title: Netcdf averages time varable when averaging multiple .nc files
body: <p>I have averaged a bunch of hourly netCDF files (for one year) to create one large netCDF file that contains an average daily value. The time variable represents hours since 2005-1-1 00:00:00 and looks like this:</p>
  <pre><code>time = 11.5, 35.5, 59.5, 83.5, 107.5, 131.5, 155.5, 179.5, 203.5, 227.5...;
  </code></pre>
  <p>However, I would like the time variable to represent the beginning of the day so that it looks like this:</p>
  <pre><code>time = 0, 24, 48...;
  </code></pre>
  <p>Is there a way to manipulate the time variable so that it represents the beginning of the day instead of the middle of the day?</p>
  <p>Thanks!</p>