[linuxjm/LDP_man-pages.git] / draft / man3 / scalb.3

.\" Copyright 2004 Andries Brouwer <aeb@cwi.nl>.
.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
.\"     <mtk.manpages@gmail.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
.\" 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.\" manual page may be incorrect or out-of-date.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.
.\"
.\" Japanese Version Copyright (c) 2005 Yuichi SATO all rights reserved.
.\" and Copyright (c) 2008 Akihiro MOTOKI
.\" Translated Tue Feb  1 07:25:51 JST 2005
.\"         by Yuichi SATO <ysato444@yahoo.co.jp>
.\" Updated 2008-09-16, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.TH SCALB 3 2010-09-20 "" "Linux Programmer's Manual"
.\"O .SH NAME
.SH ̾Á°
.\"O scalb, scalbf, scalbl \- multiply floating-point number
.\"O by integral power of radix (OBSOLETE)
scalb, scalbf, scalbl \- ÉâÆ°¾®¿ôÅÀ¿ô¤ËÀ°¿ô¤Ç¤¢¤ë´ð¿ô¤ÎÎß¾è¤ò³Ý¤±¤ë (ÇÑ»ßͽÄê)
.\"O .SH SYNOPSIS
.SH ½ñ¼°
.B #include <math.h>
.sp
.BI "double scalb(double " x ", double " exp );
.br
.BI "float scalbf(float " x ", double " exp );
.br
.BI "long double scalbl(long double " x ", double " exp );
.sp
.\"O Link with \fI\-lm\fP.
\fI\-lm\fP ¤Ç¥ê¥ó¥¯¤¹¤ë¡£
.sp
.in -4n
.\"O Feature Test Macro Requirements for glibc (see
.\"O .BR feature_test_macros (7)):
glibc ¸þ¤±¤Îµ¡Ç½¸¡ºº¥Þ¥¯¥í¤ÎÍ×·ï
.RB ( feature_test_macros (7)
»²¾È):
.in
.sp
.ad l
.BR scalb ():
.RS 4
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
.RE
.br
.BR scalbf (),
.BR scalbl ():
.RS 4
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600
.RE
.ad b
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O These functions multiply their first argument
.\"O .I x
.\"O by
.\"O .B FLT_RADIX
.\"O (probably 2)
.\"O to the power of
.\"O .IR exp ,
.\"O that is:
¤³¤ì¤é¤Î´Ø¿ô¤ÏºÇ½é¤Î°ú¤­¿ô
.I x
¤Ë
.B FLT_RADIX
¤Î
.I exp
¾è¤ò³Ý¤±¤ë
.RB ( FLT_RADIX
¤Ï¤ª¤½¤é¤¯ 2 ¤Ç¤¢¤ë)¡£¤Ä¤Þ¤ê¡¢°Ê²¼¤Î¼°¤ÎÃͤòÊÖ¤¹¡£
.nf

    x * FLT_RADIX ** exp
.fi

.\"O The definition of
.\"O .B FLT_RADIX
.\"O can be obtained by including
.\"O .I <float.h> .
.B FLT_RADIX
¤ÎÄêµÁ¤Ï
.I <float.h>
¤ò¥¤¥ó¥¯¥ë¡¼¥É¤¹¤ë¤³¤È¤ÇÆÀ¤é¤ì¤ë¡£
.\"O .\" not in /usr/include but in a gcc lib
.\" /usr/include ¤Ç¤Ï¤Ê¤¯¡¢gcc ¤Î lib ¤Ë¤¢¤ë¡£
.\"O .SH RETURN VALUE
.SH ÊÖ¤êÃÍ
.\"O On success, these functions return \fIx\fP * \fBFLT_RADIX\fP ** \fIexp\fP.
À®¸ù¤¹¤ë¤È¡¢¤³¤ì¤é¤Î´Ø¿ô¤Ï \fIx\fP * \fBFLT_RADIX\fP ** \fIexp\fP ¤òÊÖ¤¹¡£

.\"O If
.\"O .I x
.\"O or
.\"O .I exp
.\"O is a NaN, a NaN is returned.
.I x
¤«
.I exp
¤¬ NaN ¤Î¾ì¹ç¡¢NaN ¤¬ÊÖ¤µ¤ì¤ë¡£

.\"O If
.\"O .I x
.\"O is positive infinity (negative infinity),
.\"O and
.\"O .I exp
.\"O is not negative infinity,
.\"O positive infinity (negative infinity) is returned.
.I x
¤¬Àµ¤Î̵¸ÂÂç (Éé¤Î̵¸ÂÂç) ¤Ç
.I exp
¤¬Éé¤Î̵¸ÂÂç¤Ç¤Ê¤¤¾ì¹ç¡¢Àµ¤Î̵¸ÂÂç (Éé¤Î̵¸ÂÂç) ¤¬ÊÖ¤µ¤ì¤ë¡£

.\"O If
.\"O .I x
.\"O is +0 (\-0), and
.\"O .I exp
.\"O is not positive infinity, +0 (\-0) is returned.
.I x
¤¬ +0 (\-0) ¤Ç
.I exp
¤¬Àµ¤Î̵¸ÂÂç¤Ç¤Ê¤¤¾ì¹ç¡¢+0 (\-0) ¤¬ÊÖ¤µ¤ì¤ë¡£

.\"O If
.\"O .I x
.\"O is zero, and
.\"O .I exp
.\"O is positive infinity,
.\"O a domain error occurs, and
.\"O a NaN is returned.
.I x
¤¬¥¼¥í¤Ç
.I exp
¤¬Àµ¤Î̵¸ÂÂç¤Î¾ì¹ç¡¢Îΰ襨¥é¡¼ (domain error) ¤¬È¯À¸¤·¡¢
NaN ¤¬ÊÖ¤µ¤ì¤ë¡£

.\"O If
.\"O .I x
.\"O is an infinity,
.\"O and
.\"O .I exp
.\"O is negative infinity,
.\"O a domain error occurs, and
.\"O a NaN is returned.
.I x
¤¬Ìµ¸ÂÂç¤Ç
.I exp
¤¬Éé¤Î̵¸ÂÂç¤Î¾ì¹ç¡¢Îΰ襨¥é¡¼ (domain error) ¤¬È¯À¸¤·¡¢
NaN ¤¬ÊÖ¤µ¤ì¤ë¡£

.\"O If the result overflows,
.\"O a range error occurs,
.\"O and the functions return
.\"O .BR HUGE_VAL ,
.\"O .BR HUGE_VALF ,
.\"O or
.\"O .BR HUGE_VALL ,
.\"O respectively, with a sign the same as
.\"O .IR x .
·ë²Ì¤¬¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤¹¤ë¾ì¹ç¡¢
ÈÏ°Ï¥¨¥é¡¼ (range error) ¤¬È¯À¸¤·¡¢
³Æ´Ø¿ô¤Ï¤½¤ì¤¾¤ì
.BR HUGE_VAL ,
.BR HUGE_VALF ,
.BR HUGE_VALL
¤òÊÖ¤¹¡£Éä¹æ¤Ï
.I x
¤ÈƱ¤¸¤Ë¤Ê¤ë¡£

.\"O If the result underflows,
.\"O a range error occurs,
.\"O and the functions return zero, with a sign the same as
.\"O .IR x .
·ë²Ì¤¬¥¢¥ó¥À¡¼¥Õ¥í¡¼¤¹¤ë¾ì¹ç¡¢ÈÏ°Ï¥¨¥é¡¼¤¬È¯À¸¤·¡¢
³Æ´Ø¿ô¤Ï 0 ¤òÊÖ¤¹¡£Éä¹æ¤Ï
.I x
¤ÈƱ¤¸¤Ë¤Ê¤ë¡£
.\"O .SH ERRORS
.SH ¥¨¥é¡¼
.\"O See
.\"O .BR math_error (7)
.\"O for information on how to determine whether an error has occurred
.\"O when calling these functions.
¤³¤ì¤é¤Î´Ø¿ô¤ò¸Æ¤Ó½Ð¤·¤¿ºÝ¤Ë¥¨¥é¡¼¤¬È¯À¸¤·¤¿¤«¤ÎȽÄêÊýË¡¤Ë¤Ä¤¤¤Æ¤Î¾ðÊó¤Ï
.BR math_error (7)
¤ò»²¾È¤Î¤³¤È¡£
.PP
.\"O The following errors can occur:
°Ê²¼¤Î¥¨¥é¡¼¤¬È¯À¸¤¹¤ë²ÄǽÀ­¤¬¤¢¤ë¡£
.TP
.\"O Domain error: \fIx\fP is 0, and \fIexp\fP is positive infinity, \
.\"O or \fIx\fP is positive infinity and \fIexp\fP is negative infinity \
.\"O and the other argument is not a NaN
.\"Omotoki: °ú¤­¿ô¤Ï x, exp ¤ÎÆó¤Ä¤ÇξÊý¤È¤â¾ò·ï¤Ë´Þ¤Þ¤ì¤Æ¤¤¤ë¤Î¤Ç¡¢
.\"Omotoki: ¾¤Î°ú¤­¿ô¤Ë´Ø¤¹¤ëµ­½Ò¤Ï°ÕÌ£¤¬¤Ê¤¤¤È»×¤ï¤ì¤ë¡£ÏÂÌõ¤Ç¤Ï¾Êά¤¹¤ë¡£
Îΰ襨¥é¡¼ (domain error): \fIx\fP ¤¬ 0 ¤Ç \fIexp\fP ¤¬Àµ¤Î̵¸ÂÂç¡¢\
¤Þ¤¿¤Ï \fIx\fP ¤¬Àµ¤Î̵¸ÂÂç¤Ç \fIexp\fP ¤¬Éé¤Î̵¸ÂÂç
.\" .I errno
.\" is set to
.\" .BR EDOM .
.\"O An invalid floating-point exception
.\"O .RB ( FE_INVALID )
.\"O is raised.
ÉÔÀµ (invalid) ÉâÆ°¾®¿ôÅÀÎã³°
.RB ( FE_INVALID )
¤¬¾å¤¬¤ë¡£
.TP
.\"O Range error, overflow
ÈÏ°Ï¥¨¥é¡¼ (range error)¡¢¥ª¡¼¥Ð¡¼¥Õ¥í¡¼
.\" .I errno
.\" is set to
.\" .BR ERANGE .
.\"O An overflow floating-point exception
.\"O .RB ( FE_OVERFLOW )
.\"O is raised.
¥ª¡¼¥Ð¡¼¥Õ¥í¡¼ÉâÆ°¾®¿ôÅÀÎã³°
.RB ( FE_OVERFLOW )
¤¬¾å¤¬¤ë¡£
.TP
.\"O Range error, underflow
ÈÏ°Ï¥¨¥é¡¼ (range error)¡¢¥¢¥ó¥À¡¼¥Õ¥í¡¼
.\" .I errno
.\" is set to
.\" .BR ERANGE .
.\"O An underflow floating-point exception
.\"O .RB ( FE_UNDERFLOW )
.\"O is raised.
¥¢¥ó¥À¡¼¥Õ¥í¡¼ÉâÆ°¾®¿ôÅÀÎã³°
.RB ( FE_UNDERFLOW )
¤¬¾å¤¬¤ë¡£
.PP
.\"O These functions do not set
.\"O .IR errno .
¤³¤ì¤é¤Î´Ø¿ô¤Ï
.I errno
¤òÀßÄꤷ¤Ê¤¤¡£
.\" FIXME . Is it intentional that these functions do not set errno?
.\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6803
.\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6804
.\"O .SH "CONFORMING TO"
.SH ½àµò
.\"O .BR scalb ()
.\"O is specified in POSIX.1-2001, but marked obsolescent.
.\"O POSIX.1-2008 removes the specification of
.\"O .BR scalb (),
.\"O recommending the use of
.\"O .BR scalbln (3),
.\"O .BR scalblnf (3),
.\"O or
.\"O .BR scalblnl (3)
.\"O instead.
.\"O The
.\"O .BR scalb ()
.\"O function is from 4.3BSD.
.BR scalb ()
¤Ï POSIX.1-2001 ¤Çµ¬Äꤵ¤ì¤Æ¤¤¤ë¤¬¡¢ÇÑ»ßͽÄê¤È¤µ¤ì¤Æ¤¤¤ë¡£
POSIX.1-2008 ¤Ç¤Ï
.BR scalb ()
¤Î»ÅÍͤϺï½ü¤µ¤ì¤Æ¤ª¤ê¡¢Âå¤ï¤ê¤Ë
.BR scalbln (3),
.BR scalblnf (3),
.BR scalblnl (3)
¤Î»ÈÍѤ¬¿ä¾©¤µ¤ì¤Æ¤¤¤ë¡£
.BR scalb ()
´Ø¿ô¤Ï 4.3BSD ¤ËͳÍ褹¤ë¡£

.\"O .BR scalbf ()
.\"O and
.\"O .BR scalbl ()
.\"O are unstandardized;
.\"O .BR scalbf ()
.\"O is nevertheless present on several other systems
.BR scalbf ()
¤È
.BR scalbl ()
¤Ïɸ½à²½¤µ¤ì¤Æ¤¤¤Ê¤¤¡£
¤½¤ì¤Ë¤â´Ø¤ï¤é¤º¡¢
.BR scalbf ()
¤Ï¤¤¤¯¤Ä¤«¤Î¾¤Î¥·¥¹¥Æ¥à¤Ë¸ºß¤¹¤ë¡£
.\" Looking at header files: scalbf() is present on the
.\" BSDs, Tru64, HP-UX 11, Irix 6.5; scalbl() is on HP-UX 11 and Tru64.
.\"O .SH "SEE ALSO"
.SH ´ØÏ¢¹àÌÜ
.BR ldexp (3),
.BR scalbln (3)