用Java代码实现股票的kdj计算

KDJ 是股票领域中常用的技术指标之一，它由三条曲线组成，分别是 K 线、D 线和 J 线。KDJ 的计算非常复杂，需要用到一些中间变量和参数。下面是用 Java 代码实现 KDJ 计算的示例：

public class KDJ {
    public static void main(String[] args) {
        double[] prices = {10.0, 15.0, 12.0, 18.0, 20.0};
        double[] ks = new double[prices.length];
        double[] ds = new double[prices.length];
        double[] js = new double[prices.length];

        int period = 9;
        double k1 = 2.0 / 3.0;
        double k2 = 1.0 / 3.0;

        double[] lows = new double[period];
        double[] highs = new double[period];

        for (int i = 0; i < prices.length; i++) {
            double p = prices[i];
            double rsv = 0.0;

            if (i >= period) {
                double low = Double.MAX_VALUE;
                double high = Double.MIN_VALUE;

                for (int j = i - period; j < i; j++) {
                    if (prices[j] < low) {
                        low = prices[j];
                    }
                    if (prices[j] > high) {
                        high = prices[j];
                    }
                }

                lows[i % period] = low;
                highs[i % period] = high;

                double minLow = Double.MAX_VALUE;
                double maxHigh = Double.MIN_VALUE;

                for (int j = 0; j < period; j++) {
                    if (lows[j] < minLow) {
                        minLow = lows[j];
                    }
                    if (highs[j] > maxHigh) {
                        maxHigh = highs[j];
                    }
                }

                rsv = (p - minLow) / (maxHigh - minLow) * 100.0;
            }

            double k = 0.0;
            double d = 0.0;
            double j = 0.0;

            if (i == period) {
                k = 50.0;
                d = 50.0;
                j = 0.0;
            } else if (i > period) {
                k = ks[i - 1] * k1 + rsv * k2;
                d = ds[i - 1] * k1 + k * k2;
                j = 3.0 * k - 2.0 * d;
            }

            ks[i] = k;
            ds[i] = d;
            js[i] = j;
        }

        System.out.println("K: " + Arrays.toString(ks));
        System.out.println("D: " + Arrays.toString(ds));
        System.out.println("J: " + Arrays.toString(js));
    }
}

这段代码实现了 KDJ 的计算，其中用到了一个窗口期 period，一般取 9。KDJ 的计算中还需要用到两个参数 k1 和 k2，一般取 2/3 和 1/3。此外，还需要用到两个数组 lows 和 highs，分别保存最近 period 天的最低价和最高价。