TANH(3) Linux Programmer's Manual TANH(3)
NAME
tanh, tanhf, tanhl - hyperbolic tangent function
SYNOPSIS
#include <math.h>
double tanh(double x);
float tanhf(float x);
long double tanhl(long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
tanhf(), tanhl():
_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 tangent of x, which is defined
mathematically as:
tanh(x) = sinh(x) / cosh(x)
RETURN VALUE
On success, these functions return the hyperbolic tangent of x.
If x is a NaN, a NaN is returned.
If x is +0 (-0), +0 (-0) is returned.
If x is positive infinity (negative infinity), +1 (-1) is returned.
ERRORS
No errors occur.
ATTRIBUTES
For an explanation of the terms used in this section, see at-
tributes(7).
+-------------------------+---------------+---------+
|Interface | Attribute | Value |
+-------------------------+---------------+---------+
|tanh(), tanhf(), tanhl() | Thread safety | MT-Safe |
+-------------------------+---------------+---------+
CONFORMING TO
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
SEE ALSO
acosh(3), asinh(3), atanh(3), cosh(3), ctanh(3), sinh(3)
COLOPHON
This page is part of release 5.07 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/.
2017-09-15 TANH(3)