setting region with curvilinear coords

[Andrew Woolf <awo@xxxxxxxxxxxxxxxxxxxx>]

Suppose I have a variable defined on curvilinear coords. I can display
this using the 3-argument version of shade, for instance:

shade my_data,x_grid,y_grid

where x_grid and y_grid give the lon and lat coords.

My question is: can I set the region *based on x_grid and y_grid*,
not i or j?

I want to be able to limit the shaded plot to a rectangular range in lat/lon
space which bears no direct correspondence to the i/j grid coords of my
data.

I could probably do this by regridding, but perhaps there is a more
direct route?

I'm rather new to ferret, so my apologies if this is obvious. I've looked
through documentation and the mail archives, but can't find the
answer.

Cheers,
 - Andrew


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Andrew Woolf  (awo@mail.nerc-essc.ac.uk)
Environmental Systems Science Centre (ESSC)
Reading University
3 Earley Gate
Whiteknights
Reading RG6 6AL
UNITED KINGDOM
Phone: +44 (0)118 931 8741   Fax: +44 (0)118 931 6413
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