Smoothed RSI

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//  Copyright by HPotter v1.0 03/09/2014
// This is new version of RSI oscillator indicator, developed by John Ehlers. 
// The main advantage of his way of enhancing the RSI indicator is smoothing 
// with minimum of lag penalty. 
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study(title="Smoothed RSI")
Length = input(10, minval=1)
xValue = (close + 2 * close[1] + 2 * close[2] + close[3] ) / 6
CU23 = sum(iff(xValue > xValue[1], xValue - xValue[1], 0), Length)
CD23 = sum(iff(xValue < xValue[1], xValue[1] - xValue, 0), Length)
nRes = iff(CU23 + CD23 != 0, CU23/(CU23 + CD23), 0)
plot(nRes, color=blue, title="Smoothed RSI")