title: Convert Column to Date Format (Pandas Dataframe)
body: <p>I have a pandas dataframe as follows:</p>
  
  <pre><code>Symbol  Date
  A       02/20/2015
  A       01/15/2016
  A       08/21/2015
  </code></pre>
  
  <p>I want to sort it by <code>Date</code>, but the column is just an <code>object</code>.</p>
  
  <p>I tried to make the column a date object, but I ran into an issue where that format is not the format needed. The format needed is <code>2015-02-20,</code> etc.</p>
  
  <p>So now I'm trying to figure out how to have numpy convert the 'American' dates into the ISO standard, so that I can make them date objects, so that I can sort by them.</p>
  
  <p>How would I convert these american dates into ISO standard, or is there a more straight forward method I'm missing within pandas?</p>