Re: [boost] Re: SIunits and quantity library concerns

From: Kevin Lynch (krlynch_at_[hidden])
Date: 2001-10-05 13:55:02

Kevin Lynch wrote:
> > I disagree. If we develop tags, then I think these things have an SI
> > unit of Amount<>, which can be measured in units of moles, or
> > individual items. Anything can be measured in this units, not just the
> > atoms and molecules of chemistry.
> >
> > And as is very natural with other types of SI unit Amount<>, the
> > conversion factors are important. Treating it this way may make some of
> > these things clearer.
> >
> > George Heintzelman
> > georgeh_at_[hidden]
> >
> 
> Alright, I might be able to buy that argument.  Like I said, I'm not
> sure what I'm missing just yet, and this may be one of those things.
> Just to make sure that I understand, you're saying that "number of
> things" has is a quantity of type Amount<>, and the unit here is "number
> of cartons".  So it is not "unitless", but Amount<> is still
> "dimensionless" since it is a counting "unit".
> 

Let me try again.  I should have said:

Just to make sure that I understand, you're saying that "number of
things" has is a quantity of type Amount<>, and the unit here is
"amount" or "mole".  Then, "9 cartons of apples"  would have

quantity = 9
unit = "amount"
unit tag = "carton"
(unit tag) tag = "apple"

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