title: Table and group_by in dplyr
body: <pre><code>a&lt;-data_frame(id=c(rep("A",100),rep("B",78),rep("C",50)),
                vall=c(rep("x",100),rep("y",78),rep("x",50)),
                val=runif(228))
  </code></pre>
  
  <p>Now, I´d like to have the following output:</p>
  
  <pre><code>a2&lt;-a %&gt;% group_by(id) %&gt;% count(vall)
  table(a2$vall)
  </code></pre>
  
  <p>but, I´d prefer to have a oneliner and not having to create a2. Is there a smart way of doing this?</p>