title: Python Pandas datetime64[ns] comparision
body: <p>I'm trying to use indexing to select rows in my dataframe after the date 2011-01-01. I used following line of code to return only part of dataframe that is after 2011-01-01 </p>
  
  <pre><code>  df = df[df.Date &gt; np.datetime64('2011-01-01 00:00:00')]
  </code></pre>
  
  <p>I don't get an error. However, I only see dates that are of 2016 year nothing on 2011. When I manually open file I can see that there are plenty of entries starting with 2011 year.</p>
  
  <p>What do I do wrong here? Any ideas?</p>
  
  <p>Thanks!</p>
  
  <p>Here is a sniped of data:<a href="http://i.stack.imgur.com/YhEa3.jpg" rel="nofollow">enter image description here</a></p>