Read a file line-by-line instead of read file into memory

Question

I´m having some trouble with reading a file line-by-line, instead of reading the the file into memory. As of right now, I\'m reading the file into memory, and it works perfect.

Answer 1

Is this right for you?

with open(filename, 'r') as f:
    data = f.readlines()

A = sum(float(line) for line in data)
B = sum(float(line)**2 for line in data)