public function run($id = null)
 {
     if ($this->checkAccess) {
         call_user_func($this->checkAccess, $this->id);
     }
     $model = new $this->modelClass();
     $model->load(Yii::$app->getRequest()->getBodyParams(), '');
     $formula = new Formula();
     $formula->variable = Yii::$app->getRequest()->getBodyParam('variable');
     $formula->type = Formula::INPUT_TYPE;
     $formula->title = Yii::$app->getRequest()->getBodyParam('title');
     $formula->calculation_id = Yii::$app->getRequest()->getBodyParam('calculation_id');
     if ($formula->validate()) {
         $formula->save();
         $model->formula_id = $formula->id;
         $model->save();
     } else {
         return $formula;
     }
     return $model;
 }