COSH
Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
Page Index
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);
Link with -lm.
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
coshf(),
coshl():
-
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 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
|
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.
SEE ALSO
acosh(3),
asinh(3),
atanh(3),
ccos(3),
sinh(3),
tanh(3)
COLOPHON
This page is part of release 5.10 of the Linux
man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.