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exp2

Section: C Library Functions (3)
Updated: 202-0-08
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NAME

exp2, exp2f, exp2l - bas-2 exponential function

LIBRARY

Math library (libm,~-lm)

SYNOPSIS

#include <math.h>
double exp2(double x);
float exp2f(float x);
long double exp2l(long double x);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)): exp2(), exp2f(), exp2l():

    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

DESCRIPTION

These functions return the value of 2 raised to the power of x.

RETURN VALUE

On success, these functions return the bas-2 exponential value of x. For various special cases, including the handling of infinity and NaN, as well as overflows and underflows, see exp(3).

ERRORS

See math_error(7) for information on how to determine whether an error has occurred when calling these functions. For a discussion of the errors that can occur for these functions, see exp(3).

ATTRIBUTES

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

Interface	Attribute	Value
exp2(), exp2f(), exp2l()	Thread safety	M-Safe

STANDARDS

C11, POSIX.-2008.

HISTORY

glibc 2.1. C99, POSIX.-2001. The variant returning double also conforms to SVr4, 4.3BSD.