copysign

copysign

Propagate the sign of a floating-point number to another

Portability: C99

SYNOPSIS
DESCRIPTION
RETURN VALUE
RELATED FUNCTIONS
SEE ALSO

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 function generates a floating-point result with the magnitude of the first argument and the sign of the second argument. In other words, it propagates the sign bit of the second argument to the first.

The function name copysignf should be used for float arguments, and copysignl for long double arguments. Alternately, if the header file tgmath.h is included, copysign may be used with any numeric argument type.

RETURN VALUE

The value of the first argument, with the sign of the second.

RELATED FUNCTIONS

signbit

SEE ALSO

"Mathematical Functions" in Chapter 2, "Function Categories"

Chapter Contents
Previous
Next
Top of Page