public static function get_inference_result(Language_variable_collection $langvar_coll, $method = 'closure_addition')
 {
     if (is_null(Fuzzy_inference_engine::$engine)) {
         $class_name = 'Fuzzy_inference_engine_' . $method;
         require_once $class_name . '.php';
         Fuzzy_inference_engine::$engine = new $class_name();
     }
     return Fuzzy_inference_engine::$engine->get_inference_result($langvar_coll);
 }
 private function calculate_inference_result()
 {
     $method = $this->CI->config->item('fuzzy_inference_engine');
     $this->_CI_load('library', 'fuzzy/Fuzzy_inference_engine', 'fuzzy_inference_engine');
     $this->inference_result = Fuzzy_inference_engine::get_inference_result($this, $method);
     $this->integrated_score = $this->inference_result->get_defuzzy_code();
 }