title: grouping data in R
body: <p>I have this data frame, this is a daily data. For every day, I have free space for each file system. I like to graph this. I was thinking to put each file system on its own column to create R graphs. How can I go about doing this. Without moving them to their own columns, can I create a chart for each file system for each day?</p>
  
  <pre><code>     Date     fileSystem FreeSpace
  2011-12-03     /var          99.785
  2011-12-03     /opt          30.494
  2011-12-03     /tmp          55.643
  2011-12-03     /data         37.846
  2011-12-03     /ora          0.578
  2011-12-04     /var          99.785
  2011-12-04     /opt          30.494
  2011-12-04     /tmp          55.643
  2011-12-04    /data         37.846
  2011-12-04     /ora          0.578
  </code></pre>