title: Is it possible to break axis labels into 2 lines in base graphics?
body: <p>I am trying to have the x-axis labels to be split into two lines. I would also like the labels to be rotated 45 degrees. How can I do this?</p>
  
  <p>What I have so far:</p>
  
  <pre><code>N &lt;- 10
  dnow &lt;- data.frame(x=1:N, y=runif(N), labels=paste("This is observation ",1:N))
  with(dnow, plot(x,y, xaxt="n", xlab=""))
  atn &lt;- seq(1,N,3)
  axis(1, at=atn, labels=labels[atn])
  </code></pre>