RE: Configuring GRIB tables in NetCDF

Tor,

Since this question has come up before, I created a web page at:

http://www.unidata.ucar.edu/software/netcdf-java/reference/GribTables.html


THis should answer all your questions.

RObb....






On Thu, 8 Oct 2009, Tor Christian Bekkvik wrote:

> Hi,
> The GribPDSParamTable.addParameterUserLookup call did not seem to help
> in my case; the resulting parameter names/units reported for my gribfile
> was still not affected.
> Probable cause:
> The addParameterUserLookup call only applies to GRIB-1
> (ucar.grib.grib1.GribPDSParamTable), while my gribfile triggered the
> GRIB-2 parser in NetCDF (from NetcdfDataset.openDataset(grib2file);)
>
>
>
> Questions:
> -1) Could Netcdf be instructed/hinted to prefer the GRIB-1 reader, when
> possible ?  (JGRIB, a grib-1 reader, was able to read my file)
>
> -2) Is there another way to configure GRIB tables (or parameter
> interpretation) in NetCDF which now would work for both GRIB-1 and
> GRIB-2 ?
>
>
>
> Thanks,
> -Tor C
>
> > -----Original Message-----
> > From: Robb Kambic [mailto:address@hidden]
> > Sent: 6. oktober 2009 21:02
> > To: Tor Christian Bekkvik
> > Cc: Gro Fonnes; netcdf-java; Kjell Røang
> > Subject: Re: Configuring GRIB tables in NetCDF
> >
> > On Tue, 6 Oct 2009, Tor Christian Bekkvik wrote:
> >
> > > Hi, I have some questions regarding GRIB table configuration:
> > >  
> > > 1) Is there a way to configure GRIBtables in NetCDF without
> > rebuilding
> > > grib-6.0.jar in ncSrc-4.0.zip!\lib\release\ ?
> > Tor,
> >
> > Yes, the following routine, in class GribPDSParamTable
> >
> > /**
> >     * Reads in the list of tables available and stores them.
> > Does not actually
> >     * open the parameter tables files, nor store the list of
> > parameters, but
> >     * just stores the file names of the parameter tables.
> >     * Parameters for a table are read in when the table is
> > requested (in the
> >     * getParameterTable method).
> >     *
> >     * @param userGribTabList string of userlookup file
> >     * @throws IOException on read error
> >     */
> >    public static void addParameterUserLookup(String userGribTabList)
> >
> >
> > There is a sample file with the grib jar called
> > userlookup.lst, it has the same syntax as tablelookup.lst.
> > If the table name begins with /, http:, or file: then it
> > looks for the file with the full path name, otherwise it
> > assumes the table is in the resource directory. The tables
> > are loaded according to site ID, subsite ID and table version
> > number that's obtained from the data file.  If you load a new
> > table with the same configuration as one in tablelookup.lst
> > file, your new configuration will over write the original
> > configuration.
> >
> >              GribPDSParamTable.addParameterUserLookup(
> > "/local/robb/trunk20090914/grib/resources/resources/grib/table
> > s/userlookup.lst");
> >
> > > 2) Where can I find sourcecode for grib-6.0.jar (or later
> > versions) ? 
> > > (the source will answer question 1, but is not included in
> > > ncSrc-4.0.zip)
> > >  
> > The source for the Grib decoder package is located on page:
> > http://www.unidata.ucar.edu/software/decoders/  unders downloads.
> >
> > The Grib package has just went under a major refactor to
> > implement the Ensemble data processing, so some APIs have be
> > deprecated. The deprecated APIs are going to be removed in a
> > future release so I suggest looking at the javaDocs for the changes.
> >
> > RObb...
> >
> >
> >
> >
> > >  
> > > We occasionally have gribfiles using gribtables not defined in
> > > grib*.jar. The only solution I currently know, is to unzip the
> > > grib*.jar file and modify gribtable definitions inside 
> > > \resources\grib\tables\tablelookup.lst.  (tablelookup.lst points to 
> > > *.tab files in the same directory) This is not very user
> > friendly, so 
> > > perhaps there is a java property or method call where you
> > can override some gribtable settings?
> > >  
> > >  
> > >  
> > > Thanks,
> > > Tor C Bekkvik
> > >  
> > > --
> > >
> > > Tor Christian Bekkvik
> > > Scientist
> > > Christian Michelsen Research AS
> > > Phone: +47 55 57 42 28
> > ==============================================================
> > =================
> > Robb Kambic                                Unidata Program Center
> > Software Engineer III                      Univ. Corp for
> > Atmospheric Research
> > address@hidden             WWW:
> > http://www.unidata.ucar.edu/
> > ==============================================================
> > =================
===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================