C语言库modf()函数

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

int main () {
   double x, fractpart, intpart;

   x = 8.123456;
   fractpart = modf(x, &intpart);

   printf("Integral part = %lf\n", intpart);
   printf("Fraction Part = %lf \n", fractpart);

   return(0);
}