title: Position of maximum value in column in pandas
body: <p>I am newbie to this python.Consider i have 2 columns in a dataframe as follows:</p>
  
  <pre><code>A    B
  2    6
  3    7
  4    8
  </code></pre>
  
  <p>Now the maximum in column B is 8 and i need the value in column A for that, here its 4. Please help to solve this. Thanks in advance.</p>