Ehler's Stochastic

#
# TD Ameritrade IP Company, Inc. (c) 2013-2024
#

declare lower;

input price = close;
input length = 20;
input cutoffLength = 10;
input over_bought = 0.8;
input over_sold = 0.2;
input mode = {default Predictive, Conventional};

def filt = reference EhlersRoofingFilter(price, cutoffLength);
def highestP = Highest(filt, length);
def lowestP = Lowest(filt, length);
def stoch = if (highestP - lowestP) != 0 then (filt - lowestP) / (highestP - lowestP) else 0;

plot Stochastic = reference EhlersSuperSmootherFilter(stoch, cutoffLength);
plot OverBought = over_bought;
plot OverSold = over_sold;
plot Buy;
plot Sell;
switch (mode) {
case Predictive:
    Buy = if Stochastic crosses below OverSold then OverSold + 0.05 else Double.NaN;
    Sell = if Stochastic crosses above OverBought then OverBought - 0.05 else Double.NaN;
case Conventional:
    Buy = if Stochastic crosses above OverSold then OverSold + 0.05 else Double.NaN;
    Sell = if Stochastic crosses below OverBought then OverBought - 0.05 else Double.NaN;
}

Stochastic.SetDefaultColor(GetColor(5));
OverBought.SetDefaultColor(GetColor(7));
OverSold.SetDefaultColor(GetColor(7));
Buy.SetDefaultColor(Color.UPTICK);
Buy.SetPaintingStrategy(PaintingStrategy.ARROW_UP);
Buy.HideBubble();
Sell.SetDefaultColor(Color.DOWNTICK);
Sell.SetPaintingStrategy(PaintingStrategy.ARROW_DOWN);
Sell.HideBubble();