title: Using gsub or grep on factors in columns of data frame
body: <p>I have a data frame column that looks something like this: </p>
  
  <pre><code>&gt;df[,2]
  
  A    
  10
  10.1
  10a
  10a.1
  12a.6
  13b
  17
  3c.3
  </code></pre>
  
  <p>Except the column is about 70,000 rows. I want to find and remove all decimals that occur only at the ends of the factors in the column. </p>
  
  <p>Basically, how do I implement the 'grep()' or 'gsub()' functions correctly? </p>