计算在指定点处多项式及其一阶导数值

//计算在指定点处多项式及其一阶导数值

#include <iostream>

using namespace std;

class horner

{

private:

int i, n;

double deriv, F, x;

double *a;

public:

horner()

{

deriv = 0;

}

void polynom();

~horner()

{

delete[] a;

}

};

void main()

{

horner poly;

poly.polynom();

}

void horner::polynom()

{

cout << "\n输入多项式的阶数：";

cin >> n;

a = new double[n+1];

cout << "\n输入多项式系数：a0 + a1 * x + a2 * x^2 + ..." << endl;

for (i = 0; i <= n; i++)

{

cout << "\n输入a[" << i << "] = ";

cin >> a[i];

}

cout << "\n输入计算多项式的所在点：";

cin >> x;

F = a
;

for (i = (n - 1); i >= 0; i--)

{

deriv = deriv * x + F;

F = F * x + a[i];

}

cout << "\n多项式在" << x << "点处的值 = " << F << endl;

cout << "\n多项式在" << x << "点处的导数值 = " << deriv << endl;

}