sqrt, sqrtf, sqrtl - square root function

Attributes

       For an explanation of the terms used in this section, see attributes(7).
       ┌─────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                                                                   │ Attribute     │ Value   │
       ├─────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │ sqrt(), sqrtf(), sqrtl()                                                    │ Thread safety │ MT-Safe │
       └─────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

Description

       These functions return the nonnegative square root of x.

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.

History

       C99, POSIX.1-2001.

       The variant returning double also conforms to SVr4, 4.3BSD, C89.

Library

       Math library (libm, -lm)

Name

       sqrt, sqrtf, sqrtl - square root function

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.

Standards

       C11, POSIX.1-2008.

Synopsis

#include<math.h>doublesqrt(doublex);floatsqrtf(floatx);longdoublesqrtl(longdoublex);

   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