1. Computing & Technology
Linux / Unix Command: signbit
Command Library

NAME

signbit - test sign of a real floating point number  

SYNOPSIS

#include <math.h>

int signbit (X);

 

DESCRIPTION

`signbit' is a generic macro which can work on all real floating-point types. It returns a nonzero value if the value of X has its sign bit set.

This is not the same as `x < 0.0', because IEEE 754 floating point allows zero to be signed. The comparison `-0.0 < 0.0' is false, but `signbit (-0.0)' will return a nonzero value.  

CONFORMING TO

This function is defined in IEC 559 (and the appendix with recommended functions in IEEE 754/IEEE 854).  

SEE ALSO

copysign(3)


Important: Use the man command (% man) to see how a command is used on your particular computer.

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