| Domain error: x is an infinity | errno is set to EDOM (but see BUGS). An invalid floating-point exception (FE_INVALID) is raised. |
NAME
cos, cosf, cosl - cosine function
LIBRARY
Math library (libm, -lm)
SYNOPSIS
#include <math.h>double cos(double \nx\n);\n
\nfloat cosf(float \nx\n);\n
\nlong double cosl(long double \nx\n);cosf(), cosl():
\n
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
\n
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
\n
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCEDESCRIPTION
These functions return the cosine of x, where x is given in radians.
RETURN VALUE
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
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
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
| cos (), cosf (), cosl () | Thread safety | MT-Safe |
STANDARDS
C11, POSIX.1-2008.
HISTORY
C89, POSIX.1-2001.
The variant returning double also conforms to SVr4, 4.3BSD.
BUGS
Before glibc 2.10, the glibc implementation did not set errno to EDOM when a domain error occurred.
SEE ALSO
acos(3), asin(3), atan(3), atan2(3), ccos(3), sin(3), sincos(3), tan(3)