title: What does n=n( ) mean in R?
body: <p>The other day I was reading the following lines in R and I don't understand what the <code>%&gt;%</code> and <code>summarise(n=n())</code> and <code>summarise(total=n())</code> meant. I understand the <code>group_by</code> and <code>ungroup</code> methods though.</p>
  
  <p>Can someone help out? There isn't any documentation for this either.</p>
  
  <pre><code>library(dplyr)
  net.multiplicity &lt;- group_by(net, nodeid, epoch) %&gt;% summarise(n=n()) %&gt;%
                      ungroup() %&gt;% group_by(n) %&gt;% summarise(total=n())
  </code></pre>