title: NA in clustering functions (kmeans, pam, clara). How to associate clusters to original data?
body: <p>I need to cluster some data and I tried <code>kmeans</code>, <code>pam</code>, and <code>clara</code> with R. </p>
  
  <p>The problem is that my data are in a column of a data frame, and contains NAs.</p>
  
  <p>I used <code>na.omit()</code> to get my clusters. But then how can I associate them with the original data? The functions return a vector of integers without the NAs and they don't retain any information about the original position.</p>
  
  <p>Is there a clever way to associate the clusters to the original observations in the data frame? (or a way to intelligently perform clustering when NAs are present?)</p>
  
  <p>Thanks</p>