Expressing 2- and 3-D coordinates

[Patrick Dowler]

On 19.12.2005 15:55, Rob Seaman wrote:
> On Dec 19, 2005, at 2:27 PM, Arnold Rots wrote:
> 
> > STC for the time being converts to enumerating the vector  
> > components as in my first message, and may change back to list  
> > types when list support is firmly there.  [...[  The STC schemata  
> > will be adapted accordingly.

Have just been lurking on this issue, so I will just say that I think
that if this means tagging the components (pretty sure it does) then
I think that's good for basic coord (or any structured value) support.

The xsd:list construct looks like an optimisation when used in places
where the length of the list is fixed (coords, eg). I think these optimizations 
will be necessary at some point, but I don't think the should ever replace
a standard representation.

One would naturally use polymorphism to make an optimized implementation
of a class that could be used in place of a simpler construct. I don't know
how well such a thing can be done in XML schema - specifically, can you
(eventually) allow for two different representations without making something
optional?


-- 
Patrick Dowler
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