void legpos (entries, xleg, yleg, border) LEGEND.C Level 1
int entries The number of legend entries.
float xleg, yleg The x and y position of the upper left hand corner of the legend in inches (or cm) on the full-page output.
int border = 0 No border will be drawn around the legend.
= 1 A border will be drawn around the legend.
legpos() sets the position of the legend. This routine also saves the current color and causes the text portion of 
the legend to be in this color. If you wish to have your legend text in a different color, you need to call color() before the call to legpos(). legpos() must be called before legend(), and the number of calls to legend() must equal entries. The legend box will not exclude plotted objects until there have been entries number of calls to legend().