[Numpy-discussion] Home for pyhdf5io?

[Francesc Alted]

A Monday 25 May 2009 19:55:28 Eric Firing escrigué:
> >> If the aim is to come up with a method of saving numpy arrays that uses
> >> a standard protocol and does not introduce large dependencies, then
> >> could this be accomplished using netcdf instead of hdf5, specifically
> >> Roberto De Almeida's pupynere, which is already in scipy.io as
> >> netcdf.py?  Or does hdf5 have essential characteristics for this purpose
> >> that netcdf lacks?

After looking a bit at the code of pupynere, there is the next line:

assert magic == 'CDF', "Error: %s is not a valid NetCDF 3 file" % 
self.filename

So, the current version of pupynere is definitely for version 3 of NetCDF, not 
version 4.

> >>From what I understand, netCFD is based on on HDF5, at least as of the
> >
> > version 4 release.
>
> Netcdf4 is indeed built on hdf5, but netcdf3 is not, and netcdf3 format
> is likely to stick around for a *very* long time.  The netcdf4 library
> is backwards-compatible with netcdf3.

NetCDF4 is backwards-compatible with NetCDF3 just at API level, not the file 
format.  NetCDF3 has a much more simple format, and completely different from 
NetCDF4, which is based on HDF5.

Cheers,

-- 
Francesc Alted