NAME

copysign, copysignf, copysignl — copy sign

LIBRARY

Math Library (libm, -lm)

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(), copysignf() and copysignl() functions return x with its sign changed to y's.

SEE ALSO

fabs(3), fdim(3), ieee(3), math(3)

STANDARDS

The copysign(), copysignf(), and copysignl() routines conform to ISO/IEC 9899:1999 (“ISO C99”). They implement the Copysign function recommended by IEEE Std 754-1985.

HISTORY

The copysign(), copysignf(), and copysignl() functions appeared in 4.3BSD, FreeBSD 2.0, and FreeBSD 5.3, respectively.