.BG
.FN logo
.TL
Draw the S Logo
.CS
logo(x, y, size=2.5)
.AG x,y
optional coordinates for the center of the logo.  By
default, plotted in lower right of figure.
.AG size
optional size of logo relative to the height of a character.
.GR
.EX
logo() 
.KW aplot
.WR
