Description
Draws a hexagon on the current graphic device
Usage
hexagon(x,y,unitcell=1,col=NA,border="black")
Arguments
 
- x,y
- x and y position of the bottom left corner of the square that
  would pack into the same space as the hexagon. 
 
- unitcell
- The dimension of the side of the abovementioned square. 
 
- col
- The color to fill the hexagon - default is no fill. 
 
- border
- The color of the perimeter of the hexagon.