[Tutor] from __future__ import division

Steve Willoughby steve at alchemy.com
Sun Mar 23 19:51:38 CET 2008

```Dinesh B Vadhia wrote:
> I spent fruitless hours trying to get a (normal) division x/y to work and then saw that you have to declare:

normal division x/y works just as expected, with one caveat: remember
that if you divide two *integer* values, you will get an *integer*
division operation yielding an *integer* result.  So:

1.0 / 2.0 --> 0.5
1.0 / 2   --> 0.5
1 / 2.0   --> 0.5
1 / 2     --> 0

So if you make sure at least one operand is a real number you'll get
a real result.  This is now division works in many programming languages
including C and C++.

In the future, Python will switch to always yielding a real result,
and to force an integer division operation you use the special "//"
integer division operator.  If you want that behavior now, just
import that "from the future":

from __future__ import division

now:

1 / 2 --> 0.5
4 / 2 --> 2.0
1 // 2 --> 0
4 // 2 --> 2

HTH HAND

>> from __future__ import division
>
> .. at the top of a module file.  What is this all about?
>
> Dinesh
>
>
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> http://mail.python.org/mailman/listinfo/tutor

```