title: How to apply dunn.test for dataframes in R?
body: <p>I have a CSV file with two columns: group and weight.
  I'm able to do a Kruskal–Wallis test:</p>
  <pre><code>kruskal.test(Weight~Group, data=Data.df)
  </code></pre>
  <p>I want to calculate pairwise multiple comparisons with the control group (there are different treatments). I have tried <code>dunn.test.control</code>, but I only get errors. I don't think I'm using the command correctly.</p>
  <p>Any idea what I'm doing wrong? Feel free to show an example!</p>