from matplotlib.finance import quotes_historical_yahoo
from matplotlib.dates import DateFormatter 
from matplotlib.dates import DayLocator 
from matplotlib.dates import MonthLocator
import sys
from datetime import date
import matplotlib.pyplot as plt
import numpy as np

today = date.today()
start = (today.year - 1, today.month, today.day)

symbol = 'DISH'

if len(sys.argv) == 2:
   symbol = sys.argv[1]

quotes = quotes_historical_yahoo(symbol, start, today)
quotes = np.array(quotes)
dates = quotes.T[0]
close = quotes.T[4]


alldays = DayLocator()              
months = MonthLocator()
month_formatter = DateFormatter("%b %Y")

fig = plt.figure()
ax = fig.add_subplot(111)
ax.plot(dates, close) 
plt.fill_between(dates, close.min(), close, where=close>close.mean(), facecolor="green", alpha=0.4)
plt.fill_between(dates, close.min(), close, where=close<close.mean(), facecolor="red", alpha=0.4)
ax.xaxis.set_major_locator(months)
ax.xaxis.set_minor_locator(alldays)
ax.xaxis.set_major_formatter(month_formatter)
ax.grid(True)
fig.autofmt_xdate()
plt.show()