title: Google dashboard with filters from grouped data - how to chart grouped data
body: <p>I am looking to create a Google charts API dashboard with filtering but I would like to chart the data based on grouped data.  For example, I can create a datatable such as this:</p>
  
  <pre><code>salesman  cust_age  cust_sex  quantity
  Joe       21        Male      3
  Joe       30        Female    10
  Suzie     40        Female    2
  Dave      15        Female    5
  Dave      30        Male      10
  </code></pre>
  
  <p>I can appropriately create a dashboard that creates two controls (for cust_age and cust_sex) and any number of output graphs and tables all pulling from an external data source - this is pretty stock stuff, see <a href="http://code.google.com/apis/chart/interactive/docs/gallery/controls.html">http://code.google.com/apis/chart/interactive/docs/gallery/controls.html</a></p>
  
  <p>The problem that I am having is how to show all charts by grouped values.  Using a pie chart as an example, without any filters there are 5 slices of the pie (Joe, Joe, Suzie, Dave, Dave) - I would like to see only three (Joe, Suzie Dave).  Of course, when a control is applied everything should update.</p>
  
  <p>In other words, the filters should act on the original datatable, but the charts should be based on a grouped datatable.</p>
  
  <p>I would guess that we could use the grouping function:
  <a href="http://code.google.com/apis/ajax/playground/?type=visualization#group">http://code.google.com/apis/ajax/playground/?type=visualization#group</a>
  however I cannot seem to bind the filters to the larger datatable, update the grouped table, and then draw the charts based on the grouped table.</p>
  
  <p>Any thoughts?</p>