Why is std::sin() and std::cos() slower than sin() and cos()?

Question

Test code:

#include 
#include 

const int N = 4096;
const float PI = 3.1415926535897932384626;

float cosine[N][N];
float sine[N][         


        

Answer 1

You're using a different overload:

Try

        double angle = i*j*2*PI/N;
        cosine[i][j] = cos(angle);
        sine[i][j] = sin(angle);

it should perform the same with or without using namespace std;