modf
return integral and fractional parts
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INTERFACE
#include <math.h>
double modf ( double value, double *iptr ) long modfl ( long double value, long double *iptr ) float modff ( float value, float *iptr )
DESCRIPTION
The modf functions break value into the integral and fractional parts, each of which has the same sign as the argument. They return the fractional part, and store the integral part (as a floating-point number) in the object pointed to by iptr.
Example 1
#include <math.h>
#include <stdio.h>
int main()
{
double x = 31415.9265, fractional, integer;
fractional = modf(x, &integer);
printf("%.4lf = %.4lf + %.4lf\n", x, integer, fractional);
return 0;
}Output:
31415.9265 = 31415.0000 + 0.9265SPECIAL VALUES
modf ( ±∞, iptr) returns ±0 and stores ±∞ in the object pointed to by iptr.
modf ( NaN, iptr) returns a NaN and stores a NaN in the object pointed to by iptr.
SEE ALSO
STANDARDS
The modf functions conform to ISO/IEC 9899:1999(E).