MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number > Class Template Reference

#include <explicit_low_storage_runge_kutta_integrator.hpp>

Inheritance diagram for MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >:

Collaboration diagram for MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >:

Public Types
using	VectorType = dealii::LinearAlgebra::distributed::Vector< number >
using	RhsFunctionType = std::function< void(number, number, VectorType &, const VectorType &, std::function< void(unsigned, unsigned)>)>

Public Member Functions
	LowStorageExplicitRungeKuttaIntegrator (const TimeIntegratorData< number > &time_integrator_data)
unsigned int	required_solution_history_size () const override
void	configure_rhs (const RhsFunctionType &compute_rhs_in)
	Configure the function used to compute the right-hand side of the ODE.
void	reinit (const VectorType &vector_template) override
void	reinit (const SolutionHistory< VectorType > &solution_history) override
void	perform_time_step (const number current_time, const number time_step, SolutionHistory< VectorType > &solution_history, const std::function< void(number, number, VectorType &, const VectorType &)> &stage_pre_processing, const std::function< void(number, number, VectorType &, const VectorType &)> &stage_post_processing) override
Public Member Functions inherited from MeltPoolDG::TimeIntegration::TimeIntegratorBase< number >
	TimeIntegratorBase (const TimeIntegratorData< number > &time_integrator_data_in)
virtual	~TimeIntegratorBase ()=default
TimeIntegratorSchemes	get_integrator_type () const
void	set_monitoring_vector (VectorType &monitoring_vector_in)
void	reset_monitoring_vector ()

Private Attributes
std::vector< number >	bi
	Runge-Kutta final update weights.
std::vector< number >	ai
	Runge-Kutta stage weight coefficients.
std::vector< number >	ci
	Runge-Kutta stage time coefficients.
unsigned int	n_stages
	Number of stages of the Runge-Kutta scheme.
dealii::LinearAlgebra::distributed::Vector< number >	rk_register_ri
	Intermediate storage for the Runge-Kutta stage derivatives.
dealii::LinearAlgebra::distributed::Vector< number >	rk_register_ki
	Intermediate storage for the Runge-Kutta stage solutions.
RhsFunctionType	compute_rhs

Additional Inherited Members
Protected Attributes inherited from MeltPoolDG::TimeIntegration::TimeIntegratorBase< number >
const TimeIntegratorData< number >	time_integrator_data
VectorType *	monitoring_vector = nullptr

Member Typedef Documentation

RhsFunctionType

template<typename number >

using MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::RhsFunctionType = std::function<void(number, number, VectorType &, const VectorType &, std::function<void(unsigned, unsigned)>)>

VectorType

template<typename number >

using MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::VectorType = dealii::LinearAlgebra::distributed::Vector<number>

Constructor & Destructor Documentation

LowStorageExplicitRungeKuttaIntegrator()

template<typename number >

MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::LowStorageExplicitRungeKuttaIntegrator ( const TimeIntegratorData< number > &  time_integrator_data )

explicit

Constructor. Set the coefficients for the low storage explicit Runge-Kutta scheme.

Parameters

time_integrator_data

Time integrator data struct setting the scheme of the integrator.

Member Function Documentation

configure_rhs()

template<typename number >

void MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::configure_rhs

(

const RhsFunctionType &

compute_rhs_in

)

Configure the function used to compute the right-hand side of the ODE.

Sets the class member compute_rhs to the provided function. For details on the expected function signature and behavior, see the documentation of the corresponding class member.

Parameters

compute_rhs_in

Function to compute the right-hand side of the ODE.

perform_time_step()

template<typename number >

void MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::perform_time_step ( const number  current_time, const number  time_step, SolutionHistory< VectorType > &  solution_history, const std::function< void(number, number, VectorType &, const VectorType &)> &  stage_pre_processing, const std::function< void(number, number, VectorType &, const VectorType &)> &  stage_post_processing  )

overridevirtual

Perform the actual time integration for a single time step using the low storage explicit Runge-Kutta scheme.

Parameters

current_time	Current time.
time_step	Current time step size.
solution_history	Solution history object providing the current and all required previous solutions.
stage_pre_processing	Function which is executed at the beginning of each Runge-Kutta stage. Three variables are passed to the function: the current time, the vector which is later used in the stage computation, and the current stage solution.
stage_post_processing	Function which is executed at the end of each Runge-Kutta stage. Three variables are passed to the function: the current time after perfoming the stage, the vector which is later used in the subsequent computations, and the solution of the Runge-Kutta stage.

Implements MeltPoolDG::TimeIntegration::TimeIntegratorBase< number >.

reinit() [1/2]

template<typename number >

void MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::reinit ( const SolutionHistory< VectorType > &  solution_history )

overridevirtual

Sets up the necessary internal data structures by internally calling reinit(solution_history.get_current_solution()).

Reimplemented from MeltPoolDG::TimeIntegration::TimeIntegratorBase< number >.

reinit() [2/2]

template<typename number >

void MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::reinit ( const VectorType &  vector_template )

overridevirtual

Allocate memory for the required vectors used during the integration. This function needs to be called once before the function perform_time_step() can be called.

Parameters

vector_template

Reference vector used to define the partitioning for all internal vectors.

Implements MeltPoolDG::TimeIntegration::TimeIntegratorBase< number >.

required_solution_history_size()

template<typename number >

unsigned MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::required_solution_history_size ( ) const

overridevirtual

Returns the number of previous solutions, that is solutions at time step n - x, where x >= 0, required by the time integrator.

Implements MeltPoolDG::TimeIntegration::TimeIntegratorBase< number >.

Member Data Documentation

ai

template<typename number >

std::vector<number> MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::ai

private

Runge-Kutta stage weight coefficients.

bi

template<typename number >

std::vector<number> MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::bi

private

Runge-Kutta final update weights.

ci

template<typename number >

std::vector<number> MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::ci

private

Runge-Kutta stage time coefficients.

compute_rhs

template<typename number >

RhsFunctionType MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::compute_rhs

private

Given an ODE system of the form

\[ y' = F(y), \]

this function computes the right-hand side \(F(y)\).

Function Signature:

void f(number time,
       number time_step,
       VectorType &dst,
       const VectorType &src,
       std::function<void(unsigned, unsigned)> post);

Parameters:

• time : Current simulation time at \(t^n\).
• time_step : Current step size \(\Delta t\).
• dst : Destination vector for the RHS result.
• src : Source solution vector \(y^n\).
• post : Post-processing function applied after computing the RHS. Receives a range of global indices [begin, end) to process, ensuring all indices are handled. Designed for efficient integration with deal.II’s matrix-free framework.

n_stages

template<typename number >

unsigned int MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::n_stages

private

Number of stages of the Runge-Kutta scheme.

rk_register_ki

template<typename number >

dealii::LinearAlgebra::distributed::Vector<number> MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::rk_register_ki

private

Intermediate storage for the Runge-Kutta stage solutions.

rk_register_ri

template<typename number >

dealii::LinearAlgebra::distributed::Vector<number> MeltPoolDG::TimeIntegration::LowStorageExplicitRungeKuttaIntegrator< number >::rk_register_ri

private

Intermediate storage for the Runge-Kutta stage derivatives.

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

• include/meltpooldg/time_integration/explicit_low_storage_runge_kutta_integrator.hpp
• source/time_integration/explicit_low_storage_runge_kutta_integrator.cpp