xref: /netbsd/lib/libm/man/frexp.3 (revision 5175c414)
1*5175c414Swiz.\"	$NetBSD: frexp.3,v 1.4 2015/09/10 12:30:08 wiz Exp $
251086becSdrochner.\"
351086becSdrochner.\" Copyright (c) 1991, 1993
451086becSdrochner.\"	The Regents of the University of California.  All rights reserved.
551086becSdrochner.\"
651086becSdrochner.\" This code is derived from software contributed to Berkeley by
751086becSdrochner.\" the American National Standards Committee X3, on Information
851086becSdrochner.\" Processing Systems.
951086becSdrochner.\"
1051086becSdrochner.\" Redistribution and use in source and binary forms, with or without
1151086becSdrochner.\" modification, are permitted provided that the following conditions
1251086becSdrochner.\" are met:
1351086becSdrochner.\" 1. Redistributions of source code must retain the above copyright
1451086becSdrochner.\"    notice, this list of conditions and the following disclaimer.
1551086becSdrochner.\" 2. Redistributions in binary form must reproduce the above copyright
1651086becSdrochner.\"    notice, this list of conditions and the following disclaimer in the
1751086becSdrochner.\"    documentation and/or other materials provided with the distribution.
1851086becSdrochner.\" 3. Neither the name of the University nor the names of its contributors
1951086becSdrochner.\"    may be used to endorse or promote products derived from this software
2051086becSdrochner.\"    without specific prior written permission.
2151086becSdrochner.\"
2251086becSdrochner.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2351086becSdrochner.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2451086becSdrochner.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2551086becSdrochner.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2651086becSdrochner.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2751086becSdrochner.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2851086becSdrochner.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2951086becSdrochner.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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3151086becSdrochner.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3251086becSdrochner.\" SUCH DAMAGE.
3351086becSdrochner.\"
3451086becSdrochner.\"     @(#)frexp.3	8.1 (Berkeley) 6/4/93
3551086becSdrochner.\"
36*5175c414Swiz.Dd September 10, 2015
3751086becSdrochner.Dt FREXP 3
3851086becSdrochner.Os
3951086becSdrochner.Sh NAME
4051086becSdrochner.Nm frexp
4151086becSdrochner.Nd convert floating-point number to fractional and integral components
4251086becSdrochner.Sh LIBRARY
4351086becSdrochner.Lb libm
4451086becSdrochner.Sh SYNOPSIS
4551086becSdrochner.In math.h
4651086becSdrochner.Ft double
4751086becSdrochner.Fn frexp "double value" "int *exp"
4851086becSdrochner.Ft float
4951086becSdrochner.Fn frexpf "float value" "int *exp"
50d6d04bbfShe.Ft long double
51d6d04bbfShe.Fn frexpl "long double value" "int *exp"
5251086becSdrochner.Sh DESCRIPTION
5351086becSdrochnerThe
5451086becSdrochner.Fn frexp
5551086becSdrochnerfunction breaks a floating-point number into a normalized
5651086becSdrochnerfraction and an integral power of 2.
5751086becSdrochnerIt stores the integer in the
5851086becSdrochner.Em int
5951086becSdrochnerobject pointed to by
6051086becSdrochner.Fa exp .
6151086becSdrochner.Sh RETURN VALUES
6251086becSdrochnerThe
6351086becSdrochner.Fn frexp
6451086becSdrochnerfunction returns the value
6551086becSdrochner.Em x ,
6651086becSdrochnersuch that
6751086becSdrochner.Em x
6851086becSdrochneris a
6951086becSdrochner.Em double
7079b996cbSjoergwith magnitude in the interval [1/2, 1) or zero, and
7151086becSdrochner.Fa value
7251086becSdrochnerequals
7351086becSdrochner.Em x
7451086becSdrochnertimes 2 raised to the power
7551086becSdrochner.Fa *exp .
7651086becSdrochnerIf
7751086becSdrochner.Fa value
7851086becSdrochneris zero, both parts of the result are zero.
7951086becSdrochner.Sh SEE ALSO
8051086becSdrochner.Xr ldexp 3 ,
8151086becSdrochner.Xr math 3 ,
8251086becSdrochner.Xr modf 3
8351086becSdrochner.Sh STANDARDS
8451086becSdrochnerThe
8551086becSdrochner.Fn frexp
8651086becSdrochnerfunction conforms to
8751086becSdrochner.St -ansiC .
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