exp2(3) — Linux manual pages

Linux manual pages	Section 3

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);

Note

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
`exp2`(), `exp2f`(), `exp2l`():
`_XOPEN_SOURCE` >= 600 \|\| `_ISOC99_SOURCE`;
or cc `-std=c99`

	Note
	Link with `−lm`.

DESCRIPTION

The exp2() function returns 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.

CONFORMING TO

C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.

COLOPHON

This page is part of release 3.24 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.

  Copyright 1993 David Metcalfe (davidprism.demon.co.uk)
and Copyright 2008, Linux Foundation, written by Michael Kerrisk
    <mtk.manpagesgmail.com>

Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided that the
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Since the Linux kernel and libraries are constantly changing, this
manual page may be incorrect or out-of-date.  The author(s) assume no
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which is licensed free of charge, as they might when working
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Formatted or processed versions of this manual, if unaccompanied by
the source, must acknowledge the copyright and authors of this work.

References consulted:
    Linux libc source code
    Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
    386BSD man pages
Modified 1993-07-24 by Rik Faith (faithcs.unc.edu)
Modified 1995-08-14 by Arnt Gulbrandsen <agulbratroll.no>
Modified 2002-07-27 by Walter Harms
(walter.harmsinformatik.uni-oldenburg.de)