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.\" @(#)frexp.3 8.1 (Berkeley) 6/4/93 37.\" $FreeBSD: src/lib/libc/gen/frexp.3,v 1.4.2.5 2003/03/13 18:05:37 trhodes Exp $ 38.\" $DragonFly: src/lib/libc/gen/frexp.3,v 1.2 2003/06/17 04:26:42 dillon Exp $ 39.\" 40.Dd June 4, 1993 41.Dt FREXP 3 42.Os 43.Sh NAME 44.Nm frexp 45.Nd convert floating-point number to fractional and integral components 46.Sh LIBRARY 47.Lb libc 48.Sh SYNOPSIS 49.In math.h 50.Ft double 51.Fn frexp "double value" "int *exp" 52.Sh DESCRIPTION 53The 54.Fn frexp 55function breaks a floating-point number into a normalized 56fraction and an integral power of 2. 57It stores the integer in the 58.Vt int 59object pointed to by 60.Fa exp . 61.Sh RETURN VALUES 62The 63.Fn frexp 64function returns the value 65.Va x , 66such that 67.Va x 68is a 69.Vt double 70with magnitude in the interval 71.Bo 1/2 , 1 Pc 72or zero, and 73.Fa value 74equals 75.Va x 76times 2 raised to the power 77.Fa *exp . 78If 79.Fa value 80is zero, both parts of the result are zero. 81.Sh SEE ALSO 82.Xr ldexp 3 , 83.Xr math 3 , 84.Xr modf 3 85.Sh STANDARDS 86The 87.Fn frexp 88function conforms to 89.St -isoC . 90