#include <deal.II/base/time_stepping.h>

Inheritance diagram for TimeStepping::EmbeddedExplicitRungeKutta< VectorType >:

Classes
struct	Status

Public Member Functions
	EmbeddedExplicitRungeKutta ()=default

	EmbeddedExplicitRungeKutta (const runge_kutta_method method, const double coarsen_param=1.2, const double refine_param=0.8, const double min_delta=1e-14, const double max_delta=1e100, const double refine_tol=1e-8, const double coarsen_tol=1e-12)

	~EmbeddedExplicitRungeKutta () override

void	free_memory ()

void	initialize (const runge_kutta_method method) override

double	evolve_one_time_step (const std::function< VectorType(const double, const VectorType &)> &f, const std::function< VectorType(const double, const double, const VectorType &)> &id_minus_tau_J_inverse, double t, double delta_t, VectorType &y) override

double	evolve_one_time_step (const std::function< VectorType(const double, const VectorType &)> &f, double t, double delta_t, VectorType &y)

void	set_time_adaptation_parameters (const double coarsen_param, const double refine_param, const double min_delta, const double max_delta, const double refine_tol, const double coarsen_tol)

const Status &	get_status () const override

Public Member Functions inherited from TimeStepping::RungeKutta< VectorType >
virtual	~RungeKutta () override=default

double	evolve_one_time_step (std::vector< std::function< VectorType(const double, const VectorType &)>> &F, std::vector< std::function< VectorType(const double, const double, const VectorType &)>> &J_inverse, double t, double delta_t, VectorType &y) override

Public Member Functions inherited from TimeStepping::TimeStepping< VectorType >
virtual	~TimeStepping ()=default

Private Member Functions
void	compute_stages (const std::function< VectorType(const double, const VectorType &)> &f, const double t, const double delta_t, const VectorType &y, std::vector< VectorType > &f_stages)

Private Attributes
double	coarsen_param

double	refine_param

double	min_delta_t

double	max_delta_t

double	refine_tol

double	coarsen_tol

bool	last_same_as_first

std::vector< double >	b1

std::vector< double >	b2

VectorType *	last_stage

Status	status

Additional Inherited Members
Protected Attributes inherited from TimeStepping::RungeKutta< VectorType >
unsigned int	n_stages

std::vector< double >	b

std::vector< double >	c

std::vector< std::vector< double > >	a

Detailed Description

template<typename VectorType>
class TimeStepping::EmbeddedExplicitRungeKutta< VectorType >

This is class is derived from RungeKutta and implement embedded explicit methods.

Definition at line 479 of file time_stepping.h.

Constructor & Destructor Documentation

template<typename VectorType>

TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::EmbeddedExplicitRungeKutta ( )

default

Default constructor. initialize(runge_kutta_method) and set_time_adaptation_parameters(double, double, double, double, double, double) need to be called before the object can be used.

template<typename VectorType>

TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::EmbeddedExplicitRungeKutta	(	const runge_kutta_method	method,
		const double	coarsen_param = `1.2`,
		const double	refine_param = `0.8`,
		const double	min_delta = `1e-14`,
		const double	max_delta = `1e100`,
		const double	refine_tol = `1e-8`,
		const double	coarsen_tol = `1e-12`
	)

Constructor. This function calls initialize(runge_kutta_method) and initialize the parameters needed for time adaptation.

template<typename VectorType>

TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::~EmbeddedExplicitRungeKutta ( )

inlineoverride

Destructor.

Definition at line 506 of file time_stepping.h.

Member Function Documentation

template<typename VectorType>

void TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::free_memory ( )

If necessary, deallocate memory allocated by the object.

template<typename VectorType>

void TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::initialize ( const runge_kutta_method method )

overridevirtual

Initialize the embedded explicit Runge-Kutta method.

Implements TimeStepping::RungeKutta< VectorType >.

template<typename VectorType>

double TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::evolve_one_time_step	(	const std::function< VectorType(const double, const VectorType &)> &	f,
		const std::function< VectorType(const double, const double, const VectorType &)> &	id_minus_tau_J_inverse,
		double	t,
		double	delta_t,
		VectorType &	y
	)

overridevirtual

This function is used to advance from time t to t+ delta_t. f is the function \( f(t,y) \) that should be integrated, the input parameters are the time t and the vector y and the output is value of f at this point. id_minus_tau_J_inverse is a function that computes \( inv(I-\tau J)\) where \( I \) is the identity matrix, \( \tau \) is given, and \( J \) is the Jacobian \( \frac{\partial J}{\partial y} \). The input parameters are the time, \( \tau \), and a vector. The output is the value of function at this point. evolve_one_time_step returns the time at the end of the time step.

Implements TimeStepping::RungeKutta< VectorType >.

template<typename VectorType>

double TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::evolve_one_time_step	(	const std::function< VectorType(const double, const VectorType &)> &	f,
		double	t,
		double	delta_t,
		VectorType &	y
	)

This function is used to advance from time t to t+ delta_t. This function is similar to the one derived from TimeStepping, but does not required id_minus_tau_J_inverse because it is not used for explicit methods. evolve_one_time_step returns the time at the end of the time step.

template<typename VectorType>

void TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::set_time_adaptation_parameters	(	const double	coarsen_param,
		const double	refine_param,
		const double	min_delta,
		const double	max_delta,
		const double	refine_tol,
		const double	coarsen_tol
	)

Set the parameters necessary for the time adaptation.

template<typename VectorType>

const Status& TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::get_status ( ) const

overridevirtual

Return the status of the current object.

Implements TimeStepping::TimeStepping< VectorType >.

template<typename VectorType>

void TimeStepping::EmbeddedExplicitRungeKutta< VectorType >::compute_stages	(	const std::function< VectorType(const double, const VectorType &)> &	f,
		const double	t,
		const double	delta_t,
		const VectorType &	y,
		std::vector< VectorType > &	f_stages
	)