title: Extend matplotlib line plot across chart
body: <p>I've created this plot, but it doesn't extend all the way across the figure for some reason. Can anyone help explain why?</p>
  
  <p>Chart = <a href="https://i.stack.imgur.com/Ealg9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ealg9.png" alt="enter image description here"></a></p>
  
  <p>Code = </p>
  
  <pre><code>fig, ax = plt.subplots()
  ax.plot(trip.index, trip.gas, marker='.',linestyle='-')
  
  plt.xticks(np.arange(min(trip.index), max(trip.index), 7))
  ax.set_xticklabels(map(str, ax.get_xticks()/7))
  plt.xlabel('Week #')
  plt.ylabel('Trip Cost ($)')
  </code></pre>