ptype ARRAY
ptype NSIDE STYLE                     Define marker symbol

   PTYPE ARRAY causes points to take the shapes specified by ARRAY, which
   is read from data file.


   PTYPE NSIDE STYLE causes points to be drawn as NSIDE-sided polygons
   of style STYLE, where:

   STYLE = 0 : open
	   1 : skeletal (center connected to vertices)
	   2 : starred
           3 : solid

