period doubling applet:<br />

<applet width="321" height="241" archive="period11.jar" code="PeriodDoubling2.class">
[This is an applet]
</applet>
<p>
parameter values are: mu, a, b, k (across the top) and  x, y (below); see "A Per
iod Doubling Route to Chaos in A Sigmoid Perceptron Pair" for details on what th
ey mean.  (x and y are the "current state" of the two neurons; a is w11, ak is w
12; b = w21, bk=w22, mu is the exponent in the sigmoid; the larger it is, the mo
re it approximates a step function).
</p>
<p>
a=-5, b=-25, k=-1, mu=6: good for chaos. (note x=.5, y=.5 is a fixed point here!)
</p>