sqrt(3) [xfree86 man page]

SQRT(3) 						     Linux Programmer's Manual							   SQRT(3)

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():
	   _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).

       +-------------------------+---------------+---------+
       |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

       This  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/.

								    2017-09-15								   SQRT(3)

sqrt(3M)						  Mathematical Library Functions						  sqrt(3M)

NAME

       sqrt, sqrtf, sqrtl - square root function

SYNOPSIS

       c99 [ flag... ] file... -lm [ library... ]
       #include <math.h>

       double sqrt(double x);

       float sqrtf(float x);

       long double sqrtl(long double x);

DESCRIPTION

       These functions compute the square root of their argument x.

RETURN VALUES

       Upon successful completion, these functions return the square root of x.

       For finite values of x < -0, a domain error occurs and either a NaN (if supported) or an implementation-defined value is returned.

       If x is NaN, a NaN is returned.

       If x is +-0 or +Inf, x is returned.

       If x is -Inf, a domain error occurs and a NaN is returned.

ERRORS

       These functions will fail if:

       Domain Error    The finite value of x is < -0 or x is -Inf.

		       If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, the invalid floating-point exception is raised.

		       The sqrt() function sets errno to EDOM if the value of x is negative.

USAGE

       An  application	wanting  to  check  for  exceptions should call feclearexcept(FE_ALL_EXCEPT) before calling these functions. On return, if
       fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an exception  has  been  raised.  An  application  should
       either examine the return value or check the floating point exception flags to detect exceptions.

       An  application	can  also  set	errno  to 0 before calling sqrt(). On return, if errno is non-zero, an error has occurred. The sqrtf() and
       sqrtl() functions do not set errno.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       feclearexcept(3M), fetestexcept(3M), isnan(3M), math.h(3HEAD), attributes(5), standards(5)

SunOS 5.11							    12 Jul 2006 							  sqrt(3M)