1TANH(3)                    Linux Programmer's Manual                   TANH(3)
2
3
4

NAME

6       tanh, tanhf, tanhl - hyperbolic tangent function
7

SYNOPSIS

9       #include <math.h>
10
11       double tanh(double x);
12       float tanhf(float x);
13       long double tanhl(long double x);
14
15       Link with -lm.
16
17   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
18
19       tanhf(), tanhl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600
20       || _ISOC99_SOURCE; or cc -std=c99
21

DESCRIPTION

23       The tanh() function returns the  hyperbolic  tangent  of  x,  which  is
24       defined mathematically as:
25
26           tanh(x) = sinh(x) / cosh(x)
27

RETURN VALUE

29       On success, these functions return the hyperbolic tangent of x.
30
31       If x is a NaN, a NaN is returned.
32
33       If x is +0 (-0), +0 (-0) is returned.
34
35       If x is positive infinity (negative infinity), +1 (-1) is returned.
36

ERRORS

38       No errors occur.
39

CONFORMING TO

41       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4,
42       4.3BSD, C89.
43

SEE ALSO

45       acosh(3), asinh(3), atanh(3), cosh(3), ctanh(3), sinh(3)
46

COLOPHON

48       This page is part of release 3.25 of the Linux  man-pages  project.   A
49       description  of  the project, and information about reporting bugs, can
50       be found at http://www.kernel.org/doc/man-pages/.
51
52
53
54                                  2008-08-05                           TANH(3)
Impressum