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Re: 20040818: Very large netCDF files

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  • Subject: Re: 20040818: Very large netCDF files
  • Date: 17 Aug 2004 13:26:07 -0600
Howdy Tom,

I'm Ed, a NetCDF programmer...

I would be very interested in which architecture you built netcdf on.

Also are you using the NC_64BIT_OFFSET in the nc_create when you try
to create large files?

Thanks,

Ed


Russ Rew <address@hidden> writes:

> >To: address@hidden
> >From: "Tom Black" <address@hidden>
> >Subject: Very large netCDF files
> >Organization: NOAA/NCEP
> >Keywords: 200408171812.i7HICaaW023852 netCDF large file
> 
> Hi Tom,
> 
> > Here at NCEP we are hitting major roadblock.  We need to generate large 
> > netCDF files for very large domains as input for our forecast models.  
> > However in our first attempts we are stopped by that fact that the 
> > netCDF files which are certainly over 2 gigabytes long are not created 
> > properly.  I tried installing your beta version of netCDF3.6.0 since it 
> > was our understanding that the 2Gb limit was no longer an issue with 
> > that version.  Although the installation appeared to go okay, the same 
> > problem remains.  When I back off to a smaller integration domain for 
> > which smaller netCDF files are produced, then there is no problem either 
> > with 3.5.0 or 3.6.0.  Can you help us with information that will permit 
> > us to write netCDF files that are well over 2Gb in length?  Thank you 
> > very much.
> 
> Yes, We are *very* interested in the problems you are encountering
> with the 3.6.0 beta release.  We have been generating test cases that
> work as intended, but we would like to make sure the library works for
> realistic cases that may uncover bugs not revealed by our current
> tests.
> 
> If you could make available an example of code that demonstrates a
> problem with accessing large netCDF files that we can reproduce and
> debug, we would be very grateful!
> 
> --Russ