title: Stacked chart in ggvis, rcharts for continuous data
body: <p>Below is a subset of the data I have. </p>
  
  <pre><code>Abby    John       Mike             Date
  4.0       6         3               03-30
  3.2       5         1               03-31
  4.0       6         3               04-01
  4.1       8         2               04-02
  6.0       6         1               04-03
  </code></pre>
  
  <p>Am trying to plot a stacked/grouped bar chart with date on the x axis and all the users data on the Y (for a particular date 3 grouped bars on the Y axis indicating Abby, John and Mike's data). I tried using the 
  Rcharts library example at: <a href="http://ramnathv.github.io/posts/rcharts-nvd3/index.html" rel="nofollow">http://ramnathv.github.io/posts/rcharts-nvd3/index.html</a> </p>
  
  <p>But unlike the one used there, my data is continuous and not a factor. Is there anyway I can do this using ggvis or rCharts? I have only used these 2 plotting libraries as yet.</p>
  
  <p>Appreciate any help or guidance. Thanks.</p>