xref: /freebsd/lib/libc/gen/ldexp.3 (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
1.\" Copyright (c) 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" This code is derived from software contributed to Berkeley by
5.\" the American National Standards Committee X3, on Information
6.\" Processing Systems.
7.\"
8.\" Redistribution and use in source and binary forms, with or without
9.\" modification, are permitted provided that the following conditions
10.\" are met:
11.\" 1. Redistributions of source code must retain the above copyright
12.\"    notice, this list of conditions and the following disclaimer.
13.\" 2. Redistributions in binary form must reproduce the above copyright
14.\"    notice, this list of conditions and the following disclaimer in the
15.\"    documentation and/or other materials provided with the distribution.
16.\" 3. All advertising materials mentioning features or use of this software
17.\"    must display the following acknowledgement:
18.\"	This product includes software developed by the University of
19.\"	California, Berkeley and its contributors.
20.\" 4. Neither the name of the University nor the names of its contributors
21.\"    may be used to endorse or promote products derived from this software
22.\"    without specific prior written permission.
23.\"
24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34.\" SUCH DAMAGE.
35.\"
36.\"     @(#)ldexp.3	8.2 (Berkeley) 4/19/94
37.\" $FreeBSD$
38.\"
39.Dd January 23, 2005
40.Dt LDEXP 3
41.Os
42.Sh NAME
43.Nm ldexp
44.Nd multiply floating-point number by integral power of 2
45.Sh LIBRARY
46.Lb libm
47.Sh SYNOPSIS
48.In math.h
49.Ft double
50.Fn ldexp "double x" "int exp"
51.Ft float
52.Fn ldexpf "float x" "int exp"
53.Sh DESCRIPTION
54The
55.Fn ldexp
56and
57.Fn ldexpf
58functions multiply a floating-point number by an integral
59power of 2.
60.Sh RETURN VALUES
61These functions return the value of
62.Fa x
63times 2 raised to the power
64.Fa exp .
65.Sh SEE ALSO
66.Xr frexp 3 ,
67.Xr math 3 ,
68.Xr modf 3
69.Sh STANDARDS
70The
71.Fn ldexp
72and
73.Fn ldexpf
74functions conform to
75.St -isoC-99 .
76