1.\" $NetBSD: frexp.3,v 1.2 2010/04/29 08:35:03 joerg Exp $ 2.\" 3.\" Copyright (c) 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" the American National Standards Committee X3, on Information 8.\" Processing Systems. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)frexp.3 8.1 (Berkeley) 6/4/93 35.\" 36.Dd March 21, 2006 37.Dt FREXP 3 38.Os 39.Sh NAME 40.Nm frexp 41.Nd convert floating-point number to fractional and integral components 42.Sh LIBRARY 43.Lb libm 44.Sh SYNOPSIS 45.In math.h 46.Ft double 47.Fn frexp "double value" "int *exp" 48.Ft float 49.Fn frexpf "float value" "int *exp" 50.Sh DESCRIPTION 51The 52.Fn frexp 53function breaks a floating-point number into a normalized 54fraction and an integral power of 2. 55It stores the integer in the 56.Em int 57object pointed to by 58.Fa exp . 59.Sh RETURN VALUES 60The 61.Fn frexp 62function returns the value 63.Em x , 64such that 65.Em x 66is a 67.Em double 68with magnitude in the interval [1/2, 1) or zero, and 69.Fa value 70equals 71.Em x 72times 2 raised to the power 73.Fa *exp . 74If 75.Fa value 76is zero, both parts of the result are zero. 77.Sh SEE ALSO 78.Xr ldexp 3 , 79.Xr math 3 , 80.Xr modf 3 81.Sh STANDARDS 82The 83.Fn frexp 84function conforms to 85.St -ansiC . 86