Question

I have following code for double comparision. Why I am getting not equal when I execute?

#include <iostream>
#include <cmath>
#include <limits> 

bool AreDoubleSame(double dFirstVal, double dSecondVal)
{
    return std::fabs(dFirstVal - dSecondVal) < std::numeric_limits<double>::epsilon();
}


int main()
{
double dFirstDouble = 11.304;
double dSecondDouble = 11.3043;

if(AreDoubleSame(dFirstDouble , dSecondDouble ) )
{
std::cout << "equal" << std::endl;
}
else
{
std::cout << "not equal" << std::endl;
}
}

Answer 1

The epsilon for 2 doubles is 2.22045e-016

By definition, epsilon is the difference between 1 and the smallest value greater than 1 that is
representable for the data type.

These differ by more than that and hence, it returns false

(Reference)