Sampling from a 6GB csv file without loading in Python

Question

I have a training data-set in CSV format of size 6 GB which I am required to analyze and implement machine learning on it. My system RAM is 6 GB so it is not possible for me to load the file in the memory. I need to perform random sampling and load the samples from the data-set. The number of samples may vary according to requirement. How to do this?

Answer 1

Something to start with:

with open('dataset.csv') as f:
    for line in f:
        sample_foo(line.split(","))

This will load only one line at a time in memory and not the whole file.