.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk .\" .\" .\" 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 .\" entire resulting derived work is distributed under the terms of a .\" permission notice identical to this one. .\" .\" Since the Linux kernel and libraries are constantly changing, this .\" manual page may be incorrect or out-of-date. The author(s) assume no .\" responsibility for errors or omissions, or for damages resulting from .\" the use of the information contained herein. The author(s) may not .\" have taken the same level of care in the production of this manual, .\" which is licensed free of charge, as they might when working .\" professionally. .\" .\" 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 (faith@cs.unc.edu) .\" Modified 1995-08-14 by Arnt Gulbrandsen .\" Modified 2002-07-27 by Walter Harms .\" (walter.harms@informatik.uni-oldenburg.de) .\" .\" Japanese Version Copyright (c) 2003 Akihiro MOTOKI .\" all rights reserved. .\" Translated Tue Sep 23 20:27:35 JST 2003 .\" by Akihiro MOTOKI .\" .TH EXP2 3 2010-09-20 "" "Linux Programmer's Manual" .\"O .SH NAME .SH 名前 .\"O exp2, exp2f, exp2l \- base-2 exponential function exp2, exp2f, exp2l \- 底が 2 の指数関数 .\"O .SH SYNOPSIS .SH 書式 .nf .B #include .sp .BI "double exp2(double " x ); .br .BI "float exp2f(float " x ); .br .BI "long double exp2l(long double " x ); .fi .sp .\"O Link with \fI\-lm\fP. \fI-lm\fP でリンクする。 .sp .in -4n .\"O Feature Test Macro Requirements for glibc (see .\"O .BR feature_test_macros (7)): glibc 向けの機能検査マクロの要件 .RB ( feature_test_macros (7) 参照): .in .sp .ad l .BR exp2 (), .BR exp2f (), .BR exp2l (): .RS 4 _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE\ >=\ 200112L; .br or .I cc\ -std=c99 .RE .ad b .\"O .SH DESCRIPTION .SH 説明 .\"O The .\"O .BR exp2 () .\"O function returns the value of 2 .\"O raised to the power of \fIx\fP. .BR exp2 () 関数は 2 の \fIx\fP 乗の値を返す。 .\"O .SH RETURN VALUE .SH 返り値 .\"O On success, these functions return the base-2 exponential value of .\"O .IR x . 成功すると、これらの関数は 2 の .I x 乗を返す。 .\"O For various special cases, including the handling of infinity and NaN, .\"O as well as overflows and underflows, see .\"O .BR exp (3). 無限大や NaN の扱いや、オーバーフローとアンダーフローなどの さまざまな特別な状況については、 .BR exp (3) を参照のこと。 .\"O .SH ERRORS .SH エラー .\"O See .\"O .BR math_error (7) .\"O for information on how to determine whether an error has occurred .\"O when calling these functions. これらの関数を呼び出した際にエラーが発生したかの判定方法についての情報は .BR math_error (7) を参照のこと。 .\"O For a discussion of the errors that can occur for these functions, see .\"O .BR exp (3). これらの関数で発生するエラーについては、 .BR exp (3) を参照のこと。 .\"O .SH VERSIONS .SH バージョン .\"O These functions first appeared in glibc in version 2.1. これらの関数は glibc バージョン 2.1 で初めて登場した。 .\"O .SH "CONFORMING TO" .SH 準拠 C99, POSIX.1-2001. .\"O The variant returning .\"O .I double .\"O also conforms to .\"O SVr4, 4.3BSD, C89. .I double 版の関数は SVr4, 4.3BSD, C89 にも準拠している。 .\"O .SH "SEE ALSO" .SH 関連項目 .BR cbrt (3), .BR cexp2 (3), .BR exp (3), .BR exp10 (3), .BR sqrt (3)