小编d-m*_*ney的帖子

我试图在for循环中做一个if语句,它给了我以下问题:"错误c2106:'=':左操作数必须是I值"旁边的每个if循环.

#include <iostream>
#include <cmath>
#include <vector>

using namespace std;

// Function of given equation
double function(double x)
{
    double result;
        result = 0.2+25*x-200*pow(x,2)+675*pow(x,3)-900*pow(x,4)+400*pow(x,5);
    return result;
}

int main()

{
    double boundup;         // Upper bound
    double bounddown;       // Lower bound
    double n;               // Number of intervals
    double step;            // Step size
    double fsimp;           // Simpson's rule
    double ftrap;           // Trapezoidal rule 

    cout << "Enter lower bound: " ;
    cin >> bounddown;

    cout << "Enter upper bound: " ;
    cin >> …