COSHSection: Linux Programmer's Manual (3)
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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)):
DESCRIPTIONThe cosh() function returns 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.
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.
CONFORMING TOC99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD.
BUGSIn glibc version 2.3.4 and earlier, an overflow floating-point (FE_OVERFLOW) exception is not raised when an overflow occurs.
SEE ALSOacosh(3), asinh(3), atanh(3), ccos(3), sinh(3), tanh(3)
COLOPHONThis page is part of release 3.21 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.