日下跌多少,DownDayBool,向下移动指标,Envelope,指数移动平均线(别名:EMA,MovingAverageExponential),指数移动平均振荡指标(别名:ExponentialMovingAverageOsc, EMAOscillator, EMAOsc, MovingAverageExponentialOscillator, MovingAverageExponentialOsc)