Generate a Histogram from a CSV

csv_to_histogram.py

#! /usr/bin/python

from matplotlib import pyplot as plt
import sys

if len(sys.argv) != 5:
    print 'Usage: ./csv_to_histogram.py [INPUT CSV] [OUTPUT PNG] [TARGET COL] [NUM BINS]'
    sys.exit(1)

in_fname = sys.argv[1]
out_fname = sys.argv[2]
col = int(sys.argv[3])
num_bins = int(sys.argv[4])

vals = []
with open(in_fname) as f:
    for line in f.read().splitlines():
        vals.append(float(line.split(', ')[col]))

plt.hist(vals, bins=num_bins)
plt.savefig(out_fname)