#include <stdio.h>
#include <math.h>
int main(int argc, char **argv)
{
printf("atan2(1, 1) = %.6f\n", atan2(1, 1));
printf("atan2(1, -1) = %.6f\n", atan2(1, -1));
printf("atan2(-1, 1) = %.6f\n", atan2(-1, 1));
printf("atan2(-1, -1) = %.6f\n", atan2(-1, -1));
return 0;
}
/*
run:
atan2(1, 1) = 0.785398
atan2(1, -1) = 2.356194
atan2(-1, 1) = -0.785398
atan2(-1, -1) = -2.356194
*/