[QUANTITY] my fault for starting this up

[Patrick Dowler]

A couple of weeks ago, I emailed a UML diagram to ~10 people for comment.
Instead, we got a pretty ferocious email onslaught that eventually spilled 
over to the mailing list when 1 of those ~10 people unilaterally decided
to re-start the discussion on the list and thus get rid of the off-line 
discussion. That's water under the bridge at this point...

Just so everyone knows what started it up, I include for your perusal that
original UML diagram - without further comment since those were largely
ignored the first time around. I will point out the following: 

- there are no attributes, maning the model is incomplete and a point for
 disussing the relationship of the various parts... consider anything that is
 underspecified to be "open to discussion" or "possible to do" if you like

- color notation: only the pink bits are what I call "quantity"; the rest if 
  there for context only, which means that some parts are declared   
  "out-of-scope" by this diagram

- UML notation: closed triangle-head arrows mean generalisation, filled
  diamonds mean aggregation, arrows mean association; I have tried to use
  the least restrictive and most vague UML concepts possible 

So, I don't really expect or want more discussion on this since the list is 
now way into details best left for after one agrees on the basics. This is 
"the basics" as I see it after looking at many ideas. It is largely the same 
as the Unified Domain Model of Lemson, Dowler, and Banday (ADASS poster)
simply because that model drew from all the discussions and proposals over the 
summer. This is definitely NOT the CVO data model; I'm kind of sick of people
just dragging out their own model in responce to any attempt at consensus.
This IS a consensus of ideas brought forward from [Cambridge Interop, ADASS].

And yes - many things are not in there. Everything cannot be in there because 
many things are logically inconsistent with others. I don't care how many use 
cases you throw at it and how many requirements you specify, attempts to 
build on a logically inconsistent model are doomed to failure. 

OK, that's my rant for this week.

-- 
Patrick Dowler
Tel/Tél: (250) 363-6914                  | fax/télécopieur: (250) 363-0045
Canadian Astronomy Data Centre   | Centre canadien de donnees astronomiques
National Research Council Canada | Conseil national de recherches Canada
Government of Canada                  | Gouvernement du Canada
5071 West Saanich Road               | 5071, chemin West Saanich
Victoria, BC                                  | Victoria (C.-B.)
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