[gradsusr] Problem extracting HIRLAM gribfile

[Jonas Kaufmann]

Hello Wesley,

thank you for your help! I could convert the file to grib2 using ECMWF
grib_set, see the converted file as an attachment. I then used the
latest versions of g2ctl and wgrib2 to create a control file (also
attached). During this process I get the following error):
Argument "0.000000:winds(grid)" isn't numeric in multiplication (*) at
/usr/share/perl/5.10/Math/Trig.pm line 87.

Now when I try to create an index file for the grib2-file, gribmap
complains with this error:
Open Error:  Missing or invalid dimension increment value
  --> The invalid description file record is:
  --> xdef 351 linear 245.437796901893 -0.459621342512909
  The data file was not opened.

Is there a simple (manual?) way to fix this in the control file? Or is
there another option on how to display data from this file?

Thank you for your help!


Best regards,
Jonas Kaufmann

On Fri, Mar 11, 2011 at 20:08, Wesley Ebisuzaki
<Wesley.Ebisuzaki at noaa.gov> wrote:
> Jonas,
>
>   Your grib1 file is packed using "complex packing".  This kind of
> packing is
> not supported by grib2ctl and GrADS.
>
>   I think that you are getting the error message because the grid is
> (582 x 424) or 246768 points.
> However, the number of grid points (could be modified by undefineds and
> runs of identical values)
> is given by octets 19-20 in section 4. Since 246768 much too big to be
> stored in a 2 byte number,
> an error is flagged.  Try converting this file to grib2 using the ECMWF
> software.  Once in grib2,
> g2ctl and GrADS can read it.  I don't think that g2ctl will handle the
> projection right but at least you
> can display it as a x-y grid.
>
>> http://www.nco.ncep.noaa.gov/pmb/docs/on388/section4.html
>
>
>    Wesley Ebisuzaki
>
> Jonas Kaufmann wrote:
>> Hello,
>>
>> I ran into a problem trying to extract a HIRLAM data set on a rotated
>> lat-lon grid. the file is in grib1-format. I could create a valid
>> control file using the code from g2ctl.pl for grib2-files, merging
>> this together with the code in grib2ctl.pl for grib1 files. Although a
>> control file is created, I also get errors like:
>>
>> grib header at record 1: two values of nxny 246768 144639
>>    LEN 162734 DataStart 14 UnusedBits 6 #Bits 9 nxny 246768
>>
>> When I then go ahead and try to plot a map using GrADS, I always get
>> "Entire Grid undefined". I have attached the grib file, the index file
>> and the control file.
>>
>> What am I doing wrong? How can I extract the data from this gribfile?
>>
>> Thank you for your help!
>>
>> Best regards,
>> Jonas Kaufmann
>> ------------------------------------------------------------------------
>>
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