title: Pandas max value index
body: <p>I have a Pandas DataFrame with a mix of screen names, tweets, fav's etc.  I want find the max value of 'favcount' (which i have already done) and also return the screen name of that 'tweet'</p>
  
  <pre><code>df = pd.DataFrame()
  df['timestamp'] = timestamp
  df['sn'] = sn
  df['text'] = text
  df['favcount'] = fav_count
  
  
  print df
  print '------'
  print df['favcount'].max()
  </code></pre>
  
  <p>I cant seem to find anything on this, can anyone help guide me in the right direction?</p>