title: How to initialize form field value?
body: <p>Is there a way to initialize the following form fields so the Angular code doesn't display "NaN" when the form is loaded?  Having the value start at zero would be nice.</p>
  
  <pre><code>&lt;input type="text" id="field1" value="0"/&gt;
  &lt;input type="text" id="field2" value="0"/&gt;
  &lt;br /&gt;
  
  Total {{field1*50--field2}}
  </code></pre>
  
  <p><a href="http://plnkr.co/edit/Cn0tCJlclIMXivli1is0?p=preview" rel="nofollow">http://plnkr.co/edit/Cn0tCJlclIMXivli1is0?p=preview</a></p>