23/12/04 09:56:17.77 vGycO/bS.net
>#define PI 3.141592653589793238462643383279
ちなみに double に↑こんな値を入れても意味無いぞ
URLﾘﾝｸ(ideone.com)
#include <stdio.h>
#include <math.h>
#define M_PI acos(-1.0)
int main(void)
{
double r = M_PI / 6;
printf("sin(%.15f) = %.15f\n", r, sin(r));
r = asin(0.5);
printf("sin(%.15f) = %.15f\n", r, sin(r));
}