在本教程中,我们将讨论使用割线方法查找方程根的程序。
为此,我们将提供一个方程。我们的任务是使用迭代割线方法找到该方程的根。
#include <bits/stdc++.h>
using namespace std;
float f(float x) {
float f = pow(x, 3) + x - 1;
return f;
}
void secant(float x1, float x2, float E) {
float n = 0, xm, x0, c;
if (f(x1) * f(x2) < 0) {
do {
//计算中间值
x0 = (x1 * f(x2) - x2 * f(x1)) / (f(x2) - f(x1));
c = f(x1) * f(x0);
x1 = x2;
x2 = x0;
n++;
if (c == 0)
break;
xm = (x1 * f(x2) - x2 * f(x1)) / (f(x2) - f(x1));
} while (fabs(xm - x0) >= E);
cout << "Root of the given equation=" << x0 << endl;
cout << "No. of iterations = " << n << endl;
} else
cout << "Can not find a root in the given inteval";
}
int main() {
//初始化值
float x1 = 0, x2 = 1, E = 0.0001;
secant(x1, x2, E);
return 0;
}输出结果
Root of the given equation=0.682326 No. of iterations = 5