title: Subset rows according to a range of time
body: <p>I have a data frame that looks like that</p>
  
  <pre><code>            date_time loc_id node  energy   kgco2 
  1 2009-02-27 00:11:08     87  103 0.00000 0.00000 
  2 2009-02-27 01:05:05     87  103 7.00000 3.75900 
  3 2009-02-27 02:05:05     87  103 6.40039 3.43701 
  4 2009-02-27 03:05:05     87  103 4.79883 2.57697 
  5 2009-02-27 04:05:05     87  103 4.10156 2.20254 
  6 2009-02-27 05:05:05     87  103 2.59961 1.39599
  </code></pre>
  
  <p>Is there anyway I can subset it according to range of time, for example, 2am to 5am. I should then get a result that looks like this:</p>
  
  <pre><code>            date_time loc_id node  energy   kgco2  
  3 2009-02-27 02:05:05     87  103 6.40039 3.43701 
  4 2009-02-27 03:05:05     87  103 4.79883 2.57697 
  5 2009-02-27 04:05:05     87  103 4.10156 2.20254 
  </code></pre>