table of contents
- stretch 4.10-2
- testing 4.16-2
- stretch-backports 4.16-1~bpo9+1
- unstable 4.16-2
|SQRT(3)||Linux Programmer's Manual||SQRT(3)|
NAME¶sqrt, sqrtf, sqrtl - square root function
double sqrt(double x); float sqrtf(float x); long double sqrtl(long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 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).
|sqrt (), sqrtf (), sqrtl ()||Thread safety||MT-Safe|
CONFORMING TO¶C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
SEE ALSO¶cbrt(3), csqrt(3), hypot(3)
COLOPHON¶This page is part of release 4.16 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.