> > I guess you could call the associative law of multiplication "dumb
> > luck", but most mathematicians will consider that hate speech.
>
> My apologies for not understanding your example. The counter
> example I had in my head, and should have written down,
> was something like:
>
> 15mpg * 7l == how many miles?

Using pint:

In [76]: U = pint.UnitRegistry()

In [77]: (15 * U.miles / U.gallons * 7 * U.liter).to('miles')
Out[77]: 27.7380654976056 <Unit('mile')>

A bit verbose, perhaps, but to me clear, and the operator precedence rules seem to "just work".

And it you want it a tad less verbose, you can give some of those units names:

In [78]: mpg = U.miles / U.gallons
In [79]: l = U.liter

In [80]: (15 * mpg * 7 * l).to('miles')
Out[80]: 27.7380654976056 <Unit('mile')>

My question for the folks that want units built in to Python is "what's so hard about that?

Ricky wrote:

"Python is so painful to use for units I've actually avoided it,"

Really? have you tried pint? or anything else? what is so painful about this?

-CHB

Christopher Barker, PhD (Chris)

Python Language Consulting
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