KDJ的老师们帮忙优化下，或者学哪个视频？

说无法识别我Series<Numeric> "K";这行Params Numeric Length(9); Numeric SlowLength(3); Numeric SmoothLength(3);Vars Series<Numeric> "K"; Series<Numeric> "D"; Series<Numeric> "J"; Defs Numeric SMAValue(Numeric Price,Numeric Length,Numeric Weight) { if(InvalidNumeric == Price || InvalidNumeric == Length || InvalidNumeric == Weight) { return InvalidNumeric; } return SMA(Price,Length,Weight); }Events OnReady() { SetBackBarMaxCount(1+Max(Max(Length,SlowLength),SmoothLength)); } OnBar(ArrayRef<Integer> indexs) { Range[0:DataSourceSize() - 1] { Numeric HighestValue = HighestFC(High, Length); Numeric LowestValue = LowestFC(Low, Length); Numeric k = (Close - LowestValue)/(HighestValue-LowestValue)*100; Numeric kValue = SMAValue(k,SlowLength,1); Numeric DValue = SMAValue(KValue,SmoothLength,1); if(kValue <> InvalidNumeric) { PlotNumeric("K",KValue); } if(DValue <> InvalidNumeric) { PlotNumeric("D",DValue); } if(kValue <> InvalidNumeric && DValue <> InvalidNumeric) { PlotNumeric("J",3*KValue - 2*DValue); } if ("J" > "k" > "D") { BuyToCover(0, Open); Buy(0, Open); } if ("J" < "k" < "D") { Sell(0, Open); SellShort(0, Open); } } }