timestepping::RungeKutta4 Class Reference

Timestep strategy for the explicit 4th order RungeKutta algorithm to solve first order problems in time. More...

#include <rungekutta4.hh>

Inheritance diagram for timestepping::RungeKutta4:

Collaboration diagram for timestepping::RungeKutta4:

List of all members.

Public Member Functions
	RungeKutta4 (concepts::SolverFabric< Real > &fabric, concepts::Operator< Real > &D1, concepts::Operator< Real > &D0, timestepping::TimeVector &trhs, const concepts::Vector< Real > &Y0, Real dt)
	Constructor.
virtual	~RungeKutta4 ()
Protected Member Functions
virtual std::ostream &	info (std::ostream &os) const
	Returns information in an output stream.
virtual void	next ()
	The overloaded member function next() has to calculate the new right hand side and to release the solution vector.
Protected Attributes
Real	dt_
	Time step size.
concepts::Operator< Real > *	liCo_
	Operator of the linear equation system which is solved by the friend class TimeStepping.
concepts::Vector< Real >	rhs_
	The right hand side vector of the linear equation system which is solved by the friend class TimeStepping.
concepts::Vector< Real >	sol_
	The solution vector of the linear equation system which is solved by the friend class TimeStepping.
std::auto_ptr < concepts::Operator< Real > >	solver_
	Solver for the linear system.
Real	t_
	Time of the actual solution.
Private Attributes
concepts::Operator< Real > &	D0_
concepts::Operator< Real > &	D1_
	Space operator.
timestepping::TimeVector &	trhs_
	External driver function.
concepts::Vector< Real >	Yn1_
	Store the latest timestep.
Friends
class	TimeStepping

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Detailed Description

Timestep strategy for the explicit 4th order RungeKutta algorithm to solve first order problems in time.

Please notice that this algorithm is not absolutely stable and may not converge if the stability condition is not fullfilled.

See also:

H. R. Schwarz Numerische Mathematik, Teubner, 1997

Author:

Manuel Walser, 2002

Definition at line 34 of file rungekutta4.hh.

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Constructor & Destructor Documentation

timestepping::RungeKutta4::RungeKutta4	(	concepts::SolverFabric< Real > &	fabric,
		concepts::Operator< Real > &	D1,
		concepts::Operator< Real > &	D0,
		timestepping::TimeVector &	trhs,
		const concepts::Vector< Real > &	Y0,
		Real	dt
	)

Constructor.

Parameters:

fabric	Solver fabric for solving the occuring systems
D1	Space opeartor D1
D0	Space opeartor D0
trhs	Timedependent external driver f(x,t)
Y0	Initial condition y(x,0)
dt	Time step size
alpha	Parameter of the Runge Kutta 4 scheme

virtual timestepping::RungeKutta4::~RungeKutta4

(

)

[virtual]

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Member Function Documentation

virtual std::ostream& timestepping::RungeKutta4::info

(

std::ostream &

os

)

const [protected, virtual]

Returns information in an output stream.

Reimplemented from concepts::OutputOperator.

virtual void timestepping::RungeKutta4::next

(

)

[protected, virtual]

The overloaded member function next() has to calculate the new right hand side and to release the solution vector.

Then the Timestepping solver can set the new solution.

Implements timestepping::TimeStepStrategy.

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Friends And Related Function Documentation

friend class TimeStepping [friend, inherited]

Definition at line 48 of file strategy.hh.

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Member Data Documentation

concepts::Operator<Real> & timestepping::RungeKutta4::D0_ [private]

Definition at line 57 of file rungekutta4.hh.

concepts::Operator<Real>& timestepping::RungeKutta4::D1_ [private]

Space operator.

Definition at line 57 of file rungekutta4.hh.

Real timestepping::TimeStepStrategy::dt_ [protected, inherited]

Time step size.

Definition at line 73 of file strategy.hh.

concepts::Operator<Real>* timestepping::TimeStepStrategy::liCo_ [protected, inherited]

Operator of the linear equation system which is solved by the friend class TimeStepping.

It can be stored as a linear combination of two operators. The exact form depends on the specific scheme.

See also:

TimeStepping

Definition at line 61 of file strategy.hh.

concepts::Vector<Real> timestepping::TimeStepStrategy::rhs_ [protected, inherited]

The right hand side vector of the linear equation system which is solved by the friend class TimeStepping.

See also:

TimeStepping

Definition at line 71 of file strategy.hh.

concepts::Vector<Real> timestepping::TimeStepStrategy::sol_ [protected, inherited]

The solution vector of the linear equation system which is solved by the friend class TimeStepping.

See also:

TimeStepping

Definition at line 66 of file strategy.hh.

std::auto_ptr<concepts::Operator<Real> > timestepping::TimeStepStrategy::solver_ [protected, inherited]

Solver for the linear system.

Definition at line 55 of file strategy.hh.

Real timestepping::TimeStepStrategy::t_ [protected, inherited]

Time of the actual solution.

Definition at line 75 of file strategy.hh.

timestepping::TimeVector& timestepping::RungeKutta4::trhs_ [private]

External driver function.

Definition at line 59 of file rungekutta4.hh.

concepts::Vector<Real> timestepping::RungeKutta4::Yn1_ [private]

Store the latest timestep.

Definition at line 61 of file rungekutta4.hh.

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

• timestepping/rungekutta4.hh