New Client Reply - [netCDFDecoders !UKB-233671]: problem decoding grib2 2.5 grad (fwd)

• To: bit-bucket <bit-bucket@xxxxxxxxxxxxxxxx>
• Subject: New Client Reply - [netCDFDecoders !UKB-233671]: problem decoding grib2 2.5 grad (fwd)
• From: Robb Kambic <rkambic@xxxxxxxxxxxxxxxx>
• Date: Wed, 13 Jun 2007 09:17:33 -0600 (MDT)

==============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
rkambic@xxxxxxxxxxxxxxxx                   WWW: http://www.unidata.ucar.edu/
==============================================================================

---------- Forwarded message ----------
Date: Tue, 12 Jun 2007 09:17:33 -0600
From: Olivier-ext RATARD <support@xxxxxxxxxxxxxxxx>
To: rkambic@xxxxxxxxxxxxxxxx
Subject: New Client Reply - [netCDFDecoders !UKB-233671]: problem decoding grib2
      2.5 grad

New Client Reply: problem decoding grib2  2.5 grad

Robb,


I am encoutering this kind of problem on grib2 datafiles with a 2.5
precision on latitude and longitude.

File range
        gfs.t00z.pgrbf192.grib2  to gfs.t00z.pgrbf384.grib2. (noaa ftp
site)

Example of parameter

        Geopotential 1000 hPa.

when using the library on similar file (grib2) with 0.5 precision and 1
precision, everything is working well

I have tried to find any bug in my application without success.

To better describe the problem, here is the process step by step

        After getting all available Grib2Record and  identified the needed
Grib2Record, getting the gdsoffset and pdsOffset

        Calling the method getData( long GdsOffset, long PdsOffset ) of
the  Grib2Record

                In this method, the library is trying to get the
Grib2DataSection with the method  (Grib2DataSection)
                        public Grib2DataSection(boolean getData,
RandomAccessFile raf,
                                Grib2GridDefinitionSection gds,
Grib2DataRepresentationSection drs,
                                Grib2BitMapSection bms )
                                        throws IOException

                the dataTemplateNumber retrieved is 3 for files 2.5. (note
that for files with a 0.5 or 1 precision the dtn value is 1)
                -> so it tries to use the function
complexUnpackingWithSpatial

                        The exception is raised in this method.


Thanks a lot.


Meanwhile,I will continue to test the files


Olivier