# acosl(3) [centos man page]

ACOS(3) Linux Programmer's Manual ACOS(3)NAME

acos, acosf, acosl - arc cosine functionSYNOPSIS

#include <math.h> double acos(double x); float acosf(float x); long double acosl(long double x); Link withFeature Test Macro Requirements for glibc (see feature_test_macros(7)): acosf(), acosl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L; or cc-lm.-std=c99DESCRIPTION

The acos() function calculates the arc cosine of x; that is the value whose cosine is x.RETURN VALUE

On success, these functions return the arc cosine of x in radians; the return value is in the range [0, pi]. If x is a NaN, a NaN is returned. If x is +1, +0 is returned. If x is positive infinity or negative infinity, a domain error occurs, and a NaN is returned. If x is outside the range [, 1], a domain error occurs, and a NaN is returned.-1ERRORS

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 is outside the range [, 1] errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.-1CONFORMING TO

C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.SEE ALSO

asin(3), atan(3), atan2(3), cacos(3), cos(3), sin(3), tan(3)COLOPHON

This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. 2010-09-20 ACOS(3)

## Check Out this Related Man Page

ACOS(3) Linux Programmer's Manual ACOS(3)NAME

acos, acosf, acosl - arc cosine functionSYNOPSIS

#include <math.h> double acos(double x); float acosf(float x); long double acosl(long double x); Link withFeature Test Macro Requirements for glibc (see feature_test_macros(7)): acosf(), acosl(): _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE-lm.DESCRIPTION

These functions calculate the arc cosine of x; that is the value whose cosine is x.RETURN VALUE

On success, these functions return the arc cosine of x in radians; the return value is in the range [0, pi]. If x is a NaN, a NaN is returned. If x is +1, +0 is returned. If x is positive infinity or negative infinity, a domain error occurs, and a NaN is returned. If x is outside the range [, 1], a domain error occurs, and a NaN is returned.-1ERRORS

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 is outside the range [, 1] errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.-1ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7). +-------------------------+---------------+---------+ |Interface | Attribute | Value | +-------------------------+---------------+---------+ |acos(), acosf(), acosl() | 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

asin(3), atan(3), atan2(3), cacos(3), cos(3), sin(3), tan(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 ACOS(3)