title: How can I use merge to cbind two dataframes
body: <p>Suppose I have two dataframes:</p>
  
  <pre><code>df1 &lt;- data.frame(matrix(rnorm(10*10),ncol=10))
  df2 &lt;- data.frame(matrix(rnorm(10*10),ncol=10))
  colnames(df1) &lt;- 1:10
  colnames(df2) &lt;- 11:20
  </code></pre>
  
  <p>How do I use <code>merge</code> to <code>cbind</code> these (I already know about <code>cbind</code> but I am interested in the application of <code>merge</code> here).</p>