title: Multiple boxplots in one in R
body: <p>Hi I need to plot a boxplot in R.
      I have two matrices a and b.
      I created a boxplot for <code>a</code> and want to create boxplot for <code>b</code> on the same plot for <code>a</code>.
      The boxplots of the <code>b</code> matrix should lie on the whiskers of the boxplot for <code>a</code>.</p>
  
  <p>Is there a way I can do it in R ??</p>