batarang.js

angular.element($0).scope().someFunction();

console.js

// #someID could be any other element within same controller, i.e. same scope
angular.element(document.querySelector('#someID')).scope().someFunction();

html.html

<div id="someID" ng-controller="MainCtrl">
    // some stuff here
</div>

js.js

function MainCtrl($scope) {
    $scope.someFunction = function() {
        console.log("someFunction..");
    }
}