# Re: @DDC help

Hi Jimmy,
I see your message never got an answer. I think you can do your
computation; the specifications in square brackets tell Ferret what region
the variable is defined on; leave that definition as is. Then you should be
able to get a subset of the variable on the plot command with qualifiers. Ferret will do only the amount of calculation needed to get the result.

Here is an example (a meaningless definition physically, but using a dataset
with variables in X, Y, and Z for convenience)

yes? use levitus_climatology
yes? let div = temp[i=1:360@ddc,j=1:180,k=1:20] + salt[i=1:360, j=1:180@ddc, k=1:20]

yes? plot/x=0/y=180 div ! a line plot in Z

yes? shade/i=1:75/j=35:65/k=3 div ! A subset in X and Y at one depth

Ansley

jimmyc@iastate.edu wrote:

Ferreters-
I have a model grid of i, j, k of 150, 70, 24.
I computed a new variable using the @DDC qualifier:
div = u[i=1:150@DDC,j=1:70,k=1:24,l=1:12,d=1]+v[i=1:150,j=1:70@DDC,k=1:24,l=1:12,d=1]

This plots just fine when I plot the result over the whole grid. But when I try to plot a portion of the grid, say i=1:75 and j=35:65 I get an error that says something about x axis dimension is not the same size as x dimension (or something to that effect).

When I try to subset the entire calculation it doesn't work either. Does anyone know how to subset the calculation so I can "zoom" into one area without looking at the entire data set?

Thanks for any insight you might have. Hopefully I didnt miss something in the users manual.

--
James Correia Jr.
Ph.D. Candidate in Agricultural Meteorology
President (Dictator) of the ISU Graduate Meteorology Club
Dept. of Agronomy, Iowa State University
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Email: jimmyc@iastate.edu
Phone: 515-294-5587
Web: http://www.mesoscale.iastate.edu/jimmyc/
ISU GMC: http://www.stuorg.iastate.edu/gmc/
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-"Morpheus"

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