Formula:
HO[i] = MA[i]-CMA[i-Length/2-1], where
CMA = MVA(Median price) with [Length] number of periods,
MA = MVA(FlowValue) with [Smooth] number of periods,
FlowValue[i] = High[i], if Close[i]>Close[i-1],
FlowValue[i] = Low[i], if Close[i]<Close[i-1],
FlowValue[i] = (High[i]+Low[i])/2, if Close[i]=Close[i-1].
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