#include <RungeKutta.hpp>

Classes
struct	ButcherTableau

Public Member Functions
uint64_t	number_of_substeps () const override
	Number of substeps in this TimeStepper. More...

uint64_t	number_of_substeps_for_error () const override
	Number of substeps in this TimeStepper when providing an error measure for adaptive time-stepping. More...

size_t	number_of_past_steps () const override
	Number of past time steps needed for multi-step method. More...

bool	monotonic () const override
	Whether computational and temporal orderings of operations match. More...

TimeStepId	next_time_id (const TimeStepId &current_id, const TimeDelta &time_step) const override
	The TimeStepId after the current substep. More...

TimeStepId	next_time_id_for_error (const TimeStepId &current_id, const TimeDelta &time_step) const override
	The TimeStepId after the current substep when providing an error measure for adaptive time-stepping. More...

virtual const ButcherTableau &	butcher_tableau () const =0

Public Member Functions inherited from TimeStepper
	WRAPPED_PUPable_abstract (TimeStepper)

template<typename Vars >
void	update_u (const gsl::not_null< Vars * > u, const gsl::not_null< TimeSteppers::History< Vars > * > history, const TimeDelta &time_step) const
	Set `u` to the value at the end of the current substep. More...

template<typename Vars , typename ErrVars >
bool	update_u (const gsl::not_null< Vars * > u, const gsl::not_null< ErrVars * > u_error, const gsl::not_null< TimeSteppers::History< Vars > * > history, const TimeDelta &time_step) const
	Set `u` to the value at the end of the current substep; report the error measure when available. More...

template<typename Vars >
bool	dense_update_u (const gsl::not_null< Vars * > u, const TimeSteppers::History< Vars > &history, const double time) const
	Compute the solution value at a time between steps. To evaluate at a time within a given step, call this method at the start of the step containing the time. The function returns true on success, otherwise the call should be retried after the next substep. More...

virtual size_t	order () const =0
	The convergence order of the stepper. More...

virtual size_t	error_estimate_order () const =0
	The convergence order of the stepper error measure. More...

virtual uint64_t	number_of_substeps () const =0
	Number of substeps in this TimeStepper. More...

virtual uint64_t	number_of_substeps_for_error () const =0
	Number of substeps in this TimeStepper when providing an error measure for adaptive time-stepping. More...

virtual size_t	number_of_past_steps () const =0
	Number of past time steps needed for multi-step method. More...

virtual double	stable_step () const =0
	Rough estimate of the maximum step size this method can take stably as a multiple of the step for Euler's method. More...

virtual bool	monotonic () const =0
	Whether computational and temporal orderings of operations match. More...

virtual TimeStepId	next_time_id (const TimeStepId &current_id, const TimeDelta &time_step) const =0
	The TimeStepId after the current substep. More...

virtual TimeStepId	next_time_id_for_error (const TimeStepId &current_id, const TimeDelta &time_step) const =0
	The TimeStepId after the current substep when providing an error measure for adaptive time-stepping. More...

template<typename Vars >
bool	can_change_step_size (const TimeStepId &time_id, const TimeSteppers::History< Vars > &history) const
	Whether a change in the step size is allowed before taking a step. More...

Additional Inherited Members
Public Types inherited from TimeStepper
using	provided_time_stepper_interfaces = tmpl::list< TimeStepper >

Static Public Attributes inherited from TimeStepper
static constexpr bool	local_time_stepping = false

static constexpr bool	imex = false

Detailed Description

Intermediate base class implementing a generic Runge-Kutta scheme.

Implements most of the virtual methods of TimeStepper for a generic Runge-Kutta method. From the TimeStepper interface, derived classes need only implement order, error_estimate_order, and stable_step, and should not include the TIME_STEPPER_* macros. All other methods are implemented in terms of a Butcher tableau returned by the butcher_tableau function.

Member Function Documentation

◆ monotonic()

bool TimeSteppers::RungeKutta::monotonic ( ) const

overridevirtual

Whether computational and temporal orderings of operations match.

If this method returns true, then, for two time-stepper operations occurring at different simulation times, the temporally earlier operation will be performed first. These operations include RHS evaluation, dense output, and neighbor communication. In particular, dense output never requires performing a RHS evaluation later than the output time, so control systems measurements cannot cause deadlocks.

Warning: This guarantee only holds if the time steps themselves are monotonic, which can be violated during initialization.

Implements TimeStepper.

◆ next_time_id()

TimeStepId TimeSteppers::RungeKutta::next_time_id	(	const TimeStepId &	current_id,
		const TimeDelta &	time_step
	)		const

overridevirtual

The TimeStepId after the current substep.

Implements TimeStepper.

◆ next_time_id_for_error()

TimeStepId TimeSteppers::RungeKutta::next_time_id_for_error	(	const TimeStepId &	current_id,
		const TimeDelta &	time_step
	)		const

overridevirtual

The TimeStepId after the current substep when providing an error measure for adaptive time-stepping.

Certain substep methods (e.g. embedded RK4(3)) require additional steps when providing an error measure of the integration.

Implements TimeStepper.

◆ number_of_past_steps()

size_t TimeSteppers::RungeKutta::number_of_past_steps ( ) const

overridevirtual

Number of past time steps needed for multi-step method.

Implements TimeStepper.

◆ number_of_substeps()

uint64_t TimeSteppers::RungeKutta::number_of_substeps ( ) const

overridevirtual

Number of substeps in this TimeStepper.

Implements TimeStepper.

◆ number_of_substeps_for_error()

uint64_t TimeSteppers::RungeKutta::number_of_substeps_for_error ( ) const

overridevirtual

Number of substeps in this TimeStepper when providing an error measure for adaptive time-stepping.

Details

Certain substep methods (e.g. embedded RK4(3)) require additional steps when providing an error measure of the integration.

Implements TimeStepper.

The documentation for this class was generated from the following file:

src/Time/TimeSteppers/RungeKutta.hpp

Classes

Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ monotonic()

◆ next_time_id()

◆ next_time_id_for_error()

◆ number_of_past_steps()

◆ number_of_substeps()

◆ number_of_substeps_for_error()

Details