[ferret_users] variable as a coordinate

[David Wang <climater@xxxxxxxxx>]

Hello Ferreters,

I have both velocity and density variables defined on a cartesian grid. 
Now I'd like to plot velocity against density (instead of depth) on a 
vertical section. I thought about @WEQ, which however only seeks 
velocity at a particular density surface at one time. Any workable ideas?

Thanks very much,
David