Warnings in tests

[MaceKuailv]

Sometimes there is devide by zero warnings in the tests, which is as intended. I will take a closer look at all of them and silence them with care.

[MaceKuailv]

@malmans2 If the code is running correctly, there should be divide by zero warnings from place to place. Do you think it is acceptable to silence all of them in the tests?

[malmans2]

I would avoid it. You have a few of that warnings, but they are not that many.
Use assert as much as possible for warnings that you fully understand, filter the other warnings but not globally (e.g., use the decorator).

Assert is better because if you expect the warning but it won't show up in the future, you know that something is not right. And if you'll get the zero division warning in a function where you don't expect it, you'll notice right away.

[MaceKuailv]

close with #58