Relationship between Q and STC (Was: Re: [QUANTITY] Data Model for Quantity v0.5

[Brian Thomas]

On Monday 10 May 2004 01:28 pm, David Berry wrote:
> Alberto,
>
> > c.- What's the relationship of Q and STC?
> > How are quantities going to use  STC ?
>
> An STC document is exactly equivalent to a Frame, and could be seen as a
> serialisation of a Frame. There is one complication though -  in addition
> to defining a coordinate system, an STC document can also specify a
> particular region within that coordinate system. Currently the Q document
> does not have a model for a Region. But it could have - I'm adding one to
> the AST library as we speak (when and as I get time off from other
> things).

	David, 

	I sort of agree, but STC (I think) oversteps into domain of Q for specification
	of coordinates, and the Q does it better; This part should be in the Q. Furthermore, 
	the ST part of "STC" can be realized as a quantity.

	Finally, I think that "Region" should be a separate namespace and not in the Q.
	I think thats how the stc_test stuff I posted has done it..

	If I can get the time, I'll try to write up some English to explain the proposal better.


	Regards,


	=b.t.

>
> David
>
> ---------------------------------------------------------------------- Dr
> David S. Berry (dsb at ast.man.ac.uk)
>
> STARLINK project		 |	Centre for Astrophysics
> (http://www.starlink.ac.uk/)	 |	University of Central Lancashire
> Rutherford Appleton Laboratory	 |	PRESTON
> DIDCOT				 |	United Kingdom
> United Kingdom			 |	PR1 2HE
> OX11 0QX                                Tel. 01772 893733
>                                              01257 273192

-- 

  * Dr. Brian Thomas 

  * Dept of Astronomy/University of Maryland-College Park 
  * Code 630.1/Goddard Space Flight Center-NASA

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