fix integer check

[yascho]

Hi, calling check_all_int [1] with floating-point numbers < 1, e.g.

check_all_int([0.5])

results in

ZeroDivisionError: float modulo

Reason is mainly that int(0.5)=0 and then i % int(i) is undefined.

This happens for example when solving 0-1-knapsack with profits, weights or capacity < 1 (method="mt1r") [2]. Note that we don't have to check if the values are integers if the method is already "mt1r", so changing check_all_int is just a quick-fix and not a code refactoring.

Hope it helps, thank you!

[1] https://github.com/jmyrberg/mknapsack/blob/master/mknapsack/_utils.py#L21
[2] https://github.com/jmyrberg/mknapsack/blob/master/mknapsack/_single.py#L95

[jmyrberg]

Hi, and thanks for the PR! Could you still add a test case for this, i.e. single 0-1 problem that doesn’t pass the old way, but would pass with the new code?