PEP 238 (revised)

Chris Barker chrishbarker at home.net
Fri Jul 27 21:27:44 CEST 2001


> Semantics of Floor Division
> 
>     Floor division will be implemented in all the Python numeric
>     types, and will have the semantics of
> 
>         a // b == floor(a/b)
> 
>     except that the type of a//b will be the type a and b will be
>     coerced into.  Specifically, if a and b are of the same type, a//b
>     will be of that type too.

so:

3//2 == 1

3.0//2.0 == 1.0

3.0//2 == 1.0

so if I want to use the result as an index, I'll need to use:

int(x/y)

kind of like I now use:

int(floor(x/y))

What I don't get, is why // couldn't return an integer always? It will
always have an integral value. I suppose one problem is that the range
of integers that a float (C double) can handle is larger than a 32 bit
integer can hold. This could be solved in the future with int/long
inification, what will be the behaviour then?

-Chris



-- 
Christopher Barker,
Ph.D.                                                           
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