cos, cosf, cosl - cosine function
#include <math.h> double cos(double x); float cosf(float x); long double cosl(long double x);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
These functions return the cosine of
given in radians.
On success, these functions return the cosine of
x is a NaN, a NaN is returned.
x is positive infinity or negative infinity, a domain
error occurs, and a NaN is returned.
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
xis an infinity
errno is set to EDOM (but see BUGS). An
invalid floating-point exception (FE_INVALID) is
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4,
Before version 2.10, the glibc implementation did not set
errno to EDOM when a domain error
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