Syntax: ASPECT A

   Set the aspect ratio (Y/X) to be A; This is used in drawing
characters and points. If A is exactly 0, the current aspect ratio is
printed. It is reset when a new DEVICE command is issued.

   Usually the aspect ratio is calculated by SM to make characters
look right (and to make square points square), but it is sometimes
useful to override this, especially when positioning labels on graphs
that will be plotted on printers of different aspect ratios.