Should I use 'not x' or 'x == 0' to check to see if the result of a modulo operation is zero in python

Question

I really thought I'd have found something on this, and maybe it's out there and I'm missing it. If that's the case I apologize and I'll close the question.

I'm checking to see if a modulo operation returns a result of zero, and I was wondering which of these is "better" (more pythonic, faster, whatever):

if not count % mod OR if count % mod == 0

I guess I should clarify and say that I have a very good understanding of truthy and falsey values, I just wanted to know if there was a concrete reason to use one over the other. Especially considering this is always going to be a number (otherwise the % operator would throw a TypeError).

Answer 1

In general, the risk with using not x instead of x==0 is that you might match another kind of value that is also falsey (for instance, None or an empty list).

In this case, since x must be a number, it is safe to use not x to mean x==0. Use whichever seems more readable.

To me, the first version looks a little odd, because I expect the results of an arithmetic operation to be treated like a number, so I would prefer the second version. But falseyness is there for convenience, and there are lots of circumstances it makes sense to make use of it.