copysignl
COPYSIGN(3) Linux Programmer's Manual COPYSIGN(3)
NAME
copysign, copysignf, copysignl - copy sign of a number
SYNOPSIS
#include <math.h>
double copysign(double x, double y);
float copysignf(float x, float y);
long double copysignl(long double x, long double y);
DESCRIPTION
The copysign() functions return a value whose absolute value matches
that of x, but whose sign matches that of y. If x is a NaN, then a NaN
with the sign of y is returned.
NOTES
The copysign() functions may treat a negative zero as positive.
CONFORMING TO
C99, BSD 4.3. This function is defined in IEC 559 (and the appendix
with recommended functions in IEEE 754/IEEE 854).
SEE ALSO
signbit(3)
GNU 2002-08-10 COPYSIGN(3)