is defined by
, where
.
The points x=0 and
are both fixed points
of the map. Unlike the linear map,
calculating the Lyapunov exponent is not trivial
since the derivative
is not constant for the map. We can, however, do a few
computational experiments to better understand this map.
The following links call up the Maple Form Interface. All
the examples considered involve the case b=4, so
. Please read the
explanations in this document before calling up
the Maple Form Interface so that you can be clear
on what each section of code is actually doing.
(Of course, if you are familiar with Maple,
you can decipher the code easily.)
which
is a fixed point of this map. What happens to the
orbit of y0 when y0 is close to
?
Try changing x0 and y0 to see how orbits of
other neighbouring points behave. (If you increase N,
bear in mind that the output may not be easy to read.)
and
N=50. Increase N to make a reasonable guess
as to what the Lyapunov exponent
is.
Change x0 to 0, 0.75 and other values in [0,1]
to see how the approximation
varies.
, Maple returns the number
of iterations required for the separation between
orb(x0) and orb(
) to be multiplied
by 10. Initially, the values
and
are used; try changing them. Is
there any pattern emerging?