BollingerBandTrendFollowStrategy.easylanguage

Inputs:
    Length(20),               // Length for Bollinger Bands
    MultiplierUpper(1),       // Multiplier for the upper band
    MultiplierLower(0.5),     // Multiplier for the lower band
    RiskPercentage(1.00),     // Risk percentage per trade
    ATRMultiplier(2),         // ATR multiplier
    ATRLength(20),            // ATR length
    EnableFilter(false),      // Enable filter
    BenchmarkSymbol("SPX");   // Benchmark symbol

Vars:
    CentralMA(0),             // Central moving average for Bollinger Bands
    UpperBand(0),             // Upper Bollinger Band
    LowerBand(0),             // Lower Bollinger Band
    BenchmarkClose(0),        // Closing price of the benchmark
    Filter(false),            // Filter condition
    Qty(0),                   // Trade quantity
    BuyCondition(false),      // Buy condition
    SellCondition(false);     // Sell condition

// **********************************
// Functions
// **********************************


// **********************************
// Perform calculations and analysis
// **********************************

// Bollinger Bands calculations
CentralMA = Average(Close, Length);
UpperBand = CentralMA + MultiplierUpper * StdDev(Close, Length);
LowerBand = CentralMA - MultiplierLower * StdDev(Close, Length);

// Filter
If EnableFilter then
    BenchmarkClose = Close of Data2;
    Filter = BenchmarkClose >= Average(Close of Data2, 200);
else
    Filter = true;

// Trade quantity
Qty = ((RiskPercentage / 100) * I_OpenEquity) / (ATRMultiplier * AvgTrueRange(ATRLength));

// Entry and exit conditions
BuyCondition = Close crosses over UpperBand and Filter;
SellCondition = Close crosses under LowerBand;

// **********************************
// Manage trade
// **********************************

If BuyCondition then
    Buy("Long") Qty shares next bar at market;
If SellCondition then
    Sell("Long") Qty shares next bar at market;