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From: Noah Stein (noah_at_[hidden])
Date: 2001-10-04 13:21:07

>(7) Suppose, instead, these qualifiers function as quantities. Then
>they represent a measurable attribute and so it would make sense to ask
>in what units they can be measured. I will therefore ask, "In what
>units can I measure the apple of something?"
>(8) At the moment, I can't satisfactorily answer these questions, and
>hence I tentatively conclude that the concept of qualifiers is
>orthogonal to the concepts of quantities and units. Can someone argue

I think you're barking up the right tree on this one. I think I have an
example that fits your view of the situation: a plane's airspeed vs.
groundspeed. Both are from the family of quantities Length<>/Time<>. Both
may be expressed in identical units. However, the two are semantically

I believe this is analogous to the situation for apples and oranges. Apples
and oranges, in one scenario, could be considered some sort of
Numeration<>/Price<>, as far as quantity is concerned. Any of a number of
unit choices could be made. Both apples and oranges live in the same
quantity/unit space; however, they are semantically different.

My $.02 is that the apples and oranges are a "qualifier" orthogonal to
quantities and units. If so, the next question is, should support for
qualifiers also be added to a quantity/unit library? Or is it so orthogonal
that a general-purpose qualifier library should be considered?

-- Noah

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