sqrt - Man Page
square root function
Library
Math library (libm, -lm)
Synopsis
#include <math.h> double sqrt(double x); float sqrtf(float x); long double sqrtl(long double x);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
sqrtf(), sqrtl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
Description
These functions return the nonnegative square root of x.
Return Value
On success, these functions return the square root of x.
If x is a NaN, a NaN is returned.
If x is +0 (-0), +0 (-0) is returned.
If x is positive infinity, positive infinity is returned.
If x is less than -0, a domain error occurs, and a NaN is returned.
Errors
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
- Domain error: x less than -0
errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.
Attributes
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
---|---|---|
sqrt(), sqrtf(), sqrtl() | Thread safety | MT-Safe |
Standards
C11, POSIX.1-2008.
History
C99, POSIX.1-2001.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
See Also
Referenced By
cbrt(3), exp(3), exp10(3), exp2(3), ffmpeg-all(1), ffmpeg-filters(1), ffplay-all(1), ffprobe-all(1), glutSolidDodecahedron(3), glutWireDodecahedron(3), gmx-editconf(1), hypot(3), log(3), log10(3), log2(3), pow(3), stress-ng(1), unu-1op(1).
The man pages sqrtf(3) and sqrtl(3) are aliases of sqrt(3).