title: How to filter a numpy.ndarray by date?
body: <p>I have a 2d numpy.array, where the first column contains datetime.datetime objects, and the second column integers:</p>
  
  <pre><code>A = array([[2002-03-14 19:57:38, 197],
         [2002-03-17 16:31:33, 237],
         [2002-03-17 16:47:18, 238],
         [2002-03-17 18:29:31, 239],
         [2002-03-17 20:10:11, 240],
         [2002-03-18 16:18:08, 252],
         [2002-03-23 23:44:38, 327],
         [2002-03-24 09:52:26, 334],
         [2002-03-25 16:04:21, 352],
         [2002-03-25 18:53:48, 353]], dtype=object)
  </code></pre>
  
  <p>What I would like to do is select all rows for a specific date, something like</p>
  
  <pre><code>A[first_column.date()==datetime.date(2002,3,17)]
  array([[2002-03-17 16:31:33, 237],
             [2002-03-17 16:47:18, 238],
             [2002-03-17 18:29:31, 239],
             [2002-03-17 20:10:11, 240]], dtype=object)
  </code></pre>
  
  <p>How can I achieve this?</p>
  
  <p>Thanks for your insight :)</p>