title: Box plot showing mean as a line
body: <p>Is it possible to create a boxplot that shows both mean and median as a line with the standard boxplot function of R ? My current solution displays the mean as a cross:</p>
  
  <pre><code>set.seed(1234)
  values &lt;- runif(10,0,1)
  boxplot(values)
  points(mean(values),col="red",pch=4,lwd = 4)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/yAodo.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yAodo.png" alt="Image of boxplot"></a></p>