Pine script 如何使用pine识别信号趋势

我正在使用此代码查找上次蜡烛关闭时的SMI

a = input(10, "Percent K Length")
b = input(3, "Percent D Length")
ob = input(40, "Overbought")
os = input(-40, "Oversold")
// Range Calculation
ll = lowest (low, a)
hh = highest (high, a)
diff = hh - ll
rdiff = close - (hh+ll)/2

avgrel = ema(ema(rdiff,b),b)
avgdiff = ema(ema(diff,b),b)

// SMI calculations
SMI = avgdiff != 0 ? (avgrel/(avgdiff/2)*100) : 0

SMIsignal = ema(SMI,b)
emasignal = ema(SMI, 10)

代码在关闭时为我提供了当前的SMI信号和EMA信号，并且工作正常

仅当电流信号在最后3（例如）烛光中降低时，才可能有电流信号吗 如果SMI信号在最后3个（例如）烛光中未降低，则为空（零）SMI信号值？

SMItmp=float（na）
SMItmp:=ema（SMI，b）
sig=SMItmp[3]
SMItmp = float(na)
SMItmp := ema(SMI,b)
sig = SMItmp[3]<SMItmp[2] and SMItmp[2]<SMItmp[1] and SMItmp[1]<SMItmp[0]
SMIsignal = sig ? SMItmp : na