Hi Nan,
> I agree with Roy that CF should be the default namespace in a
> CF compliant file...
What does that mean?
Until we agree on the meaning and mechanism of namespace-handling within
CF-compliant files and software, I fear that such statements do not
provide much guidance at the practical, implementation level.
For example, in a CF-compliant netcdf file it's possible to have named
identifiers from the netCDF ontology (e.g. _FillValue), from the COARDS
ontology (e.g. missing_value), from the CF ontology (e.g.
standard_name), and from any number of additional ontologies that one
happens to reference (SDN, ISOxxx, Dublin Core, etc, etc). I don't
believe it makes sense to bundle them all, by default, into some
notional CF namespace.
Perhaps the only solution lies in using netCDF-4's existing namespacing
mechanism, namely groups (which idea has been proposed before). I
suspect this too will have it's adherents and detractors!
> ... and that this problem belongs to groups that are writing
extensions.
Do you mean software extensions, or metadata extensions (profiles)?
Also, if you hand off responsibility to other groups (whatever and
wherever they may be) would we not end up with a myriad of incompatible
solutions?
> Should more of these community conventions be added to CF?
> I'm sure there are SDN and NCADD (data discovery) attributes
> that would be helpful to some CF users; it would be awfully
> nice to have a list of already-defined attributes - in one
> place - to choose from when putting together a CF-based spec
> for a project.
This would seem to be a good candidate, IMO:
http://www.unidata.ucar.edu/software/netcdf/conventions.html
Regards,
Phil
Received on Tue Jan 29 2013 - 07:19:21 GMT
