table of contents
cosh(3) | Library Functions Manual | cosh(3) |
NAME¶
cosh, coshf, coshl - hyperbolic cosine function
LIBRARY¶
Math library (libm, -lm)
SYNOPSIS¶
#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
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 |
STANDARDS¶
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD.
BUGS¶
In glibc 2.3.4 and earlier, an overflow floating-point (FE_OVERFLOW) exception is not raised when an overflow occurs.
SEE ALSO¶
2023-02-05 | Linux man-pages 6.03 |