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[netCDFDecoders #ESX-118663]: Grib2Section4

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  • Subject: [netCDFDecoders #ESX-118663]: Grib2Section4
  • Date: Tue, 30 Mar 2010 09:51:46 -0600
Frédéric,

When you get the new release, this will be how to access Section 4 Satellite 
data.

try {
       NetcdfFile ncf = NetcdfFile.open( "GribFile" );
       System.out.println("Variable names are:");
       List<Variable> vars = ncf.getVariables();
       for (Variable var : vars) {
         System.out.println(var.getName());
       }

       Variable Water_temperature = ncf.findVariable("Water_temperature");
       GridVariable wt = (GridVariable) Water_temperature.getSPobject();
       Grib2GridTableLookup g2tl = ((Grib2GridTableLookup) wt.getLookup());
       int nb = g2tl.getNB();
       System.out.println("NB =" + g2tl.getNB());
       int[] series = g2tl.getSatelliteSeries();
       int[] sat = g2tl.getSatellite();
       int[] instru = g2tl.getSatelliteInstrument();
       float[] wave = g2tl.getSatelliteWave();
       for (int n = 0; n < nb; n++) {
         System.out.println(series[n] + " " + sat[n] +" " + instru[n]+" " + 
wave[n]);
       }
       ncf.close();
       System.out.println("Success");
     } catch (Exception exc) {
       exc.printStackTrace();
     }
   }

output:
Variable names are:
UnknownParameter_D10_C192_1
UnknownParameter_D10_C192_2
Water_temperature
time
Polar_Stereographic
y
x
NB =3
61 4 591 26.87
61 4 591 9.272
61 4 591 8.377

There is documentation about netcdf-java at: 
http://www.unidata.ucar.edu/software/netcdf-java/
under the heading of Related Documents and Feature Types.


After some discussion a decision was made not to make a difference between 
Unknown or Local Use parameters but to make the name more informative and 
unique. For Grib 2 the D stands for Discipline and C for Category. For example:

float   UnknownParameter_D10_C192_1             time,y,x        
UnknownParameter_D10_C192_1     1,3072,4096     Unknown


At this time, I don't know when the next 4.2 release will be made since it's 
still in testing.

Robb...


Ticket Details
===================
Ticket ID: ESX-118663
Department: Support netCDF Decoders
Priority: High
Status: Open