1. OVERVIEW:


   XY PLOTTER provides terminal-independent interactive graphics.
Initially, you, the user, should select the terminal type.  Upon
selection of the proper terminal, you will be asked if instructions
are desired.  Next, you are asked for the number of simultaneous
curves you wish to plot.  You may then supply real coordinate pairs
(data) from predefined external files, or enter them via the keyboard.
Finally, a main menu containing several options is displayed.  For
more detailed information on a particular option, consult the
appropriate help file.






The following are the default options of XY PLOTTER:


WINDOW - Defined by the maximum and minimum data points.

PLOT TYPE - Continuous.

LINE TYPE - Solid Line.

INTERPOLATION - Data is not initially interpolated.

TIC MARKS - None.

LABELS - X axis reads 'X-axis'.
         Y axis reads 'Y-axis'.
         Title reads 'XYPLOT Version 2'.


COLOR - (If supported):
        Background color is black.
        Foreground color is white.
        First curve color is magenta.

        (If additional curves are specified):
        Second curve color is yellow.
        Third curve color is white.

SHADING - Unshaded (if supported).

TERMINAL TYPE - MUST always be correctly specified.  NO DEFAULT!!!

DEBUG - Prompts for curve number.

HELP - Menu options.


DATA INPUT - Data MUST be specified via keyboard, or contained in a
             predefined external data file.  The number of data sets
             has a default setting of one, and a maximum of three
             unique sets may be entered (three simultaneous curves).
