[nvo-techwg] Referencing in XML for the IVO

[Arnold Rots]

Appended is something that will work (and that I showed at the team
meeting in abbreviated form).  It has URLs instead of IVO identifiers
but that's a detail.

  - Arnold

Roy Williams wrote:
> Arnold
> 
> Please excuse me, my schema expertise is not as good as yours, so I 
> attempt to sketch some examples.
> 
> What I want is to say, for example:
> <AstroCoordSystem
> 	ID="FK5-UTC-TOPO"
> 	xlink:href="ivo://stc.ivoa.net/FK5-UTC-TOPO">
> so that any of the VO registries can tell me where to find the precise 
> definition of this coordinate system, should that be required.
> 
> Another example would be for observatory location. I would want to say:
> <ObservatoryLocation
> 	ID="Palomar"
> 	xlink:href="ivo://nvo.caltech.edu/observatories/Palomar">
> 
> Is this what you envision?
> Roy
> 
> California Institute of Technology
> 626 395 3670
> 
--------------------------------------------------------------------------
Arnold H. Rots                                Chandra X-ray Science Center
Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
60 Garden Street, MS 67                              fax:  +1 617 495 7356
Cambridge, MA 02138                             arots at head.cfa.harvard.edu
USA                                     http://hea-www.harvard.edu/~arots/
--------------------------------------------------------------------------

<?xml version="1.0" encoding="UTF-8"?>
<ObsDataLocation xmlns="http://www.ivoa.net/xml/STC/stc-v1.23.xsd"
    xmlns:crd="http://www.ivoa.net/xml/STC/STCcoords/v1.23"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:xlink="http://www.w3.org/1999/xlink"
    xsi:schemaLocation="http://www.ivoa.net/xml/STC/stc-v1.23.xsd
    http://hea-www.harvard.edu/~arots/nvometa/v1.23/stc-v1.23.xsd">

  <ObservatoryLocation id="MyObservatory" xlink:type="simple"
       xlink:href="http://www.ivoa.net/xml/STC/STClib/Observatories.xml#MyObservatory"/>

  <ObservationLocation>
    <AstroCoordSystem id="UTC-FK5-TOPO" xlink:type="simple"
       xlink:href="http://www.ivoa.net/xml/STC/STClib/AstroCoordSystems.xml#UTC-FK5-TOPO"/>
    <crd:AstroCoords coord_system_id="UTC-FK5-TOPO">
      <crd:Time unit="s">
        <crd:TimeInstant>
          <crd:ISOTime>2005-04-15T23:59:59</crd:ISOTime>
        </crd:TimeInstant>
        <crd:Error>2</crd:Error>
      </crd:Time>
      <crd:Position2D unit="deg">
        <crd:Value2>141 69</crd:Value2>
        <crd:Error2Radius>0.05</crd:Error2Radius>
      </crd:Position2D>
    </crd:AstroCoords>
  </ObservationLocation>
</ObsDataLocation>