title: Pyplot: using percentage on x axis
body: <p>I have a line chart based on a simple list of numbers. By default the x-axis is just the an increment of 1 for each value plotted. I would like to be a percentage instead but can't figure out how. So instead of having an x-axis from 0 to 5, it would go from 0% to 100% (but keeping reasonably spaced tick marks. Code below. Thanks!</p>
  
  <pre><code>from matplotlib import pyplot as plt
  from mpl_toolkits.axes_grid.axislines import Subplot
  
  data=[8,12,15,17,18,18.5]
  fig=plt.figure(1,(7,4))
  ax=Subplot(fig,111)
  fig.add_subplot(ax)
  plt.plot(data)
  </code></pre>