title: Generating grouped bar chart in R program with uneven number of bars per group
body: <p>I want to plot a grouped bar chart. The dataset which I'm using for a plot is very large. Here is a small subset of it:</p>
  
  <pre><code>Label size
  x     2 3 4 5 
  y     2 6 8
  z     1 6 8 
  a     2 2 
  b     4 7 9 10 11
  c     8 12
  </code></pre>
  
  <p>I want to plot a bar-chart in which, on x axis there would be labels, and on y axis there would be multiple bars of sizes given.</p>
  
  <p>For example here, <code>x</code> has sizes <code>2 3 4 5</code>. So there would be four bars with heights 2, 3 , 4 and 5. Then <code>y</code> has sizes <code>2 6 8</code>. So there would be 3 bars with sizes 2, 6 and 8 and so on.</p>
  
  <p>Can any one help me out?</p>