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Re: 950920: netCDF (is this a bug?)

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  • Subject: Re: 950920: netCDF (is this a bug?)
  • Date: Wed, 20 Sep 1995 13:56:04 -0600
>Organization: Air Force
>Keywords: 199509201853.AA19442 netCDF ncdiminq

Hi Stan,

> ncdiminq returns the correct size for all axes other than the
> unlimited axis, but returns 1 + correct size for the unlimited axis.
> That is, a file that ncdump reports as having "currently 144" entries
> on the time axis returns 145 to ncdiminq.

I can't duplicate this problem here, and it sounds puzzling since ncdump
just uses ncdiminq to get the size of the unlimited dimension that it
reports.  I just used "ncgen -b x.cdl" on the following small CDL file to
generate a netCDF file named "x.nc", then I ran ncdump on "x.nc" to verify
that the size of the unlimited dimension was 3, and finally I ran a small C
program to print the results of calling ncdiminq on this file.  The output
indicates that ncdiminq is in agreement that the size of the unlimited
dimension is 3.  I'd appreciate it if you could compile and link this C
program and let me know if it reports the size as something other than 3.

------------- x.cdl -----------------------------------------------------
netcdf x {
dimensions:
        t = unlimited ;
variables:
        float x(t);
data:
        x = 5, 10, 15;
}
------------- diminq.c --------------------------------------------------
#include <stdio.h>
#include <netcdf.h>

int main()
{
    int ncid, ndims, nvars, natts, uid;
    long usize;
       
    ncid = ncopen("x.nc", NC_NOWRITE);
    ncinquire(ncid, &ndims, &nvars, &natts, &uid); /* get id of unlim dim */
    ncdiminq(ncid, uid, (char *)0, &usize);        /* get size of unlim dim */
    printf("usize = %ld\n", usize);
    return 0;
}
-------------------------------------------------------------------------

Just for completeness, I ran the above test with the released version 2.3.2
of netCDF on a Sun SPARCstation10 under Solaris 2.4 using cc version
SC3.0.1, but I don't expect any of those details to be relevant to this
test.

______________________________________________________________________________

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