title: Quantiles of a data.frame
body: <p>There is a data.frame() for which's columns I'd like to calculate quantiles:</p>
  
  <pre><code>tert &lt;- c(0:3)/3
  data &lt;- dbGetQuery(dbCon, "SELECT * FROM tablename")
  quans &lt;- mapply(quantile, data, probs=tert, name=FALSE)
  </code></pre>
  
  <p>But the result only contains the last element of quantiles return list and not the whole result. I also get a warning <code>longer argument not a multiple of length of shorter</code>. How can I modify my code to make it work?</p>
  
  <p>PS: The function alone works like a charme, so I <em>could</em> use a for loop:</p>
  
  <pre><code>quans &lt;- quantile(a$fileName, probs=tert, name=FALSE)
  </code></pre>
  
  <p>PPS: What also works is <em>not</em> specifying <code>probs</code></p>
  
  <pre><code>quans &lt;- mapply(quantile, data, name=FALSE)
  </code></pre>