From: Ben Strasser (strasser.ben_at_[hidden])
Date: 2006-08-29 14:09:18
Andy Little <andy <at> servocomm.freeserve.co.uk> writes:
> "Ben Strasser" <strasser.ben <at> googlemail.com> wrote in message
> news:loom.20060829T180704-945 <at> post.gmane.org...
> > In more complex situations you run accross the
> > problem that you can no longer
> > deduce the correct unit type. This is
> > also the reason why PQU (= Physical
> > Quantities Units) has introduced annomymous
> > units. However in what way does this
> > help? None that I can think of because in both situation (meaning non
> > printable units and annomymous units) the users
> > has to indicate how to print the units.
> FWIW, if this is a statement regarding Quan, then it is incorrect
Then please correct me. Somewhere in this
same thread you said:
> In the calculation:
> force * distance;
> The programmer might be dealing with a
> force acting at a moment, or the energy
> required to move an object. There is no
> way to tell from the calculation which.
> [...] , so the result is an
> anonymous quantity.
> One could apply various rules [...], but as I
> can't apply a rule easily to the above case,
> I opted to apply the same rule to every case
> of dimensionful multiplication and division,
> which was to return an anonymous quantity and
> leave it to the programmer to decide which
> quantity they were dealing with.
The way I understood this is that the library isn't
able to deduce what symbol corresponds to the units
so the user has to make a choice.
Did I misunderstand this or did I only get
the terminology wrong?
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