BollingerPecentB Chart MT4

declare lower;

input AverageType = {default SMA, EMA};
input price = close;
input displace = 0;
input length = 20;
input Num_Dev_Dn = -2.0;
input Num_Dev_up = 2.0;

def upperBand;
def lowerBand;

switch (AverageType) {
case SMA:
upperBand = BollingerBandsSMA(price, displace, length, Num_Dev_Dn, Num_Dev_up).UpperBand;
lowerBand = BollingerBandsSMA(price, displace, length, Num_Dev_Dn, Num_Dev_up).LowerBand;
case EMA:
upperBand = BollingerBandsEMA(price, displace, length, Num_Dev_Dn, Num_Dev_up).UpperBand;
lowerBand = BollingerBandsEMA(price, displace, length, Num_Dev_Dn, Num_Dev_up).LowerBand;
}

plot PercentB = (price - lowerBand) / (upperBand - lowerBand) * 100;
plot ZeroLine = 0;
plot HalfLine = 50;
plot UnitLine = 100;

PercentB.SetDefaultColor(GetColor(1));
PercentB.SetLineWeight(1);
ZeroLine.SetDefaultColor(GetColor();
HalfLine.SetDefaultColor(GetColor();
UnitLine.SetDefaultColor(GetColor();