I want to implement Logisitic regression from scratch in python. Following are the functions in it:

1. sigmoid
2. cost
3. fminunc
4. Evaluating Logistic regression

I would like to know, what would be a great start to this to start from scratch in python. Any guidance on how and what would be good. I know the theory of those functions but looking for a better pythonic answer.

I used octave and I got it all right but dont know how to start in python as OCtave already has those packages setup to do the work.