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[netCDF #YYS-526547]: netCDF file limitation?

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  • Subject: [netCDF #YYS-526547]: netCDF file limitation?
  • Date: Fri, 19 Jun 2009 10:03:51 -0600
Hi Mingkui,

> I want to know if there is a 2G limitation for creating a netCDF file
> by ncgen, version 3.6.3, even version 4?  I am creating a netCDF file
> with 3-D(30x1100x1400) variables by ncgen. When I make the file has 6
> variables, it is ok, and the file size is about 2.1G. But when I want
> to add one more 3-D variable, I get such error message:
> 
> ncgen: NetCDF: One or more variable sizes violate format constraints

No, you just have to tell ncgen to use the 64-bit offset variant of
the file format (indicated with a "-k 2" option), for example:

  $ ncgen -k2 -b rst1.cdl
  $ ls -l rst1.nc
  -rw-r--r--   1 russ     ustaff   2587200404 Jun 19 09:59 rst1.nc

The "-k kind" options for ncgen are documented in the man page
documentation:

     ncgen  [-b]  [-c]  [-f]  [-k  kind_of_file]  [-x]  [-n]  [-o
          netcdf_filename] input_file

...

     -k kind_of_file

          Using -k2 or -k "64-bit offset" specifies that generat-
          ed  file  (or  program)  should use version 2 of format
          that employs 64-bit file offsets.  The  default  is  to
          use  version  1  ("classic")  format  with  32-bit file
          offsets, although this limits the size  of  the  netCDF
          file,  variables, and records to the sizes supported by
          the classic format.  (NetCDF-4 will support  additional
          kinds of netCDF files, "netCDF-4" and "netCDF-4 classic
          model".)  Note: -v is also accepted to  mean  the  same
          thing  as -k for backward compatibility, but -k is pre-
          ferred, to match the corresponding ncdump option.

--Russ

> Here is the content of my test case .cdl file:
> 
> netcdf rst1 {
> dimensions:
> xi = 1400 ;
> eta = 1100 ;
> s = 30 ;
> variables:
> double a(s, eta, xi) ;
> double b(s, eta, xi) ;
> double c(s, eta, xi) ;
> double d(s, eta, xi) ;
> double e(s, eta, xi) ;
> double f(s, eta, xi) ;
> double g(s, eta, xi) ;
> }

Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: YYS-526547
Department: Support netCDF
Priority: Normal
Status: Closed