code: public function setPositionXL($positionXL)
      {
          if (!isset(self::$positionXLref[$positionXL])) {
              return false;
          }
  
          $this->position = self::$positionXLref[$positionXL];
  
          return true;
      }
docs: Set legend position using an Excel internal numeric value.
  
  @param int $positionXL see self::XL_LEGEND_POSITION_*
  
  @return bool