title: Plotting categorical data with pandas and matplotlib
body: <p>I have a data frame with categorical data:</p>
  
  <pre><code>     colour  direction
  1    red     up
  2    blue    up
  3    green   down
  4    red     left
  5    red     right
  6    yellow  down
  7    blue    down
  </code></pre>
  
  <p>I want to generate some graphs, like pie charts and histograms based on the categories. Is it possible without creating dummy numeric variables? Something like</p>
  
  <pre><code>df.plot(kind='hist')
  </code></pre>