sin, cos, tan and rounding error

Question

I\'m doing some trigonometry calculations in C/C++ and am running into problems with rounding errors. For example, on my Linux system:

#include 

        

Answer 1

I get the exact same result on my system - I'd say it is close enough

I would solve the problem by changing the format string to "%f\n" :)

However, this gives you a "better" result, or at least on my system it does give -3.661369e-245

#include 
#include 

int main(int argc, char *argv[]) {
    printf("%e\n", (long double)sin(M_PI));
    return 0;
}