Angular: Empty Fiddle

http://angularjs.org/

HTML

<script src="http://code.angularjs.org/angular-1.0.1.js"></script>
<div ng-controller="MyCtrl">
  <div>
      <label>
      <input type="radio" ng-model="nsClass" value="F" ng-disabled='btn_radio_ns_class_disable'>
      F
      </label><br/>
      <label>
      <input type="radio" ng-model="nsClass" value="CN" ng-disabled='btn_radio_ns_class_disable'>
      CN</label><br/>
      <label>
      <input type="radio"ng-model="nsClass" value="O" ng-disabled='btn_radio_ns_class_disable'>
      O</label>
      <button ng-click="click()">
        Cick me
      </button>
  </div>
</div>

JavaScript

var myApp = angular.module('myApp',[]);

//myApp.directive('myDirective', function() {});
//myApp.factory('myService', function() {});

function MyCtrl($scope) {
    $scope.nsClass = '';
    
    $scope.click = function () {
    	 $scope.nsClass = 'F';
    }
}