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[netCDFJava #QDJ-903556]: error when reading grib2 files

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  • Subject: [netCDFJava #QDJ-903556]: error when reading grib2 files
  • Date: Mon, 22 Feb 2010 06:36:37 -0700
Hi Ravi,

I'm going to let Robb answer your first question. I'll try to answer your 
second question.

Through the netCDF-java API, you would not access the GRIB records directly. 
The library maps the GRIB data into netCDF variables and other supporting GRIB 
information into netCDF attributes. All the data records for the same parameter 
on the same grid will be in a single 3-D (x,y,t) or 4-D (x,y,z,t) variable 
depending on the data. The grid information is available in several coordinate 
variables.

To get a better idea of what this looks like, you could take a look at your 
data in our ToolsUI applications that use the netCDF-Java library. ToolsUI is 
available as a jar or webstart from the netCDF-Java page 
(http://www.unidata.ucar.edu/software/netcdf-java/). In the "Feature Types" - 
"Grids" panel, enter your file location and hit return.

Ethan

> Ethan/Robb,
> 
> Thanks for your replies. I have 2 questiions:
> 
> 1. I tried out the option using Grib2Input :
> 
> RandomAccessFile random =  new 
> RandomAccessFile("C:\\temp\\ruc2.t00z.bgrb20f01.grib2","r");
> Grib2Input input = new Grib2Input(random);
> boolean success= input.scan(true, false);
> System.out.println("success= "+success);
> java.util.List<Grib2Record> records = input.getRecords();
> System.out.println("rec.size = "+records.size());
> 
> success is true, but rec.size is 0. Please suggest a solution.
> 
> 2. The other question I have is if I use NetcdfFile.open to read the grib file
> then after reading in the file how do you extract the grib from the NetcdfFile
> object. How do I get a reference to the different sections of the grib.
> 
> thanks,
> Ravi


Ticket Details
===================
Ticket ID: QDJ-903556
Department: Support netCDF Java
Priority: Normal
Status: Open