javascript - Get random number in ng-repeat angular -

i need random number in cycle angular. tried in template:

   <div ng-app="app" ng-controller="base" >     <div ng-repeat="item in items">       <img ng-src="/img/img{{getrandomimg()}}.png">      </div>    </div> 

and function in base controller:

$scope.getrandomimg = function(){     return math.floor((math.random()*3)+1); } 

when page loaded have error: $rootscope:infdig infinite $digest loop

i tried directive

app.directive('randomimage', [     function() {         return {             restrict: 'a',             link: function($scope, element, attrs) {                 var rand = math.floor((math.random()*3)+1);                  $(element).attr('src', '/img/tracks/trackimg'+rand+'.png');             }         }      } ]); 

and in template:

 <div ng-app="app" ng-controller="base" ng-repeat="item in items">       <img data-random-image="">   </div> 

it works correctly. when update items in controller not re-generated images, remain same. why?

this angular documentation:

"this error occurs when application's model becomes unstable , each $digest cycle triggers state change , subsequent $digest cycle. angular detects situation , prevents infinite loop causing browser become unresponsive.

for example, situation can occur setting watch on path , subsequently updating same path when value changes."

<div ng-repeat="user in getusers()">{{ user.name }}</div>  ...  $scope.getusers = function() {   return [ { name: 'hank' }, { name: 'francisco' } ]; }; 

the problem in "items" array. read this: https://docs.angularjs.org/error/$rootscope/infdig