JAVA实现开根号的两种方式：二分法以及牛顿迭代法

public class demo {
    public static void main(String[] args) {
        System.out.println("———— 二分法计算根号 ————");
        double result_a = math_Method.mathematicalDichotomy(99999999L, 1, 2, 2);
        double result_b = math_Method.mathematicalDichotomy(99999999L, 2, 3, 8);
        if (result_a + result_a - result_b >= 0 || result_b - (result_a + result_a) <= 0) {
            System.out.println("综上 ： √2 + √2 = √8");
        } else {
            System.out.println("综上 ： √2 + √2 ≠ √8");
        }
        System.out.println("—— 牛顿迭代法计算根号 ——");
        double result_c = math_Method.Newton_iterative_method(2, 99999999L);
        double result_d = math_Method.Newton_iterative_method(8, 99999999L);
        if (result_c + result_c - result_d >= 0 || result_d - (result_c + result_c) <= 0) {
            System.out.println("综上 ： √2 + √2 = √8");
        } else {
            System.out.println("综上 ： √2 + √2 ≠ √8");
        }
    }
}
class math_Method {
    public static double mathematicalDichotomy(
            long times, double low, double high, double number_Of_Required__square) {
        double average = 0, sum;
        for (int x = 0; x < times; x++) {
            average = (low + high) / 2;
            sum = average * average;
            if (sum > number_Of_Required__square)
                high = average;
            else
                low = average;
        }
        System.out.println("√" + number_Of_Required__square + " = " + average);
        return average;
    }
    public static double Newton_iterative_method(double number_Of_Required__square, long times) {
        /* 牛顿迭代公式：X(n+1)=(X(n)+a/X(n))/2 */
        double X1 = number_Of_Required__square / 2;
        double X_n_jia_1 = 0;
        for (int i = 0; i <= times; i++) {
            X_n_jia_1 = (X1 + number_Of_Required__square / X1) / 2;
            if (X_n_jia_1 - X1 >= 0 & X_n_jia_1 - X1 <= 0.00000001) {
                System.out.println("√" + number_Of_Required__square + " = " + X_n_jia_1);
                break;
            } else if (X_n_jia_1 - X1 <= 0 & X_n_jia_1 - X1 >= 0.00000001) {
                System.out.println("√" + number_Of_Required__square + " = " + X_n_jia_1);
                break;
            } else {
                X1 = X_n_jia_1;
            }
        }
        return X_n_jia_1;
    }
}