[QUANTITY]: gather requirements for quantity model

[Patrick Dowler]

On Tuesday 28 October 2003 13:29, Brian Thomas wrote:
> On Tuesday 28 October 2003 03:34 pm, Patrick Dowler wrote:
> > This is NOT a difficult problem as long as we refrain from redefining
> > the words of the the english language willy-nilly, ie the word Quantity.
> > It has a fairly well focused and accepted meaning in the world of computer
> > science and we would be fools to stray from the actual meaning of the
> > word.
>
> 	Well, we arent just doing computer science though. 

At some low levels we are just doing CS; if we are not then we are
totally screwed because we are mixing domain-specific knowlegde
and concepts with basic fundamentals of math and comp sci. That
path leads to disaster.

> As the very
> least, we are
> 	talking about "physical" quantities like "flux", "wavelength" in
> addition to
> 	CS quantities like "set" or "value" or "datacube".

The point is that in CS "set" and "datacube" are NOT quantities. They
are containers. 

As for the physical quantities "flux" and "wavelength", the SI site uses the 
term "quantity in the general sense" for such things and it is confusing in 
light of a perfectly good word in the english language for exactly what they 
meant: phenomenon. Now, we could follow SI to the letter and have a class
like QuantityInTheGeneralSense, but I think everyone would agree that 
it is stupid to use a phrase when a word suffices.

-- 
Patrick Dowler
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