utype for STC region in SIAP query response

[Norman Gray]

Doug, hello.

On 2011 Dec 19, at 01:33, Douglas Tody wrote:

>> It cannot be the UTYPE, if every data model uses a different UTYPE for a 
>> footprint.
> 
> Well this is the key point; yes we can standardize the core model and
> the UTYPE used for this purpose and they do not need to be different
> despite being included in different models.  Yes the namespace (dataset
> class or context) may be different for different classes of data, but
> the UTYPE, minus the namespace prefix defining the context where it
> used, can be the same and can be defined to meant the same thing.  This
> is how UTYPEs have historically been used up to now, and we can
> formalize this further in the UTYPE spec (hopefully without
> over-complicating the mechanism).

What would this achieve?

Say an application comes across a UTYPE

    foo:SpatialAxis.Coverage.Support.Area,

and suppose that the 'foo' namespace was standardised after the application itself was written, or since it was last updated.  Should that application treat this as a footprint?

I presume the answer is 'no'.  In that case, the application is stuck -- it has no idea what to do with this UTYPE, and cannot have any idea, until the application author reads the relevant standard and encodes it in an update of the application, which is then released and distributed.

If the answer is 'yes', because 'SpatialAxis.Coverage.Support.Area' is expected to mean the same thing everywhere, then it is clear that there is no point in having namespaces, and people should stop talking about them.

Best wishes,

Norman


-- 
Norman Gray  :  http://nxg.me.uk
SUPA School of Physics and Astronomy, University of Glasgow, UK