Expressing 2- and 3-D coordinates

[Ed Shaya]

It makes little difference for Value2. Either way is fine with me.   But 
once people notice that if they use the correct parser arrays are 
possible in XML, and then we can move generally to having data arrays of 
length appropriate for astronomy.  VOTable should be composed of  
xsd:list elements so that one is not repeating <td> tens of millions of 
times.

I might note that ChemML has had XML arrays since 1999, even before 
xsd:list.  The chemists realized that arrays
are so important that standard XML parsers needed to be enhanced to 
include them.  Now this is no longer necessary.
http://www-ece.engr.ucf.edu/~jza/classes/4781/XML/XML.html  (search for 
array).


Ed


Matthew Graham wrote:

> Hi,
>
> Just to add my tuppence worth here: the bottom line really has to be 
> that the XML representation is implementable in a platform-independent 
> way. You just have to go with the lowest common denominator: it really 
> matters not one jot if
>
> <Value2> 149.60 23.5</Value2>
>
> is the most elegant representation but cannot be parsed properly by a 
> sizeable fraction of our systems, you just have to use
>
> <Value2>
>  <C1>149.60</C1>
>  <C2>23.5</C2>
> </Value2>
>
> instead. The moment we start mandating a particular infrastructure to 
> support our XML, we sound the death knell from the user community.
>
>       Cheers,
>
>       Matthew