c语言编程定积分lnx,C语言用辛普森公式求lnx在0到100上的定积分的源程序

Question

c语言编程定积分lnx,C语言用辛普森公式求lnx在0到100上的定积分的源程序

Answer 1

有用点击右侧采纳即可！
代码如下：

#include <math.h>
#include <stdio.h>

double simpson(double (*f)(double), double a, double b, int n) {
    double h = (b - a) / (2 * n);
    double sum = f(a) + f(b);
    for (int i = 1; i <= n; i++) {
        double x = a + 2 * i * h;
        sum += 2 * f(x);
    }
    for (int i = 1; i < n; i++) {
        double x = a + (2 * i - 1) * h;
        sum += 4 * f(x);
    }
    return sum * h / 3;
}

double ln(double x) {
    return log(x);
}

double sinx(double x) {
    return sin(x);
}

int main() {
    int n = 10000;
    double a = 0, b = 100;
    double result = simpson(ln, a, b, n);
    printf("lnx在0到100上的定积分的近似值为: %.15lf\n", result);
    result = simpson(sinx, a, b, n);
    printf("sinx在0到100上的定积分的近似值为: %.15lf\n", result);
    return 0;
}