title: Plot a step function (cadlag) in R (two dots: continuity and discontinuity point)
body: <p>Essentially I want to plot a compound Poisson process. Everything works fine except that I don't know how to edit the plot parameters correctly.
  I want to have the continuity points with a full dot and the discontinuity points with an empty dot. Right now I only am able to manage the full dot. </p>
  
  <p>Minimal working example (plots an compound Poisson path with 10 jumps)</p>
  
  <pre><code>n &lt;- 10
  n.t &lt;- cumsum(rexp(n))
  x &lt;- c(0,cumsum(rnorm(n)))
  plot(stepfun(n.t, x), xlab="t", ylab="X",do.points = TRUE,pch = 16,col.points = "blue",verticals = FALSE)
  </code></pre>
  
  <p>So how can I add the discontinuity points to the right? Any idea? </p>