mfem::ODESolver Class Reference

Abstract class for solving systems of ODEs: dx/dt = f(x,t) More...

#include <ode.hpp>

Inherited by mfem::ARKODESolver, mfem::BackwardEulerSolver, mfem::CVODESolver, mfem::ExplicitRKSolver, mfem::ForwardEulerSolver, mfem::GeneralizedAlphaSolver, mfem::ImplicitMidpointSolver, mfem::PetscODESolver, mfem::RK2Solver, mfem::RK3SSPSolver, mfem::RK4Solver, mfem::SDIRK23Solver, mfem::SDIRK33Solver, and mfem::SDIRK34Solver.

Collaboration diagram for mfem::ODESolver:

Public Member Functions
	ODESolver ()
virtual void	Init (TimeDependentOperator &f)
	Associate a TimeDependentOperator with the ODE solver. More...
virtual void	Step (Vector &x, double &t, double &dt)=0
	Perform a time step from time t [in] to time t [out] based on the requested step size dt [in]. More...
virtual void	Run (Vector &x, double &t, double &dt, double tf)
	Perform time integration from time t [in] to time tf [in]. More...
virtual	~ODESolver ()

Protected Attributes
TimeDependentOperator *	f
	Pointer to the associated TimeDependentOperator. More...

Detailed Description

Abstract class for solving systems of ODEs: dx/dt = f(x,t)

Definition at line 22 of file ode.hpp.

Constructor & Destructor Documentation

mfem::ODESolver::ODESolver ( )

inline

Definition at line 29 of file ode.hpp.

virtual mfem::ODESolver::~ODESolver ( )

inlinevirtual

Definition at line 96 of file ode.hpp.

Member Function Documentation

virtual void mfem::ODESolver::Init ( TimeDependentOperator &  f )

inlinevirtual

Associate a TimeDependentOperator with the ODE solver.

This method has to be called:

• Before the first call to Step().
• When the dimensions of the associated TimeDependentOperator change.
• When a time stepping sequence has to be restarted.
• To change the associated TimeDependentOperator.

Reimplemented in mfem::PetscODESolver, mfem::GeneralizedAlphaSolver, mfem::ARKODESolver, mfem::SDIRK33Solver, mfem::SDIRK34Solver, mfem::SDIRK23Solver, mfem::ImplicitMidpointSolver, mfem::BackwardEulerSolver, mfem::CVODESolver, mfem::ExplicitRKSolver, mfem::RK4Solver, mfem::RK3SSPSolver, mfem::RK2Solver, and mfem::ForwardEulerSolver.

Definition at line 37 of file ode.hpp.

virtual void mfem::ODESolver::Run ( Vector &  x, double &  t, double &  dt, double  tf  )

inlinevirtual

Perform time integration from time t [in] to time tf [in].

Parameters

[in,out]	x	Approximate solution.
[in,out]	t	Time associated with the approximate solution x.
[in,out]	dt	Time step size.
[in]	tf	Requested final time.

The default implementation makes consecutive calls to Step() until reaching tf. The following rules describe the common behavior of the method:

• The input x [in] is the approximate solution for the input time t [in].
• The input dt [in] is the initial time step size.
• The output dt [out] is the last time step taken by the method which may be smaller or larger than the input dt [in] value, e.g. because of time step control.
• The output value of t [out] is not smaller than tf [in].

Reimplemented in mfem::PetscODESolver.

Definition at line 91 of file ode.hpp.

virtual void mfem::ODESolver::Step ( Vector &  x, double &  t, double &  dt  )

pure virtual

Perform a time step from time t [in] to time t [out] based on the requested step size dt [in].

Parameters

[in,out]	x	Approximate solution.
[in,out]	t	Time associated with the approximate solution x.
[in,out]	dt	Time step size.

The following rules describe the common behavior of the method:

• The input x [in] is the approximate solution for the input time t [in].
• The input dt [in] is the desired time step size, defining the desired target time: t [target] = t [in] + dt [in].
• The output x [out] is the approximate solution for the output time t [out].
• The output dt [out] is the last time step taken by the method which may be smaller or larger than the input dt [in] value, e.g. because of time step control.
• The method may perform more than one time step internally; in this case dt [out] is the last internal time step size.
• The output value of t [out] may be smaller or larger than t [target], however, it is not smaller than t [in] + dt [out], if at least one internal time step was performed.
• The value x [out] may be obtained by interpolation using internally stored data.
• In some cases, the contents of x [in] may not be used, e.g. when x [out] from a previous Step() call was obtained by interpolation.
• In consecutive calls to this method, the output t [out] of one Step() call has to be the same as the input t [in] to the next Step() call.
• If the previous rule has to be broken, e.g. to restart a time stepping sequence, then the ODE solver must be re-initialized by calling Init() between the two Step() calls.

Implemented in mfem::PetscODESolver, mfem::GeneralizedAlphaSolver, mfem::ARKODESolver, mfem::SDIRK33Solver, mfem::SDIRK34Solver, mfem::SDIRK23Solver, mfem::ImplicitMidpointSolver, mfem::BackwardEulerSolver, mfem::CVODESolver, mfem::ExplicitRKSolver, mfem::RK4Solver, mfem::RK3SSPSolver, mfem::RK2Solver, and mfem::ForwardEulerSolver.

Member Data Documentation

TimeDependentOperator* mfem::ODESolver::f

protected

Pointer to the associated TimeDependentOperator.

Definition at line 26 of file ode.hpp.

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

• linalg/ode.hpp