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Re: 20040608: Gempak/gdfile....+

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  • Subject: Re: 20040608: Gempak/gdfile....+
  • Date: Thu, 10 Jun 2004 13:59:06 -0400
Hello, Steve:
Solved! We're running v.5.6.j; the priority of upgrading has been low, although I now notice that there are some 
features in newer releases which could be helfpful.
The error we made which prevented the multiple files from being opened was in the gdpfun specification. Or, at least, when we correct the gdpfun line, the files open correctly and we can see what we need to. We'd not used the carat correctly, and seeing it in the example you included tipped us off. I'd not used templating before, in part because I do most of my work with retrospective files, of homogeneous types. Thanks for your help. John - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
Unidata Support wrote:


John,

What version of GEMPAK are you running?

The gdfile line length is 128 characters, so if you
exceed that, you would be out of luck. Then I would suggest making
symbolic links from the full names to filea and fileb like you
outlined.

Another way would be to use the template feature such that you could say
gdfile = ruc2|yymmdd/hhnn+ruc2|yymmdd/hhmm
Any and all should work (comparing against the current version of 5.7.2) I used (excerpted for relevant parameters here): 

GDFILE   = ruc2|040609/1800+ruc2|040609/1900
GDATTIM  = f000
GLEVEL   = 500
GVCORD   = pres
GDPFUN   = hght^040609/1900f000+2 ! hght^040609/1800f000+1
TYPE     = c
CINT     = 60
LINE     = 6 ! 5
TITLE    = 1/-1 ! 1/-2

The above plots the 500mb hghts using the file+1 and file+2 which you
would need if you wanted to use fields from either in a computation
such as:
GDPFUN = sub(hght^040609/1900f000+2,hght^040609/1800f000+1)

You can also suceed with the following if you are not requesting
fields from both files in one computation:
:
GDFILE   = ruc2|040609/1800 ! ruc2|040609/1900
GDPFUN   = hght ! hght

Steve Chiswell
Unidata User Support