STC documents and schemas

[Arnold Rots]

I have posted revised STC schemas and documentation.
To simplify matters, the schemas assume that they coexist in the same
working directory, but uncommenting the alternative location will
work, too.

Quick summary:
All polymorphisms are implemented as substitution groups.
Units are attributes of the Coordinate elements (not the individual
components).
There are generalized CoordSys and Coords elements, with
AstroCoordSystem and AstroCoords the inherited classes, specifically
for STC.
AstroCoordSys may actually point to an instantiation that lives in a URL.


http://hea-www.harvard.edu/~arots/nvometa/stc.xsd
    STC main schema

http://hea-www.harvard.edu/~arots/nvometa/coords.xsd
    STC coordinates schema

http://hea-www.harvard.edu/~arots/nvometa/region.xsd
    STC region schema

http://hea-www.harvard.edu/~arots/nvometa/AstroCoordSystem.xml
    Example XML document with standard AstroCoordSystem element
    (to be used as reference substitution)

http://hea-www.harvard.edu/~arots/nvometa/STC.pdf
    Working draft

http://hea-www.harvard.edu/~arots/nvometa/STC_UML.pdf
    UML diagrams (also include in working draft)


--------------------------------------------------------------------------
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/
--------------------------------------------------------------------------