Numeric coercions

Vlastimil Brom vlastimil.brom at
Sun Jul 7 10:15:27 CEST 2013

2013/7/7 Steven D'Aprano <steve+comp.lang.python at>:
> I sometimes find myself needing to promote[1] arbitrary numbers
> (Decimals, Fractions, ints) to floats. E.g. I might say:
> numbers = [float(num) for num in numbers]
> or if you prefer:
> numbers = map(float, numbers)
> The problem with this is that if a string somehow gets into the original
> numbers, it will silently be converted to a float when I actually want a
> TypeError. So I want something like this:
> --
> Steven
> --
I guess, a naive approach like

numbers = [float(num+0) for num in numbers]

wouldn't satisfy the performance requirements, right?


More information about the Python-list mailing list