Ferret question (max/min on contour)

["Jack J. Katzfey" <jjk@xxxxxxxxxxxx>]

Dear Ferret users,

I have a ferret question which I am sure has been asked before.

Is it possible to plot the maximum and/or minimum values on a 
contour plot?  Ideally, these should be relative max/mins over
the plot, not just the absolute max/min for the whole plot.

Take care,

Jack