ボリンジャーバンドに基づくトレンド反転戦略

/*backtest
start: 2023-10-24 00:00:00
end: 2023-10-31 00:00:00
period: 10m
basePeriod: 1m
exchanges: [{"eid":"Futures_Binance","currency":"BTC_USDT"}]
*/

//@version=4

// Welcome to yet another script. This script was a lot easier since I was stuck for so long on the Donchian Channels one and learned so much from that one that I could use in this one
// This code should be a lot cleaner compared to the Donchian Channels, but we'll leave that up to the pro's
// This strategy has two entry signals, long = when price hits lower band, while above EMA, previous candle was bearish and current candle is bullish
// Short = when price hits upper band, while below EMA, previous candle was bullish and current candle is bearish
// Take profits are the opposite side's band(lower band for long signals, upper band for short signals). This means our take profit price will change per bar
// Our stop loss doesn't change, it's the difference between entry price and the take profit target divided by the input risk reward
// At the time of writing this, I could probably calculate that much easier by simply multiplying the opposite band by the input risk reward ratio
// Since I want to get this script out and working on the next one, I won't clean that up, I'm sorry
// strategy(shorttitle="BB Trending Reverse Strategy", title="Bollinger Bands Trending Reverse Strategy", overlay=true, default_qty_type = strategy.cash, default_qty_value = 150, initial_capital = 1000, currency = currency.USD, commission_type = "percent", commission_value = 0.036)

// The built-in Bollinger Band indicator inputs and variables, added some inputs of my own and organised the code
length              = input(20, minval=1)
src                 = input(close, title="Source")
mult                = input(2.0, minval=0.001, maxval=50, title="StdDev")
emaInput            = input(title = "EMA Input", type = input.integer, defval = 200, minval = 10, maxval = 400, step = 1)
riskreward          = input(title = "Risk/Reward Ratio", type = input.float, defval = 1.50, minval = 0.01, maxval = 100, step = 0.01)
offset              = input(0, "Offset", type = input.integer, minval = -500, maxval = 500)
basis               = sma(src, length)
dev                 = mult * stdev(src, length)
upper               = basis + dev
lower               = basis - dev
ema                 = ema(close, emaInput)

// These are our conditions as explained above
entryLong           = low[1] <= lower[1] and low <= lower and low > ema
entryShort          = high[1] >= upper[1] and high >= upper and high < ema
reversecandleLong   = close > open and close[1] < open[1]
reversecandleShort  = close < open and close[1] > open[1]
var stopLong        = 0.0
var stopShort       = 0.0

// These are our entry signals, notice how the stop condition is within the if statement while the strategy.exit is outside of the if statement, this way the take profit targets trails up or down depending on what the price does
if reversecandleLong and entryLong and strategy.position_size == 0
    stopLong := (((close / upper - 1) * riskreward + 1) * close)
    strategy.entry("Long Entry", strategy.long, comment = "Long Entry")
    
strategy.exit("Exit Long", "Long Entry", limit = upper, stop = stopLong, comment = "Exit Long")

if reversecandleShort and entryShort and strategy.position_size == 0
    stopShort := (((close / lower - 1) / riskreward + 1) * close)
    strategy.entry("Short Entry", strategy.short, comment = "Short Entry")

strategy.exit("Exit Short", "Short Entry", limit = lower, stop = stopShort, comment = "Exit Short")


// The built-in Bollinger Band plots
plot(basis, "Basis", color=#872323, offset = offset)
p1 = plot(upper, "Upper", color=color.teal, offset = offset)
p2 = plot(lower, "Lower", color=color.teal, offset = offset)
fill(p1, p2, title = "Background", color=#198787, transp=95)
plot(ema, color=color.red)

// These plots are to check the stoplosses, they can  make a mess of your chart so only use these if you want to make sure these work
// plot(stopLong)
// plot(stopShort)