# [MATRIX-SIG] Re: int. division

**Charles G. Waldman
**
cgw@pgt.com

*Sat, 17 Jan 98 13:31 EST*

David J. C. Beach writes:
>
> Allow me to reiterate Paul Dubois's argument. Consider the code:
>
> x = i / j
>
> Now, suppose i=2 and j=4. Then x will be the integer, 2. Everybody agrees
> on this.
Well, not everybody. I would have 2/4 == 2.0 and 2//4 == 2
I think these are different mathematical operations; in one view,
division is an "inverse operation" to multiplication, just as
subtraction is the inverse operation to addition; just as
(-B) + A + B == A for all A and B
I expect
(1/B) * A*B == A for all nonzero B
[at least up to the limits of machine representation of real numbers]
In the other view, division is the solution of the equation
xa + r = b, r<b
for an integer x, given integers a and b.
Both of these are useful notions and I'm not proposing we take any
feature out of the language, I would simply acknowledge that these two
are not the same operation and distinguish them with different
symbols.
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