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Re: netCDF and HDF

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  • Subject: Re: netCDF and HDF
  • Date: Tue, 07 Mar 1995 21:10:58 -0700
> Organization: IBM
> Keywords: 199503080247.AA24598

Lloyd,

> Let me ask another question about converting between HDF-encoded netCDFs
> and XDR netCDFs.  If I recall ncdump produces to stdout what would be
> suitable for input to ncgen.  Could I then pipe the output from the mfhdf
> ncdump to the Unidata ncgen and get an XDR-encoded netCDF that our current
> code would read?  Granted this operation would not be efficient, given
> conversion to ASCII and scribbling over a pipe.  But would it be a crude
> workaround for these folks that I working with?

Yes, that's a clever way to convert an HDF-encoded netCDF file to an
XDR-encoded netCDF file.  The invocation would be:

   HDFncdump file.hdf | ncgen -o file.nc -

where "file.hdf" is the input HDF-encoded netCDF file, and "file.nc" is the
output equivalent netCDF file.

It's a little slow, but it seems to work fine, except that the default
precision that ncdump uses to output floating-point and double-precision
values (6 and 15 significant digits) may lose some precision in the output
file.  There are ncdump flags that permit specifying the precision used.

--Russ