ODE simulator - Instructions

Parameters

a,b,c,d	Parameters of dynamical equations
dt	Time step for plotting evolution
x-ax	Variable plotted on horizontal axis (0=time, 1=X, 2=Y, 3=Z)
y-ax	Variable plotted on vertical axis
X0,Y0,Z0	Initial values for X,Y,Z
tran	Time of evolution to eliminate transient before plotting
dX0,dY0,dZ0	Timeseries: Small change in initial values
Interval	Spectrum: data is accumulated every Interval time steps
Points	Spectrum: number of data points for each transform
Window	Spectrum: type of window used in calculating power spectrum
Variable	Poincare, ReturnMap, MaxMap, Reconstruction: variable used for section or maximum
Section	Poincare, ReturnMap: value of Variable at section
Variable	Reconstruction: variable used for reconstruction
Delay	Reconstruction: delay as multiple of dt
PlotMark	Poincare, ReturnMap, MaxMap: Size of mark plotted (0=dot)

Remarks

If you change a text entry, you must hit Enter or Return on the keyboard, or Reset within the applet for the change to take effect.
The slider changes the speed of the iteration. Setting the speed too high may make the applet unresponsive or crash, depending on the Java implementation. Setting to a lower speed increases the accuracy of the numerical solver, by setting a smaller iteration time step for the solver (not the plotting). However you will usually want to increase the speed from the default value.
Allow sleep: allows the applet to sleep after each iteration to allow the screen updates to catch up. Applet may crash if set to "No", depending on the Java implementation: if not, the program will run faster.
Show Time: switches continuous update of time of iterations. Some Java implementations have an annoying screen flash if set to "Yes".
The Error indicated is the sum of the errors in the quantities plotted over a single iteration time step as estimated from the integrating routine by comparing with results obtained by halving the time step.
Show Ghost: switches whether to show a pre-image of the trajectory
Clicking on the running plot will start a new evolution from that point as initial condition (the third coordinate, not plotted, is unchanged).
In the Poincare section and map plots, regions of interest may be enlarged by selecting the desired region by dragging the mouse on the stopped plot.
Reset or a click outside the stationary plot restarts from the initial condition, and sets the axes range to default values. Clear simply erases the plot but continues the same run.

[Diagnostics] [Equations]

Last modified Thursday, December 9, 1999
Michael Cross