sqrt, sqrtf, sqrtl - square root function
#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)):
These functions return the nonnegative square root of
On success, these functions return the square root of
x is a NaN, a NaN is returned.
x is +0 (-0), +0 (-0) is returned.
x is positive infinity, positive infinity is
x is less than -0, a domain error occurs, and a NaN is
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
xless than -0
errno is set to EDOM. An invalid
floating-point exception (FE_INVALID) is raised.
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4, 4.3BSD,
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