这个里面有严蔚敏老师c数据结构经典900例子

				#include 
				#include 
				
				void main (void)
				 {
				   double value = 1.2345;
				   double int_part;
				   double fraction;
				
				   fraction = modf(value, &int_part);
				
				   printf("Value %f Integer part %f Fraction %f\n",
				     value, int_part, fraction);
				 }