weird output using cos

Hi,

using the following code:

Code:

---


#include <cmath>
#include <iostream>

using namespace std;

int main(){

double z = 0;
double z2 = 180;
z = cos(z2);

cout << z;

return 0;
}

---

The result should be -1 but it gives me out a value of -0,59..

Anyone knows the problem?


Thanks in advance!

~Jan

the argument to cos isn't in degrees, it's in radians
Convert degrees to radians using:
radian=degree*(pi/180)

so

Code:

---

#define _USE_MATH_DEFINES //to define M_PI
#include <math>
#include <iostream>

using namespace std;

int main(){

double z = 0;
double z2 = 180;
z2*=(M_PI/180.f) //z2 is now 180 deg in radians
z = cos(z2);

cout << z;

return 0;
}

---

/btq :)