modf(3M) Mathematical Library Functions modf(3M)NAME
modf, modff, modfl - decompose floating-point number
SYNOPSIS
c99 [ flag... ] file... -lm [ library... ]
#include <math.h>
double modf(double x, double *iptr);
float modff(float x, float *iptr);
long double modfl(long double x, long double *iptr);
DESCRIPTION
These functions break the argument x into integral and fractional
parts, each of which has the same sign as the argument. It stores the
integral part as a double for the modf() function, a float for the
modff() function, or a long double for themodfl() function in the
object pointed to by iptr.
RETURN VALUES
Upon successful completion, these functions return the signed frac‐
tional part of x.
If x is NaN, a NaN is returned and *iptr is set to NaN.
If x is ±Inf, ±0 is returned and *iptr is set to ±Inf.
ERRORS
No errors are defined.
USAGE
These functions compute the function result and *iptr such that:
a = modf(x, &iptr) ;
x == a+*iptr ;
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Standard │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOfrexp(3M), isnan(3M), ldexp(3M), attributes(5), standards(5)SunOS 5.10 12 Jul 2006 modf(3M)