生成带角度和nvd3的条形图

Question

我正在尝试使用angularJS和nvD3生成条形图。我的控制器是这样的：

function initMyController(fac, $scope, DATA_URL, $http){
    $http.get(DATA_URL).success(function(response){
      console.log(response);
      var values = [];
      $scope.data = [];
      angular.forEach(response, function(item) {
        //in my response I have the correct values
        values.push({'label:' : item.label, 'value:' : item.value});
      });

      $scope.data = values;
    });
  }

在视图上我有这个

<div ng-controller="MyCtrl">
        <nvd3 options="options"
              data="data"
              config="config"
              events="events"
              api="api"></nvd3>

      </div>

但是在尝试渲染图形时我总是遇到这个错误。

TypeError: Cannot read property 'length' of undefined
    at http://localhost:9000/bower_components/nvd3/nv.d3.js:3684:78
    at Array.filter (native)
    at SVGSVGElement.<anonymous> (http://localhost:9000/bower_components/nvd3/nv.d3.js:3684:42)
    at http://localhost:9000/bower_components/d3/d3.js:8114:14
    at d3_selection_each (http://localhost:9000/bower_components/d3/d3.js:888:30)
    at Array.d3_transitionPrototype.each (http://localhost:9000/bower_components/d3/d3.js:8112:7)
    at Array.chart (http://localhost:9000/bower_components/nvd3/nv.d3.js:3664:15)
    at Array.d3_selectionPrototype.call (http://localhost:9000/bower_components/d3/d3.js:895:14)
    at Object.link.scope.api.updateWithData (http://localhost:9000/bower_components/angular-nvd3/dist/angular-nvd3.min.js:1:5556)
    at Object.link.scope.api.updateWithOptions (http://localhost:9000/bower_components/angular-nvd3/dist/angular-nvd3.min.js:1:4752)
  (anonymous function)  
  $get  
  $get.Scope.$digest    
  scopePrototype.$digest    
  $get.Scope.$apply 
  scopePrototype.$apply 
  done  
  completeRequest   
  requestLoaded 

我错过了什么？