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[netCDFDecoders #TBM-719686]: documentation for GRIBJava?

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  • Subject: [netCDFDecoders #TBM-719686]: documentation for GRIBJava?
  • Date: Tue, 03 Feb 2009 17:13:52 -0700
Michael,

In the home dir of the package there is a file IndexFormat.txt that
explains the GribIndex format.


You need to create a Grib2 index. ie

%java -Xmx256m ucar.grib.grib2.Grib2Indexer <grib2file>


here's a sample of the Grib 2 index:

0 0 0 0 2 100 60000.0 255 0.0 2009-02-03T21:00:00Z 0 -1113435711 
2702315 2702396
0 0 0 0 2 100 35000.0 255 0.0 2009-02-03T21:00:00Z 0 -1113435711 
2716166 2716247
0 0 0 0 2 100 10000.0 255 0.0 2009-02-03T21:00:00Z 0 -1113435711 
2729388 2729469

0 0 0 0 2 is temperature according to grib2 table grib2StdQuantities.xml,
6th # is level type and 7th the value of the level
and the last 2 numbers are the GDS and the PDS offsets into the grib
file.

There is java docs on Grib2GetData on the decoders page:

%java -Xmx256m ucar.grib.grib2.Grib2GetData <grib2file> GDSoffset PDSoffset

% java -Xmx256m ucar.grib.grib2.Grib2GetData data/grib2/ndfd.wmo 498193 498274 

The numbers are just samples and they will not work, you have to generate
your own index.

Robb...


Ticket Details
===================
Ticket ID: TBM-719686
Department: Support netCDF Decoders
Priority: Normal
Status: Open