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():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
           or cc -std=c99

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 attributes(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

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       http://www.kernel.org/doc/man-pages/.

                                                   2015-04-19                                            TANH(3)