org.opensourcephysics.sip.ch04
Class Pendulum

java.lang.Object
  org.opensourcephysics.sip.ch04.Pendulum

All Implemented Interfaces:

Drawable, ODE

public class Pendulum
extends java.lang.Object
implements Drawable, ODE

Pendulum models the dynamics of a pendulum.

Constructor Summary

Pendulum()

Method Summary

void	draw(DrawingPanel drawingPanel, java.awt.Graphics g) Draws the pendulum.
void	getRate(double[] state, double[] rate) Gets the rate.
double[]	getState() Gets the state.
void	setState(double theta, double thetaDot) Sets the state.
void	setStepSize(double dt) Sets the ODESolver's time step.
void	step() Steps (advances) the time.

Methods inherited from class java.lang.Object

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

Constructor Detail

Pendulum

public Pendulum()

Method Detail

setStepSize

public void setStepSize(double dt)

Sets the ODESolver's time step.

Parameters:

dt - double

step

public void step()

Steps (advances) the time.

Parameters:

dt - the time step.

setState

public void setState(double theta,
                     double thetaDot)

Sets the state.

Parameters:

theta -

dtheta/dt -

getState

public double[] getState()

Gets the state. Required for ODE interface.

Specified by:

getState in interface ODE

Returns:

double[] the state

getRate

public void getRate(double[] state,
                    double[] rate)

Gets the rate. Required for ODE inteface

Specified by:

getRate in interface ODE

Parameters:

state - double[] the state

rate - double[] the computed rate

draw

public void draw(DrawingPanel drawingPanel,
                 java.awt.Graphics g)

Draws the pendulum. Required for Drawable interface.

Specified by:

draw in interface Drawable

Parameters:

drawingPanel -

g -