title: Correlation in text using R
body: <p>My data looks like (example)</p>
  
  <pre><code>ID     Col1     Col2
  1232   ABCSD    abd
  2342   ABCSD    esw
  7643   ABCSD    rty
  9821   ETHS     fvc
  </code></pre>
  
  <p>I have <code>2845428</code> such rows. I want to find out how correlated each pair in <code>Col1</code> and <code>Col2</code> is. For example</p>
  
  <pre><code>ABCSD     abd     0.64
  ETHS      fvc     0.23
  </code></pre>
  
  <p>How can I go about it using R? Thanks</p>