NAME

       henon - plot the phase space of the Henon system

SYNOPSIS

       henon -help
         or
       henon  [-width  integer] [-height integer] [-skip integer]
              [-swap] [-points integer] [-delay integer] [-A dou-
              ble]  [-B double] [-ulx double] [-uly double] [-lly
              double] [-box integer] [-bulx double]  [-buly  dou-
              ble]  [-blly  double] [-data] [-inv] [-mag integer]
              [-term string]

DESCRIPTION

       The phase space of the Henon system, which is described by
       the  equation x(t+1) = A - x(t)^2 + B * x(t - 1), is plot-
       ted according to the specified parameters.

OPTIONS

       -width integer
              Width of the plot in pixels.

       -height integer
              Height of the plot in pixels.

       -skip integer
              Number of initial points to skip.

       -swap  Swap the x and y axis?

       -points integer
              Number of points to plot.

       -delay integer
              Time steps to delay for.

       -A double
              Value of the A parameter.

       -B double
              Value of the B parameter.

       -ulx double
              Upper-left corner x-coordinate.

       -uly double
              Upper-left corner y-coordinate.

       -lly double
              Lower-left corner y-coordinate.

       -box integer
              Line width for a box.


       -bulx double
              Box's upper-left x-coordinate.

       -buly double
              Box's upper-left y-coordinate.

       -blly double
              Box's lower-left y-coordinate.

       -data  Don't plot, but print points.

       -inv   Invert all colors?

       -mag integer
              Magnification factor.

       -term string
              How to plot points.

MISCELLANY

       The method for  choosing  the  viewable  region  may  seem
       counter-intuitive  at  first, but it has some nice proper-
       ties.  In particular, selecting the exact (x,  y)  coordi-
       nates  for  the  upper-left  corner and only selecting the
       lower right y coordinate forces both the x and y scales to
       be  identical  since all scales are uniquely determined by
       these values along with the plot width and height.  If you
       then  change the width or height of the plot, the relative
       scales will still match up.  The options for making a  box
       work similarly.

BUGS

       No  sanity  checks  are performed to make sure that any of
       the options make sense.

AUTHOR

       Copyright (c) 1997, Gary William Flake.

       Permission granted for any use according to  the  standard
       GNU ``copyleft'' agreement provided that the author's com-
       ments are neither modified nor removed.   No  warranty  is
       given or implied.