title: Changing '0's in a list to avoid divide by 0 errors
body: <p>Suppose I have a nested list: <code>{{2,0,3},{4,0,4},{0,0,9}}</code>. I would like to change all the <code>0</code> to <code>0.00001</code>, or some other small value, so that the final result is <code>{{2,0.00001,3},{4,0.00001,4},{0.00001,0.00001,9}}</code></p>
  
  <p>How would I go about doing so without using the <code>For</code> and <code>If</code> functions?</p>
  
  <p>Thanks in advance.</p>