Eric Altshuler ela at COLA.IGES.ORG
Mon Feb 16 13:19:47 EST 2009

I think the file 'fake.dat' referred to below must exist, but it can be empty (size 0 bytes).

----- Original Message -----
From: "Arlindo da Silva" <arlindo.dasilva at GMAIL.COM>
Sent: Sunday, February 15, 2009 1:35:59 PM GMT -05:00 US/Canada Eastern
Subject: Re: Resolution

On Sun, Feb 15, 2009 at 12:29 PM, Steven < sweiss at > wrote:


I'm using a 0.5x0.5 resolution for GFS data. Ideally within a grid box,
there could be a few towns and cities that I would like produce data for
e.g. tmp2m at a fixed lat/lon. Is there anyway to get the resolution finer -
say to 0.25x0.25 in order to get more values?

A simple, brute force way is use an interpolation function such as linterp() or re() to defined your variable on a higher resoution grid, then work from that defined variable. For this to work you have to create a fake.ctl that defines this high resolution grid, e.g.,

dset fake.dat
options template
xdef ...
ydef ...
zdef ..
tdef ...
vars 1
var 0 0 dymmy

(the data file fake.dat does not have to exist.) Then,

ga-> open model
ga-> open fake
ga-> set dfile 2 (now you are in the fine resolution dimension environment)
ga> define ts_fine = re(ts.1,0.25)

then use ts_fine in your plots. Another possibility is to use PDEF to have this interpolation done on the fly, behind the scenes.


Arlindo da Silva
dasilva at

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