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.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)frexp.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: src/lib/libc/gen/frexp.3,v 1.13 2007/01/09 00:27:53 imp Exp $ 34.\" $DragonFly: src/lib/libc/gen/frexp.3,v 1.3 2006/02/28 02:25:10 swildner Exp $ 35.\" 36.Dd March 4, 2005 37.Dt FREXP 3 38.Os 39.Sh NAME 40.Nm frexp , 41.Nm frexpf , 42.Nm frexpl 43.Nd convert floating-point number to fractional and integral components 44.Sh LIBRARY 45.Lb libm 46.Sh SYNOPSIS 47.In math.h 48.Ft double 49.Fn frexp "double value" "int *exp" 50.Ft float 51.Fn frexpf "float value" "int *exp" 52.Ft long double 53.Fn frexpl "long double value" "int *exp" 54.Sh DESCRIPTION 55The 56.Fn frexp , 57.Fn frexpf 58and 59.Fn frexpl 60functions break a floating-point number into a normalized 61fraction and an integral power of 2. 62They store the integer in the 63.Vt int 64object pointed to by 65.Fa exp . 66.Sh RETURN VALUES 67These functions return the value 68.Va x , 69such that 70.Va x 71is a 72.Vt double 73with magnitude in the interval 74.Eo [ \(12 , 1 Ec ) 75or zero, and 76.Fa value 77equals 78.Va x 79times 2 raised to the power 80.Fa *exp . 81If 82.Fa value 83is zero, both parts of the result are zero. 84.Sh SEE ALSO 85.Xr ldexp 3 , 86.Xr math 3 , 87.Xr modf 3 88.Sh STANDARDS 89The 90.Fn frexp , 91.Fn frexpf , 92and 93.Fn frexpl 94functions conform to 95.St -isoC-99 . 96