cosh, coshf, coshl - hyperbolic cosine function
Math library (
libm,
-lm)
#include <math.h>
double cosh(double x);
float coshf(float x);
long double coshl(long double x);
coshf(),
coshl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
These functions return the hyperbolic cosine of
x, which is defined
mathematically as:
cosh(x) = (exp(x) + exp(-x)) / 2
On success, these functions return the hyperbolic cosine of
x.
If
x is a NaN, a NaN is returned.
If
x is +0 or -0, 1 is returned.
If
x is positive infinity or negative infinity, positive infinity is
returned.
If the result overflows, a range error occurs, and the functions return
+
HUGE_VAL, +
HUGE_VALF, or +
HUGE_VALL, respectively.
See
math_error(7) for information on how to determine whether an error
has occurred when calling these functions.
The following errors can occur:
- Range error: result overflow
-
errno is set to ERANGE. An overflow
floating-point exception (FE_OVERFLOW) is raised.
For an explanation of the terms used in this section, see
attributes(7).
Interface |
Attribute |
Value |
cosh (), coshf (), coshl () |
Thread safety |
MT-Safe |
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4, 4.3BSD.
In glibc 2.3.4 and earlier, an overflow floating-point (
FE_OVERFLOW)
exception is not raised when an overflow occurs.
acosh(3),
asinh(3),
atanh(3),
ccos(3),
sinh(3),
tanh(3)