fabs(3) | Library Functions Manual | fabs(3) |
fabs, fabsf, fabsl - absolute value of floating-point number
Math library (libm, -lm)
#include <math.h>
double fabs(double x); float fabsf(float x); long double fabsl(long double x);
fabsf(), fabsl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
These functions return the absolute value of the floating-point number x.
These functions return the absolute value of x.
If x is a NaN, a NaN is returned.
If x is -0, +0 is returned.
If x is negative infinity or positive infinity, positive infinity is returned.
No errors occur.
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
fabs (), fabsf (), fabsl () | Thread safety | MT-Safe |
C11, POSIX.1-2008.
C99, POSIX.1-2001.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
abs(3), cabs(3), ceil(3), floor(3), labs(3), rint(3)
2023-10-31 | Linux man-pages 6.7 |