High - EMA

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//  Copyright by HPotter v1.0 02/07/2014
// This indicator plots the difference between the High (of the previous period)
// and an exponential moving average (13 period) of the Close (of the previous period).
// You can use in the xPrice any series: Open, High, Low, Close, HL2, HLC3, OHLC4 and ect...
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study(title="High - EMA", shorttitle="High - EMA")
Length = input(13, minval=1)
xPrice = close  // You can use any series
xEMA = ema(xPrice, Length)
nRes = high[1] - nz(xEMA[1])
plot(nRes, color=blue, title="High - EMA")