请用c++代码构造牛顿差值多项式
时间: 2023-10-02 21:04:38 浏览: 35
以下是使用C++构建牛顿差值多项式的代码:
```cpp
#include <iostream>
#include <vector>
using namespace std;
// 计算差商
double divided_difference(int i, int j, const vector<double>& X, const vector<double>& Y) {
if (i == j) {
return Y[i];
} else {
return (divided_difference(i+1, j, X, Y) - divided_difference(i, j-1, X, Y)) / (X[j] - X[i]);
}
}
// 计算牛顿差值多项式
double newton_interpolation(double x, const vector<double>& X, const vector<double>& Y) {
double result = 0.0;
int n = X.size();
for (int i = 0; i < n; i++) {
double term = divided_difference(0, i, X, Y);
for (int j = 0; j < i; j++) {
term *= (x - X[j]);
}
result += term;
}
return result;
}
int main() {
vector<double> X = {1, 2, 4, 5};
vector<double> Y = {3, 5, 7, 10};
double x = 3;
cout << "f(" << x << ") = " << newton_interpolation(x, X, Y) << endl;
return 0;
}
```