This modules creates a 2-Flist $l=(x_i,h(x_i))$ with $0\leq i<n$,
$x_i = i\cdot s$ and 
$$h(x) = K\cdot x^g.$$
The normalization constant $K$ is equal to 1, unless the \verb+-f+
option is selected, yielding $K=f^{1-g}$ (so that $h(f)=f$).
This module may be used in conjonction with \verb+fcontrast+ to apply
a so-called {\it gamma-correction} on a Fimage.
\index{gamma correction}
