title: no visible global function definition for ‘median’
body: <p>Since the latest R update I get the Note </p>
  
  <blockquote>
    <p>summary.xmlImport: no visible global function definition for ‘median’</p>
  </blockquote>
  
  <p>in the CRAN check. Further notes refer to <code>read.table</code>, <code>write.table</code> and other standard functions in R.</p>
  
  <p>When I have a look on my file summary.xmlImport, the file looks like this:</p>
  
  <pre><code>summary.xmlImport &lt;- function(object, ...){
  
     rowCount &lt;- sapply(object,nrow)
     cat("Summary of xmlImport object\n")
     cat("---------------------------\n")
     cat("Sequences    :",length(object),"\n")
     cat("Min hits     :",min(rowCount),"\n")
     cat("Average hits :",mean(rowCount),"\n")
     cat("Median hits  :",median(rowCount),"\n")
     cat("Max hits     :",max(rowCount),"\n")
     invisible(object)
  
  } 
  </code></pre>
  
  <p>I cannot understand, why I should add now the <code>median</code> function to the NAMESPACE, but why not the <code>min</code>, <code>mean</code>, etc. The note is only about the <code>median</code>function.</p>
  
  <p>Anybody an idea what the reason for the Note is and how to fix it? I noted that there are tons of R packages that have currently the same Note.</p>
  
  <p>I can understand this warning in the context of a non-declared variable, but I would assume that <code>median()</code>, <code>read.table()</code> and such functions are globally visible in R, especially as <code>mean()</code>seems to be!?</p>
  
  <p>EDIT: I only receive the Note on CRAN, but not on my local computer what makes the search for the solution a bit nasty... The session info of my computer:</p>
  
  <pre><code>&gt; sessionInfo()
  R version 3.2.1 (2015-06-18)
  Platform: x86_64-pc-linux-gnu (64-bit)
  Running under: Ubuntu 14.04.2 LTS
  </code></pre>