/** * Sets the baseline for the axis. * * This option is only supported for a continuous axis. * * @param mixed Must match type defined for the column, [ number | jsDate ]. * @throws InvalidConfigValue * @return Axis */ public function baseline($baseline) { if (Utils::isJsDate($baseline)) { $this->baseline = $baseline->toString(); } else { if (is_int($baseline)) { $this->baseline = $baseline; } else { throw $this->invalidConfigValue(__FUNCTION__, 'int | jsDate', 'int if column is "number", jsDate if column is "date"'); } } return $this; }