title: Combine two data.frames in R with differing rows
body: <p>I have two tables one with more rows than the other. I would like to filter the rows out that both tables share. I tried the solutions proposed <a href="https://stackoverflow.com/questions/3171426/compare-two-data-frames-to-find-the-rows-in-data-frame-1-that-are-not-present-in">here</a>.</p>
  
  <p>The problem, however, is that it is a large data-set and computation takes quite a while. Is there any simple solution? I know how to extract the shared rows of both tables using: </p>
  
  <pre><code>rownames(x1)-&gt;k
  rownames(x)-&gt;l
  which(rownames(x1)%in%l)-&gt;o
  </code></pre>
  
  <p>Here x1 and x are my data frames. But this only provides me with the shared rows. How can I get the unique rows of each table to then exclude them respectively? So that I can just cbind both tables together?</p>