Hi monica,
you can try this:
Open name file.ctl or sdfopen name file.nc ( for file 1)
Open name file.ctl or sdfopen name file.nc ( for file 2)
set grads off
set grid off
set lat ' val1' "val2 "
set lon ''val1 ''val2"
-
-
set dfile 1
define a1=ave(ave(aext8.1,z=1,z=18)*18,t=1,t=4)
set dfile 2
define a2=a2=ave(ave(aext8,z=1,z=18)*18,t=1,t=4)
display (or ) d a2-a1
-
-
-
run now, i think it will ok
For futher information you can give more details
Sincerly
Abdoulaye

De : S. Faisal Saeed <faisal.met@gmail.com>
À : Monica Santese <monica.santese@le.infn.it>; regcnet <regcnet@lists.ictp.it>
Envoyé le : Lun 5 juillet 2010, 12h 56min 07s
Objet : Re: [RegCNET] Grid problem!

Hi Monica,

If both the runs have the same resolution then i think you just have to "set lat lat1 lat2" and "set lon lon1 lon2" in Grads, before defining "a1" and also "a2".

Faisal

Dear users,

I have two different files CHE that come from two different runs with different numbers of pixels:

One for iy=200 and jx = 200    and one for iy=185 and jx = 200.

Now, if I want to plot the aerosol optical depth map of the differences between the AOD from the first run and AOD from the second one using :

a1=ave(ave(aext8,z=1,z=18)*18,t=1,t=4) and

a2=ave(ave(aext8,z=1,z=18)*18,t=1,t=4)

dif=a1-a2

I have the error message:

Operation error: Incompatable grids
Dimension ranges aren't equivalent
Dimension = 0
1st grid range = -15 756   2nd = 1 771
Error ocurred at column 6
DEFINE error: Invalid expression.

Is there a way to plot the AOD differences for a lat-lon area that are common to the two files CHE?

Thank you fory your help!!

PhD.Monica Santese
CMCC - Physics Department - University of Salento
via Arnesano - 73100 Lecce, Italy

e-mail: monica.santese@le.infn.it
phone: +39-0832-297502 (office)
             +39-0832-297481 (laboratory)
fax:       +39 -0832-297505
******************************

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