title: If colnames = rownames then I want NA on r
body: <p>I'm looking for a function or code that allows me to change the values of my matrix depending if the rownames and colnames are the same, to replace 0 by NA, to get something like this:</p>
  <pre><code>     X    112101      115301      115701    135901    195902   
  112101 NA    
  115301 0.9315254 NA
  115701 0.9974359 0.007692308 NA
  135901 0.5991379 0.000000000 1.000000000 NA  
  195902 0.5348837 0.502527806 0.266666667 0.4816810 NA
  </code></pre>
  <p>I'm interested if you have any ideas. Thanks for help.</p>