title: Issue in R 'x' must be atomic"
body: <p>Here is my code from the package phytools in R, I am trying to run a summary of my simtrees which must be in the class phylo or multiphylo but when I run the code below I get this error. </p>
  
  <pre><code>class(YY)&lt;-"multiPhylo"
  class(YY)
  [1] "multiPhylo"
  describe.simmap(YY)
  
  YY &lt;- describe.simmap(simtrees, plot=F)
   Error in sort.int(x, na.last = na.last, decreasing = decreasing, ...) : 
      'x' must be atomic
  </code></pre>