title: Include image in data frame R
body: <p>I have a data frame in R, something like this</p>
  
  <pre><code>       Score   Result
  1       1       Pass       
  2       0.8     Pass       
  3       1       Pass       
  4       0.5     Fail        
  5       0.3     Fail        
  6       0.2     Fail
  </code></pre>
  
  <p>Depending upon the value of Result (pass or fail), I would like to display thumbs-up or thumbs-down image when I write the data frame to the PDF.</p>
  
  <p>I don't want to use knitr or shiny. Any help would be appreciated.</p>