Sin함수 만들기(II)

#include <stdio.h>
#include <math.h>

double SigAngle(int x);
int main()
{
    int d=0;
    for(d=0;d<360;d=d+20)
    {
     printf("Comparison %25.20f vs %25.20f\n",SigAngle(d), sin(d/180.0));
    }
}

double SigAngle(int x)
{
    int i;
    double y, sum;
    double angle;
    angle = (x%360)/180.0;
 
    y = angle; 
    sum = angle;
    for(i=1; i<=8; i++)
    {
        sum = sum*(-1)*angle*angle/((2*i)*(2*i+1));
        y = y + sum;
    }
    return y;
}