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[GEMPAK #PEV-138471]: Degribbing ECMWF file

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  • Subject: [GEMPAK #PEV-138471]: Degribbing ECMWF file
  • Date: Wed, 11 Jun 2008 01:20:23 -0600
Hi Allan,

re:
> I am trying to run dcgrib2 on an ecmwf model grib file that I get from this
> website http://www.ecmwf.int/products/realtime/d/gts/essential/
> 
> When I use wget or curl to download the file and then run dcgrib2 I get this 
> message:
> found GRIB version 99, maximum expected 2
> 
> However if I right click the file on the webpage and save as, and the run 
> dcgrib2
> on the file it converts fine.

Interesting.  I would not have guessed that a file downloaded using wget would 
be
different than when right clicking on the file and selecting copy.

> I have attached the grib file I used wget to attain and got the above 
> message. I
> thought it was probably a grib table issue, but I have no idea why if I right 
> click
> and save as and manually download the file, the dcgrib2 works fine.

> ANy  ideas?

Not really.

If you really want to get to the bottom of 'how' the two downloads
are different, I suggest grabbing the same file both ways and then using the
binary compare function 'cmp' to see where they are different.  It could be that
the difference is a single byte somewhere in the file (most likely at the 
beginning).
If 'cmp' shows a big difference, I would use 'od' to see what the differences
actually are.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: PEV-138471
Department: Support GEMPAK
Priority: Normal
Status: Closed