[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[netCDFJava #QVA-393299]: Problem reading HDF4 and HDF5 files

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: [netCDFJava #QVA-393299]: Problem reading HDF4 and HDF5 files
  • Date: Wed, 14 Jan 2015 16:33:45 -0700
Hi Antonio:

In 4.2 we tried to allow blanks in the group names. this caused too much 
trouble, so we replace them with "_", i guess starting in 4.3. 
So the correct name is Data_Fields not Data Fields
We try to stay backwards compatible, but sometimes we cant, sorry for the 
breakage.

The correct thing to do is to get a listing of variables in the file, to see 
what the valid variable names are.

John



> Hello,
> 
> Since Java-NetCDFversion 4.3 there is a problem in finding variable
> inside an HDF4 or HDF5 file.
> 
> The follwing code works fine for JavaNetCDF 4.2 but variable=null for
> JavaNetCDF version 4.3 and 4.5
> 
> String path = groupInFile + SUBDATASETS_GROUP_DELIMITER +
> nameInGroup; // == "/HDFEOS/GRIDS/ColumnAmountNO2/Data
> Fields/ColumnAmountNO2TropCloudScreened"
> Variable findVariable = file.findVariable(path); // returns "null"
> while in JavaNetCDF version 4.2 it is OK
> 
> where "file" is "NetcdfFile"
> 
> The HDF5 file used in this code can be found here:
> https://www.dropbox.com/s/z6olxfoocx1ul8x/OMI-Aura_L3-OMNO2d_2004m1001_v003-2013m0109t110353.he5?dl=0
> 
> Sorry for posting on several mailing lists since I am not sure which
> is most appropriate.
> 
> With kind regards,
> Antonio
> 
> 

Ticket Details
===================
Ticket ID: QVA-393299
Department: Support netCDF Java
Priority: Normal
Status: Closed