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   expl    ( 3 )

экспоненциальная функция с основанием e (base-e exponential function)

Имя (Name)

exp, expf, expl - base-e exponential function


Синопсис (Synopsis)

#include <math.h>

double exp(double x); float expf(float x); long double expl(long double x);

Link with -lm.

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

expf(), expl(): _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 value of e (the base of natural logarithms) raised to the power of x.


Возвращаемое значение (Return value)

On success, these functions return the exponential value of x.

If x is a NaN, a NaN is returned.

If x is positive infinity, positive infinity is returned.

If x is negative infinity, +0 is returned.

If the result underflows, a range error occurs, and zero is returned.

If the result overflows, a range error occurs, and the functions return +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL, respectively.


Ошибки (Error)

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, overflow errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised.

Range error, underflow errno is set to ERANGE. An underflow floating-point exception (FE_UNDERFLOW) is raised.


Атрибуты (Attributes)

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

┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface Attribute Value │ ├──────────────────────────────────────┼───────────────┼─────────┤ │exp(), expf(), expl() │ 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)

cbrt(3), cexp(3), exp10(3), exp2(3), expm1(3), sqrt(3)