title: Creating new binary columns from single string column in pandas
body: <p>I've seen this before and simply can't remember the function.</p>
  
  <p>Say I have a column "Speed" and each row has 1 of these values:</p>
  
  <pre><code>'Slow', 'Normal', 'Fast'
  </code></pre>
  
  <p>How do I create a new dataframe with all my rows except the column "Speed" which is now 3 columns: "Slow" "Normal" and "Fast" which has all of my rows labeled with a 1 in whichever column the old "Speed" column was. So if I had:</p>
  
  <pre><code>print df['Speed'].ix[0]
  &gt; 'Normal'
  </code></pre>
  
  <p>I would not expect this:</p>
  
  <pre><code>print df['Normal'].ix[0]
  &gt;1
  
  print df['Slow'].ix[0]
  &gt;0
  </code></pre>