def alpha_004(code, end_date=None, fq="pre"):
    """
    公式:
        ((((SUM(CLOSE,8)/8)+STD(CLOSE,8))<(SUM(CLOSE,2)/2))?(-1*1):(((SUM(CLOSE,2)/2)<((SUM(CLOSE,8)/8)-STD(CLOSE,8)))?1:(((1<(VOLUME/MEAN(VOLUME,20)))||((VOLUME/MEAN(VOLUME,20))==1))?1:(-1*1))))
    Inputs:

        code: 股票池
        end_date: 查询日期
    Outputs:
        因子的值
    """
    end_date = to_date_str(end_date)
    func_name = sys._getframe().f_code.co_name
    return JQDataClient.instance().get_alpha_191(**locals())
公式:
((((SUM(CLOSE,8)/8)+STD(CLOSE,8))<(SUM(CLOSE,2)/2))?(-1*1):(((SUM(CLOSE,2)/2)<((SUM(CLOSE,8)/8)-STD(CLOSE,8)))?1:(((1<(VOLUME/MEAN(VOLUME,20)))||((VOLUME/MEAN(VOLUME,20))==1))?1:(-1*1))))
Inputs:

code: 股票池
end_date: 查询日期
Outputs:
因子的值
jqdatasdk/alpha191.py