title: pandas dataframe getting daily/weekly/hourly data
body: <p>I have a pandas dataframe with index = datetime.datetime(year,month,day,hour,minute)</p>
  
  <p>I want to be able to use this to get hourly/ daily /weekly data where hourly data would be the last entry corresponding to every hour in the frame.</p>
  
  <p>Is there any inbuilt way to do this? I tried making cases e.g. in case of daily data, i changed the hour and minute entry to zero, but I still have a dataframe with multiple entries for the same day. How can I get the last entry corresponding to each day?</p>
  
  <p>sample dataframe:</p>
  
  <pre><code>         index                x          y
  2016-01-01 00:07:00-05:00   1.000      0.000
  2016-01-01 00:10:00-05:00   1.000      0.000
  2016-01-01 00:15:00-05:00   1.000      0.000
  2016-01-01 00:16:00-05:00   1.000      0.000
  2016-01-01 00:20:00-05:00   1.000      0.000
  2016-01-01 00:21:00-05:00   1.000      0.000
  2016-01-01 00:26:00-05:00   1.000      0.000
  2016-01-01 00:31:00-05:00   1.000      0.000
  2016-01-01 00:37:00-05:00   1.000      0.000
  2016-01-01 00:40:00-05:00   1.000      0.000
  2016-01-01 00:46:00-05:00   1.000      0.000
  2016-01-01 00:51:00-05:00   1.000      0.000
  2016-01-01 00:56:00-05:00   1.000      0.000
  2016-01-03 19:26:00-05:00   1.000      0.000
  2016-01-03 19:34:00-05:00   1.000      0.000
  2016-01-03 20:02:00-05:00   1.000      0.000
  2016-01-03 20:06:00-05:00   1.000      0.000
  2016-01-03 20:07:00-05:00   1.000      0.000
  2016-01-03 20:08:00-05:00   1.000      0.000
  2016-01-03 20:10:00-05:00   1.000      0.000
  2016-01-03 20:11:00-05:00   1.000      0.000
  2016-01-03 20:12:00-05:00   1.000      0.000
  2016-01-03 20:13:00-05:00   1.000      0.000
  </code></pre>