title: Pandas and DateTime TypeError: cannot compare a TimedeltaIndex with type float
body: <p>I have a pandas DataFrame Series time differences that looks like::</p>
  
  <pre><code> print(delta_t)
  
   1       0 days 00:00:59
   3       0 days 00:04:22
   6       0 days 00:00:56
   8       0 days 00:01:21
   19      0 days 00:01:09
   22      0 days 00:00:36
   ...
  </code></pre>
  
  <p>(the full DataFrame had a bunch of NaNs which I dropped). </p>
  
  <p>I'd like to know which delta_t's are less than 1 day, 1 hour, 1 minute, 
  so I tried: </p>
  
  <pre><code>delta_t_lt1day = delta_t[np.where(delta_t &lt; 30.)]
  </code></pre>
  
  <p>but then got a: </p>
  
  <pre><code>TypeError: cannot compare a TimedeltaIndex with type float
  </code></pre>
  
  <p>Little help?!?!</p>