Remove usage of numpy and use builtin math when possible

[silvanocerza]

Numpy is an heavy library to import and we overuse it all around the codebase.

We should remove it and fallback to use builtin math whenever possible to speed up import speed.

[vaishjah3]

Sorry for the naive question, but I am really new to this. So, do you expect numpy functions to be converted to math functions in the code wherever possible?

[silvanocerza]

@vaishjah3 that's the idea. 👍