COS(3M) Mathematical Library Functions COS(3M)

cos, cosf, cosl - cosine function

c99 [ flag... ] file... -lm [ library... ]
#include <math.h>
double cos(double x);

float cosf(float x);

long double cosl(long double x);

These functions compute the cosine of x, measured in radians.

Upon successful completion, these functions return the cosine of x.

If x is NaN, NaN is returned.

If x is +0, 1.0 is returned.

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

These functions will fail if:

Domain Error

The x argument is ±Inf.

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

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.

See attributes(7) for descriptions of the following attributes:

Interface Stability Standard
MT-Level MT-Safe

math.h(3HEAD), acos(3M), feclearexcept(3M), fetestexcept(3M), isnan(3M), sin(3M), tan(3M), attributes(7), standards(7)

July 12, 2006 SunOS 5.11