title: Display values on heatmap in R
body: <p>I am working on a heatmap using heatmap.2 and would like to know if there is anyway to display the values on all heatmap positions. For example for the area representing "1" and rating I would like to display value "43", for "2" and privileges the value 51 and so on.</p>
  
  <p>My sample data is as follows: <img src="https://i.stack.imgur.com/2kBWV.png" alt="enter image description here"></p>
  
  <pre><code>            rating complaints privileges learning raises critical advance
        1      43         51         30       39     61       92      45
        2      63         64         51       54     63       73      47
        3      71         70         68       69     76       86      48
        4      61         63         45       47     54       84      35
  </code></pre>