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[netCDF #YTY-788071]: netcdf 4 GB variable size questions

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  • Subject: [netCDF #YTY-788071]: netcdf 4 GB variable size questions
  • Date: Fri, 18 May 2007 08:07:31 -0600
> Hello--
> 
> I have a couple questions about the large variable size support in
> netCDF.  I would like to run a Weather Research and Forecasting (WRF)
> model simulation that will require individual variable arrays in
> excess of 4 GB.  I am aware that the standard release of netCDF_v3.6
> does not allow this.  Are there any modifications that will allow the
> model program to create a v3.6 netCDF file that will avoid this
> limitation?  Would you recommend that I upgrade to version 4.1 even
> though it is a beta version?
> 
> Thank you for your help.  Take care.
> 
> Sincerely,
> 
> Jason Otkin
> 
> 

Howdy Jason!

The best place to start with understanding the format limitations is:
http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/Large-File-Support.html

As you note, variables greater than 4 GiB are not permitted, even in 64-bit 
offset format (well, you can have *one* such variable).

That seems to leave netCDF-4-beta1 as your best option for now, though it is in 
beta state.

There is another extension of the netCDF classic format under discussion. If it 
ever occurs, it will once again ease the limitations of the netCDF format. But 
it is in the early stages of discussion right now.

Thanks,

Ed

Ticket Details
===================
Ticket ID: YTY-788071
Department: Support netCDF
Priority: Normal
Status: Closed