Can math.atan2 return INF?

Gregory Ewing greg.ewing at canterbury.ac.nz
Tue Jun 28 02:12:17 EDT 2016


Rustom Mody wrote:
> I said that for the Haskell list [0..]
> 
> [0..] ++ [-1] == [0..]
> 
> He said (in effect) yes that -1 would not be detectable but its still there!

The code to generate it is there, but it will never
be executed, so the compiler is entitled to optimise
it away. :-)

He may have a point though. There are avenues of
mathematics where people think about objects such
as "all the natural numbers, followed by -42", and
consider that to be something different from just
"all the natural numbers".

So, a mathematician would probably say they're not
equal. A scientist would say they may or may not be
equal, but the difference is not testable.

An engineer would say "Lessee, 0, 1, 2, 3, 4, 5,
6, 7... yep, they're equal to within measurement
error."

-- 
Greg


More information about the Python-list mailing list