In Python, what is a good way to round towards zero in integer division?

Question

1/2

gives

0

as it should. However,

-1/2

gives

-1

Answer 1

Try this. Only works for numbers greater than -1

import math

x = .5
y = -.5

print math.floor(math.fabs(x))
>> 0

print math.floor(math.fabs(y))
>> 0

Answer 2

Correct code to do this is, in my opinion, too obscure to write as a 1-liner. So I'd put it in a function, like:

def int0div(a, b):
    q = a // b
    if q < 0 and b*q != a:
        q += 1
    return q

Good features: it works for any size of int, doesn't make any adjustment to the raw (a//b) result unless necessary, only does one division (% also does a division under the covers), and doesn't create any integers larger than the inputs. Those may or may not matter in your application; they become more important (for speed) if you use "big" integers.