Copyright 1993 David Metcalfe (firstname.lastname@example.org) and Copyright 2008, Linux Foundation, written by Michael Kerrisk <email@example.com> %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting ...
NAMEcosh, coshf, coshl - hyperbolic cosine function
#include <math.h> double cosh(double x);
float coshf(float x);
long double coshl(long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
_POSIX_C_SOURCE >= 200112L;
or cc -std=c99
DESCRIPTIONThese functions return the hyperbolic cosine of x, which is defined mathematically as:
cosh(x) = (exp(x) + exp(-x)) / 2
RETURN VALUEOn 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.
ERRORSSee 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.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7).
|cosh(), coshf(), coshl()||Thread safety||MT-Safe|
CONFORMING TOC99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD.