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EXP2

Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
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NAME

exp2, exp2f, exp2l - base-2 exponential function

SYNOPSIS

#include <math.h>

double exp2(double x);
float exp2f(float x);
long double exp2l(long double x);

Link with -lm.

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 base-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).

VERSIONS

These functions first appeared in glibc in version 2.1.

ATTRIBUTES

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

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

CONFORMING TO

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

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

COLOPHON

This page is part of release 4.13 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.