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   tanh    ( 3 )

функция гиперболического тангенса (hyperbolic tangent function)

Имя (Name)

tanh, tanhf, tanhl - hyperbolic tangent function

Синопсис (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 <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE


Описание (Description)

These functions return the hyperbolic tangent of x, which is
       defined mathematically as:

tanh(x) = sinh(x) / cosh(x)


Возвращаемое значение (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.


Ошибки (Error)

No errors occur.

Атрибуты (Attributes)

For an explanation of the terms used in this section, see
       attributes(7).

┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface Attribute Value │ ├──────────────────────────────────────┼───────────────┼─────────┤ │tanh(), tanhf(), tanhl() │ Thread safety │ MT-Safe │ └──────────────────────────────────────┴───────────────┴─────────┘


Стандарты (Conforming to)

C99, POSIX.1-2001, POSIX.1-2008.

The variant returning double also conforms to SVr4, 4.3BSD, C89.


Смотри также (See also)

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