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[netCDF #ZYF-261630]: nccopy (hdf?) error when a dimension name and a variable name are the same

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  • Subject: [netCDF #ZYF-261630]: nccopy (hdf?) error when a dimension name and a variable name are the same
  • Date: Wed, 20 Jul 2016 11:24:13 -0600
Hello,

Thanks for reporting this issue; there shouldn't be a problem with what you're 
trying to do.

I've opened an issue at our GitHub repository, which you can view/follow here:

* https://github.com/Unidata/netcdf-c/issues/295

I will take a look at the failure in nccopy and see if I can figure out what is 
going on.

Thanks!

-Ward

> If a dimension name and a variable name are the same, nccopy will generate an 
> error.
> This does not appear to be a problem with netcdf-4/hdf files we are 
> generating programmatically.
> 
> 
> 
> We started to observe the following error with
> hdf5-1.8.10-linux-x86_64
> netcdf-4.3.3.1
> 
> and found it is still present when we tested with:
> hdf5-1.10.0-patch1-linux-centos6-x86_64-gcc447-shared
> netcdf-4.4.1
> 
> (prior to netcdf-4.3.3.1 we were just netcdf-3, so I can't comment on when
> the problem may have started)
> 
> 
> 
> Given the following CDL (afile.cdl):
> 
> 
> netcdf afile {
> dimensions:
> elapsed_time = UNLIMITED ; // (1 currently)
> aName = 4 ;
> variables:
> double aName(elapsed_time, aName) ;
> 
> // global attributes:
> data:
> 
> 
> aName =
> 1, 2, 3, 4 ;
> 
> }
> 
> 
> ncgen -4 -o afile.nc afile.cdl
> 
> nccopy -4 afile.nc afile2.nc
> 
> generates the following error:
> 
> NetCDF: Index exceeds dimension bound
> Location: file nccopy.c; line 1045
> 
> 
> if the cdl is more complicated, it still generates an error, but the error
> changes to:
> 
> NetCDF: HDF error
> Location: file nccopy.c; line 1045
> 
> 
> 
> If instead of generating a netcdf-4 file with ncgen, we back down to netcdf-3,
> using nccopy to create a netcdf-4 version of the file will work. However 
> copying that
> netcdf-4 file will (not surprisingly) generate the error.
> 
> All of this was discovered when we wanted to retroactively compress existing 
> netcdf-4
> files via nccopy.
> 
> I did take a quick look at nccopy, but was not able to see anything obvious 
> about why
> nccopy would be having a problem.  I went back a couple of years in the 
> netcdf support
> archive and didn't see anything that would appear to be relevant to this.
> 
> --
> 
> Robert M. Shectman
> 
> National Atmospheric Release Advisory Center (NARAC)
> Lawrence Livermore National Laboratory
> 
> address@hidden
> (925)423-6714
> 
> 


Ticket Details
===================
Ticket ID: ZYF-261630
Department: Support netCDF
Priority: Normal
Status: Closed
===================
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