title: How to create graphs of relative frequency from pandas dataframe
body: <p>I know that it's possible to create a histogram from a pandas dataframe column with matplotlib.pyplot using the code:</p>
  
  <pre><code>df.plot.hist(y='Distance')
  </code></pre>
  
  <p>Which creates a graph like this:</p>
  
  <p><a href="https://i.stack.imgur.com/rP4E2.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/rP4E2.png" alt="Graph one"></a></p>
  
  <p>However what I'm looking for is a plot of relative frequency, expressed as a percentage of the total. I'd also like for the graph to have an overflow bin at 300 so that it looks something along the lines of:
  <a href="https://i.stack.imgur.com/4YaXW.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/4YaXW.png" alt="Graph two"></a></p>