I currently have this for the modified Bollinger Bands as pointed out by McMillan from here but the bands do not look like what they should.
Here is some more information from tradingview.
Here is some more information from tradingview.
Ruby:
#
# Larry McMillan’s Modified Bollinger Bands
#
input price = close;
input length = 20;
input Num_Dev0 = 3;
input Num_Dev1 = 4.0;
input averageType = AverageType.Simple;
# def sDev = stdev(data = price, length = length);
def closeLog = Log(price / price[1]);
def sDev = stdev(closeLog, length)* Sqrt(length / (length – 1));
plot MidLine = MovingAverage(averageType, data = price, length = length);
plot UpperBand0 = MidLine * Exp(Num_Dev0 * sDev);
plot LowerBand0 = MidLine * Exp(-Num_Dev0 * sDev);
plot UpperBand1 = MidLine * Exp(Num_Dev1 * sDev);
plot LowerBand1 = MidLine * Exp(-Num_Dev1 * sDev);
UpperBand0.SetDefaultColor(GetColor(3));
LowerBand0.SetDefaultColor(GetColor(3));
MidLine.SetDefaultColor(GetColor(1));
UpperBand1.SetDefaultColor(GetColor(5));
LowerBand1.SetDefaultColor(GetColor(0));
Last edited: