SIMPLE SOLUTIONS

COSH, COSHF, COSHL - reference manual online

Hyperbolic cosine function.

Chapter
2015-04-19
```COSH(3)                             Linux Programmer's Manual                             COSH(3)

NAME
cosh, coshf, coshl - hyperbolic cosine function

SYNOPSIS
#include <math.h>

double cosh(double x);
float coshf(float x);
long double coshl(long double x);

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

coshf(), coshl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
_POSIX_C_SOURCE >= 200112L;
or cc -std=c99

DESCRIPTION
These functions return the hyperbolic cosine of x, which is defined mathematically as:

cosh(x) = (exp(x) + exp(-x)) / 2

RETURN VALUE
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.

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:

Range error: result overflow
errno is set to ERANGE.  An overflow floating-point exception (FE_OVERFLOW) is
raised.

ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).

┌─────────────────────────┬───────────────┬─────────┐
│Interface                │ Attribute     │ Value   │
├─────────────────────────┼───────────────┼─────────┤
│cosh(), coshf(), coshl() │ Thread safety │ MT-Safe │
└─────────────────────────┴───────────────┴─────────┘
CONFORMING TO
C99, POSIX.1-2001, POSIX.1-2008.

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

BUGS
In glibc version 2.3.4 and earlier, an overflow floating-point (FE_OVERFLOW) exception is
not raised when an overflow occurs.