1.\" $OpenBSD: frexp.3,v 1.14 2022/09/11 06:38:10 jmc 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.Dd $Mdocdate: September 11 2022 $ 35.Dt FREXP 3 36.Os 37.Sh NAME 38.Nm frexp , 39.Nm frexpf , 40.Nm frexpl 41.Nd convert floating-point number to fractional and integral components 42.Sh SYNOPSIS 43.In math.h 44.Ft double 45.Fn frexp "double value" "int *exp" 46.Ft float 47.Fn frexpf "float value" "int *exp" 48.Ft long double 49.Fn frexpl "long double 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.Vt int 57object pointed to by 58.Fa exp . 59The 60.Fn frexpf 61function is a single precision version of 62.Fn frexp . 63The 64.Fn frexpl 65function is an extended precision version of 66.Fn frexp . 67.Sh RETURN VALUES 68The 69.Fn frexp , 70.Fn frexpf 71and 72.Fn frexpl 73functions return the value 74.Li x , 75such that 76.Li x 77is a 78.Vt double 79with magnitude in the interval [1/2,\ 1) or zero, and 80.Fa value 81equals 82.Li x 83times 2 raised to the power 84.Fa *exp . 85If 86.Fa value 87is zero, both parts of the result are zero. 88.Sh SEE ALSO 89.Xr ldexp 3 , 90.Xr modf 3 91.Sh STANDARDS 92The 93.Fn frexp 94function conforms to 95.St -ansiC . 96