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

NAME         top

       cos, cosf, cosl - cosine function

SYNOPSIS         top

       #include <math.h>

       double cos(double x);
       float cosf(float x);
       long double cosl(long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       cosf(), cosl():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION         top

       These functions return the cosine of x, where x is given in radians.

RETURN VALUE         top

       On success, these functions return the cosine of x.

       If x is a NaN, a NaN is returned.

       If x is positive infinity or negative infinity, a domain error
       occurs, and a NaN is returned.

ERRORS         top

       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 an infinity
              errno is set to EDOM (but see BUGS).  An invalid floating-
              point exception (FE_INVALID) is raised.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see

       │Interface             Attribute     Value   │
       │cos(), cosf(), cosl() │ Thread safety │ MT-Safe │

CONFORMING TO         top

       C99, POSIX.1-2001, POSIX.1-2008.

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

BUGS         top

       Before version 2.10, the glibc implementation did not set errno to
       EDOM when a domain error occurred.

SEE ALSO         top

       acos(3), asin(3), atan(3), atan2(3), ccos(3), sin(3), sincos(3),

COLOPHON         top

       This page is part of release 4.10 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

                                 2016-03-15                           COS(3)

Pages that refer to this page: acos(3)asin(3)atan2(3)atan(3)dlopen(3)sin(3)sincos(3)tan(3)