title: How can I reformat the date on the x-axis of figure using matplotlib?
body: <p>When I run <code>df.index</code>, it outputs the format as YYYY-MM-DD, which is how I would like it viewed on the figure. Instead, at each major tick the values are, for example, 1.48 1e18, 1.50 1e18, etc. Is there a simple way to convert to the aforementioned format?  </p>
  
  <pre><code>from datetime import datetime as dt
  import matplotlib.pyplot as plt
  from matplotlib import style
  import pandas as pd
  import pandas_datareader.data as web
  
  start = dt(2016, 6, 1)
  end = dt.now()
  
  df = web.get_data_yahoo('AAPL', start, end, interval = 'd')
  
  fig = plt.figure()
  ax = fig.add_subplot(1,1,1)
  ax.plot(df.index, df['Adj Close'], label='ADJ CLOSE')
  ax.set_xlabel('Date')
  ax.set_ylabel('Price')
  ax.legend()
  plt.show()
  </code></pre>
  
  <p>Using Python 3.6.2 and pandas 0.21.0</p>