title: Why fillna does not work on float values?
body: <p>I try to replace in all the empty cell of a dataset the mean of that column.</p>
  
  <p>I use <code>modifiedData=data.fillna(data.mean())</code></p>
  
  <p>but it works only on integer column type.
  I have also a column with float values and in it <code>fillna</code> does not work.</p>
  
  <p>Why?</p>