KDJ Indicator

//@version=6
indicator("KDJ指标", overlay=false)  // 定义指标名称为“KDJ Indicator”，不覆盖在价格图表上

// Input parameters
length = input.int(9, title="KDJ Length")  // 输入参数：KDJ的周期长度
smoothK = input.int(3, title="K Smoothing")  // 输入参数：K值的平滑周期
smoothD = input.int(3, title="D Smoothing")  // 输入参数：D值的平滑周期

// Calculate RSV
highestHigh = ta.highest(high, length)  // 计算指定周期内的最高价
lowestLow = ta.lowest(low, length)  // 计算指定周期内的最低价
rsv = (close - lowestLow) / (highestHigh - lowestLow) * 100  // 计算RSV（未成熟随机值）

// Calculate K, D, and J
k = ta.ema(rsv, smoothK)  // 计算K值，使用RSV的指数移动平均
d = ta.ema(k, smoothD)  // 计算D值，使用K值的指数移动平均
j = 3 * d - 2 * k  // 计算J值，J值为k值的三倍减去d值的两倍

// Plot K, D, and J
plot(k, color=color.blue, title="K")  // 绘制K值，颜色为蓝色
plot(d, color=color.orange, title="D")  // 绘制D值，颜色为橙色
plot(j, color=color.white, title="J")  // 绘制J值，颜色为白色

// Add overbought and oversold levels
hline(80, "Overbought", color=color.red, linestyle=hline.style_dotted)  // 添加超买水平线，值为80，颜色为红色，虚线样式
hline(20, "Oversold", color=color.green, linestyle=hline.style_dotted)  // 添加超卖水平线，值为20，颜色为绿色，虚线样式

// Calculate cross signals
crossBuy = ta.crossover(k - d, 0)  // 判断K-D从小于0到大于0的交叉（买入信号）
crossSell = ta.crossunder(k - d, 0)  // 判断K-D从大于0到小于0的交叉（卖出信号）

// Plot buy and sell signals on the price chart
plotshape(crossBuy, style=shape.labelup, location=location.belowbar, color=color.red, text="多", title="提示做多信号")  // 绘制买入信号
plotshape(crossSell, style=shape.labeldown, location=location.abovebar, color=color.green, text="空", title="提示做空信号")  // 绘制卖出信号

// Detect bearish divergence (顶背离)
bearishDivergence = ta.highest(close, length) > ta.highest(close[1], length) and ta.highest(j, length) <= ta.highest(j[1], length)

// Plot bearish divergence signal
plotshape(bearishDivergence, style=shape.triangledown, location=location.abovebar, color=color.green, text="↓", title="顶背离信号")