SQRTSection: Linux Programmer's Manual (3)
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NAMEsqrt, sqrtf, sqrtl - square root function
#include <math.h> 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
DESCRIPTIONThese functions return the nonnegative square root of x.
RETURN VALUEOn 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.
ERRORSSee 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.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7).
|sqrt(), sqrtf(), sqrtl()||Thread safety||MT-Safe|
CONFORMING TOC99, POSIX.1-2001, POSIX.1-2008.
SEE ALSOcbrt(3), csqrt(3), hypot(3)
COLOPHONThis page is part of release 4.15 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/.
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