Re: [netcdfgroup] NetCDF-3 file format changes

• To: John Caron <caron@xxxxxxxxxxxxxxxx>
• Subject: Re: [netcdfgroup] NetCDF-3 file format changes
• From: Mario Emmenlauer <mario@xxxxxxxxxxxxx>
• Date: Wed, 27 Feb 2008 00:52:33 +0100

Hi,

John Caron wrote:

Joe Sirott wrote:

There's still a limit on variable sizes with netcdf 3.6 of 4 GB (though
not 2GB as I mentioned):

http://www.unidata.ucar.edu/software/netcdf/faq-lfs.html#Large%20File%20Support10

And I'm also guessing (John C: feel free to correct me) that it's 2GB in
Java due to the lack of unsigned integers.

thats a good question. we do support Large Files, and should not be 
artificially limited to 2 Gb.
However, I dont think Ive actually tested writing these. If you want to test 
and theres a problem, I
will fix.

I have been using NetCDF Java for some time now, and could never (i.e. not
with versions 2.2.18 to 2.2.22) get it to write variables larger than 2 or
4GB (I do not recall the precise number).

And the available version of NetcdfFileWriteable.addDimension() uses 'int'
to set the size. That essentially makes it impossible to have 3D datasets
of <= 32 bit depth with more than 4GB. See
http://www.unidata.ucar.edu/software/netcdf-java/v2.2.22/javadoc/ucar/nc2/NetcdfFileWriteable.html
   public Dimension addDimension(java.lang.String dimName, int length)
for reference.

Cheers,

   Mario

• References:
  • [netcdfgroup] NetCDF-3 file format changes
    • From: Joe Sirott
  • Re: [netcdfgroup] NetCDF-3 file format changes
    • From: Roy Mendelssohn
  • Re: [netcdfgroup] NetCDF-3 file format changes
    • From: Joe Sirott
  • Re: [netcdfgroup] NetCDF-3 file format changes
    • From: John Caron