp54_classic
public
construct/copy/destructrunge_kutta_cash_karp54_classic(const algebra_type & algebra = algebra_type());Constructs the
runge_kutta_cash_karp54_classic
class. This constructor can be used as a default constructor if the algebra has a default constructor.
Parameters: 

runge_kutta_cash_karp54_classic
public member functionstemplate<typename System, typename StateIn, typename DerivIn, typename StateOut, typename Err> void do_step_impl(System system, const StateIn & in, const DerivIn & dxdt, time_type t, StateOut & out, time_type dt, Err & xerr);This method performs one step. The derivative
dxdt
of in
at the time t
is passed to the method. The result is updated outofplace, hence the input is in in
and the output in out
. Futhermore, an estimation of the error is stored in xerr
. Access to this step functionality is provided by explicit_error_stepper_base and do_step_impl
should not be called directly.
Parameters: 

template<typename System, typename StateIn, typename DerivIn, typename StateOut> void do_step_impl(System system, const StateIn & in, const DerivIn & dxdt, time_type t, StateOut & out, time_type dt);This method performs one step. The derivative
dxdt
of in
at the time t
is passed to the method. The result is updated outofplace, hence the input is in in
and the output in out
. Access to this step functionality is provided by explicit_error_stepper_base and do_step_impl
should not be called directly.
Parameters: 

template<typename StateIn> void adjust_size(const StateIn & x);Adjust the size of all temporaries in the stepper manually.
Parameters: 
