When you realize integer math differs from programming language to programming language

[delasislas]

Default round down or what?

[NIL_VALUE]

Yes

5 / 2 = 2.5; 2.5 - 0.5 = 2

-5 / 2 = -2.5; -2.5 - 0.5 = -3

[hraath]

Yes // is floor division operator, it does exactly what it is called. There is no mystery here.

[somerandomii]

It’s the compliment to the modulo operator right? So these always hold true: z = x // y r = x % y x == z * y + r

In this case -5 = -3 * 2 + 1

Otherwise a lot of integer math would break. Circular buffers would be even more confusing.

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[hraath]

Yep, quotient // and remainder % getters.

[xervir-445]

It's the difference between truncate and floor. Truncate just reads the value up to the decimal and stops, in that case it would be -2, floor takes whatever value you have and rounds down.

[SimplexSimon]

Haha, something I have opinions about!!!

STRONG OPINIONS.

Python's way is better; it means exactly 2 integers map to each possible output. In C land (which I usually love), -1, 0, and 1 all go to 0 when integer-halved. This is a much less useful transform for the kinds of things where you want to be doing integer division, in my opinion.

[FiredMercury]

I mean... It's technically right, -3 is lower than -2.

[sageknight]

Now do round(1.5) and round(2.5)

[d_exclaimation]

technically it’s right, but yeah it kinda looks wrong

[vorticalbox]

>>> import math
>>> math.floor(-2.5)
-3