DiNapoli Detrended Oscillator

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//  Copyright by HPotter v1.0 02/04/2015
// DiNapoli Detrended Oscillator
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study(title="DiNapoli Detrended Oscillator")
Length = input(14, minval=1)
hline(0, color=gray, linestyle=line)
xSMA = sma(close, Length)
nRes = close - xSMA
plot(nRes, color=blue, title="DiNapoli")