.\" Copyright (c) 1991, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
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.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
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.\" @(#)frexp.3 8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/frexp.3,v 1.4.2.5 2003/03/13 18:05:37 trhodes Exp $
.\" $DragonFly: src/lib/libc/gen/frexp.3,v 1.3 2006/02/28 02:25:10 swildner Exp $
.\"
.Dd June 4, 1993
.Dt FREXP 3
.Os
.Sh NAME
.Nm frexp
.Nd convert floating-point number to fractional and integral components
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn frexp "double value" "int *exp"
.Sh DESCRIPTION
The
.Fn frexp
function breaks a floating-point number into a normalized
fraction and an integral power of 2.
It stores the integer in the
.Vt int
object pointed to by
.Fa exp .
.Sh RETURN VALUES
The
.Fn frexp
function returns the value
.Va x ,
such that
.Va x
is a
.Vt double
with magnitude in the interval
.Bo \(12 , 1 Pc
or zero, and
.Fa value
equals
.Va x
times 2 raised to the power
.Fa *exp .
If
.Fa value
is zero, both parts of the result are zero.
.Sh SEE ALSO
.Xr ldexp 3 ,
.Xr math 3 ,
.Xr modf 3
.Sh STANDARDS
The
.Fn frexp
function conforms to
.St -isoC .