On Jul 25, 2006, at 18:48, Roy Williams wrote:
>
> My understanding:
> -- A code is also called an enumeration or a labeling or a
> classification. It is tied to a namespace. In the Hubble namespace,
> galaxies have codes Sa, Sb, SBa, E0 etc etc
> -- An ID is unique identifier for something that is strongly linked
> to a namespace. Within the Messier namespace, there are identifiers
> M31, M51, M87.
>
> -- A name is anything that identifies something, need not be
> unique. Thus a single galaxy can have several names, eq M87 and
> NGC4486 are different names for the same thing.
>
> -- A Title is a multi-word version of a name: "Center of Virgo
> cluster" would be a title for M87.
>
>
I think that the above sentences put together by Roy are a perfect example of how to write ucd descriptions. I would not agree though on the Hubble classification because the right ucd is in that case meta.code.class, and not just meta.code
P | meta.code | code is also called an
enumeration or a labeling
| of a flag. An example is
the PixFlags in the SIAP1.0
| standard, which is a flag
whose meaning is well
| understood within that
protocol.
P | meta.code.class | Classification, tide to a
namespace.
| In the Hubble namespace,
galaxies have codes
| Sa, Sb, SBa, E0 etc
P | meta.id | An ID is unique identifier
for something that
| is strongly linked to a
namespace. Within the
| Messier namespace, there
are identifiers M31, M51, M87
P | meta.title | A Title is a multi-word
version of a name:
| "Center of Virgo cluster"
would be a title for M87
P | meta.name | *** currently to be found
under meta.id, ***
| *** but probably it
deserves its own ucd? ***
It would be nice to extend the descriptions of all other ucds in a similar way, wouldn't it?
Alberto Received on 2006-07-26Z12:03:31