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NAME
sqrt, sqrtf, sqrtl - square root function
SYNOPSIS
#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)):
sqrtf(), sqrtl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99
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 │
└──────────────────────────┴───────────────┴─────────┘
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
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information about reporting bugs, and the latest version of this page, can be found at
http://www.kernel.org/doc/man-pages/.
2015-04-19 SQRT(3)