public function index(Manager $fractal, RatioconstraintTransformer $ratioconstraintTransformer)
 {
     // show all
     $records = Ratioconstraint::all();
     $collection = new Collection($records, $ratioconstraintTransformer);
     $data = $fractal->createData($collection)->toArray();
     return $this->respond($data);
 }