How To Compute Parabolic SAR (Stop and Reverse) in Groovy?

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def computeSAR(def high, def low, def acceleration, def maxAcceleration) {
    def sar = []
    
    // initial values
    def sarPrev = low[1]
    def acc = acceleration
    def extremePoint = high[0]
    def trend = 1
    
    // loop through the data to calculate SAR
    for (int i = 2; i < high.size(); i++) {
        if (trend == 1) {
            if (low[i] < sarPrev) {
                sar.add(sarPrev)
                sarPrev = extremePoint
                acc = acceleration
                trend = -1
                extremePoint = low[i]
            } else {
                def sarCurrent = sarPrev + acc * (extremePoint - sarPrev)
                sar.add(sarCurrent)
                
                if (high[i] > extremePoint) {
                    extremePoint = high[i]
                    acc += acceleration
                }
            }
        } else {
            if (high[i] > sarPrev) {
                sar.add(sarPrev)
                sarPrev = extremePoint
                acc = acceleration
                trend = 1
                extremePoint = high[i]
            } else {
                def sarCurrent = sarPrev - acc * (sarPrev - extremePoint)
                sar.add(sarCurrent)
                
                if (low[i] < extremePoint) {
                    extremePoint = low[i]
                    acc += acceleration
                } 
            }
        }
    }
    
    return sar
}

// Example usage
def high = [10, 11, 12, 13, 14, 15, 16]
def low = [9, 10, 11, 12, 13, 14, 15]
def acceleration = 0.02
def maxAcceleration = 0.2

def sar = computeSAR(high, low, acceleration, maxAcceleration)
println sar