"""
  COMP 364 Lecture 17: Bar charts
  Author: Mathieu Perreault
"""

import matplotlib.pyplot as plt
import sys

# Bar chart demo
frequencies = {}
for line in open(sys.argv[1]):
  line = line.strip('\n')
  for c in line:
    frequencies[c] = frequencies.get(c, 0) + 1
    
print frequencies
plt.figure()
howmany = len(frequencies)
plt.bar([0, 1, 2, 3], frequencies.values(), width=0.5)
#plt.bar(range(howmany), frequencies.values(), width=0.5)
plt.xticks([0,1,2,3], frequencies.keys())
#plt.xticks(range(howmany), frequencies.keys())
plt.ylabel('Number of occurrences')
plt.xlabel('Nucleotides')
plt.show()