MODF(3) Library Functions Manual MODF(3)

modf, modff, modfl
extract signed integral and fractional values from floating-point number

Math Library (libm, -lm)

#include <math.h>

double
modf(double value, double *iptr);

float
modff(float value, float *iptr);

long double
modfl(long double value, long double *iptr);

The modf() function breaks the argument value into integral and fractional parts, each of which has the same sign as the argument. It stores the integral part as a double in the object pointed to by iptr.

The modf() function returns the signed fractional part of value.

frexp(3), ldexp(3), math(3)

The modf() function conforms to ANSI X3.159-1989 (“ANSI C89”).
March 7, 2016 NetBSD 9.0