Package org.opensourcephysics.numerics

Class Euler

java.lang.Object

org.opensourcephysics.numerics.AbstractODESolver

org.opensourcephysics.numerics.Euler

All Implemented Interfaces:

ODESolver

public class Euler
extends AbstractODESolver

Euler implements an Euler method ODE solver. The Euler method is unstable for many systems. It is included as an example of how to use the ODE and ODESolver interface.

Field Summary

Fields

Modifier and Type	Field	Description
protected double[]	rate

Fields inherited from class org.opensourcephysics.numerics.AbstractODESolver

numEqn, ode, stepSize

Constructor Summary

Constructors

Constructor	Description
Euler(ODE ode)	Constructs the Euler ODESolver for a system of ordinary differential equations.

Method Summary

Modifier and Type	Method	Description
void	initialize(double stepSize)	Initializes the ODE solver and allocates the rate array.
double	step()	Steps (advances) the differential equations by the stepSize.

Methods inherited from class org.opensourcephysics.numerics.AbstractODESolver

getStepSize, setStepSize

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

rate

protected double[] rate

Constructor Detail

Euler

public Euler(ODE ode)

Constructs the Euler ODESolver for a system of ordinary differential equations.

Parameters:

ode - the system of differential equations.

Method Detail

initialize

public void initialize(double stepSize)

Initializes the ODE solver and allocates the rate array. The number of differential equations is determined by invoking getState().length on the superclass.

Specified by:

initialize in interface ODESolver

Overrides:

initialize in class AbstractODESolver

Parameters:

stepSize -

step

public double step()

Steps (advances) the differential equations by the stepSize. The ODESolver invokes the ODE's getState method to obtain the initial state of the system. The ODESolver then advances the solution and copies the new state into the state array at the end of the solution step.

Specified by:

step in interface ODESolver

Specified by:

step in class AbstractODESolver

Returns:

the step size