Manual
Buttons
- Reset: Sets the values of the parameters to those shown
in the boxes and reinitializes the plot (e.g. resets the initial
value to x0).
- Clear: Clears the plot, but does not reset the
parameter values and maintains the current value of x .
- Step: Performs and plots one step in the iteration.
- Start: Starts repeated iteration and plotting with a
time between plotting set by the delay parameter (in ms).
Clear can be used while the iterations are proceeding if
the display becomes scrambled.
- Stop: Stops the iteration and allows the parameters to
be updated.
Text Boxes
Note that the parameter values are not updated until either
Enter is hit on the keyboard or the Reset button is
pushed.
- nf: The function f (2 nf) is iterated
and plotted.
- nsc: Rescaling parameter. The central portion of
x and f (i.e. near x=0.5 are expanded by the
factor (-2.502907875)nsc. The actual range of
x and f plotted are indicated as the "full scale" on
the plot.
- x0: Initial value of x expressed as a fraction
of the range of the plot (i.e. involves the rescaling set by
nsc and scale).
- scale: Further modifies the range of x and
f plotted by multiplying by the factor scale - again
indicated in the "full scale" shown on the plot. Useful for "fine
tuning" the plot.
- trans: Sets the number of iterations done before values
are plotted. Useful to eliminate transient behavior if desired.
- a: Sets the value of a in the maps. Value can be
typed in or set by the drop down box values below.
Drop-down boxes
It turns out to be useful to look at a sequence of values of
a, a0 , a1 .... given by
am = ac - C
-m
where ac depends on the map function , but
= 4.6692016091... for all maps. The value of m can be
used to step through values of a yielding 2m
orbits (the symbol I in the list box for m corresponds to
infinity i.e. a=ac). The value of C can be
chosen to give particular "types" of orbit.
The list boxes respectively:
- set the map to be iterated and ac
- set whether a > ac (+) or
a < ac (-)
- set the value of C giving values of a
corresponding to
- Superstable: one point on orbit at maximum of
f.
- Instability: cycle just unstable.
- Bandmerging: chaotic bands merge in chaotic region
for a > ac.
- set the value of m
Values can also be typed directly into the text boxes (remember to
Enter or Reset).
Scroll bar
- Speed: sets speed of iteration and animation, roughly
in iterations per second.
Mouse Click
- Clicking the mouse within the plot area starts a new
iteration with an initial value given by the horizontal position.
(The vertical position has no effect.)
[Return to Home Page]
Last modified 18 August, 2009
Michael Cross