title: Error in match.names(clabs, names(xi)) : names do not match previous names
body: <ol>
  <li>I am creating a vector having <strong>5 age values</strong> and named it as <strong>boys_age</strong>. Likewise created a vector named <code>girls_age</code>. </li>
  </ol>
  
  <p>eg :</p>
  
  <pre><code>boys_age &lt;- c(18,15,16,17,19)
  girls_age&lt;- c(16,14,18,17,15)
  </code></pre>
  
  <ol start="2">
  <li><p>Then Append <code>rbind()</code> the two vectors to create <strong>data.frame</strong> such that I have two columns named <code>group</code> and <code>age</code>. </p></li>
  <li><p>The values from  <strong>boys_age</strong> and <strong>girls_age</strong> should be in the column <code>age</code>. The <code>group</code> column should have the category values, <strong>boys/girls</strong>, to identify the source vector.</p></li>
  </ol>