Libc-262.3.2.tar.gz

[apple/libc.git] / gen / frexp.3

.\" Copyright (c) 1991, 1993
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.\"     @(#)frexp.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/frexp.3,v 1.9 2001/10/01 16:08:50 ru 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
.Em int
object pointed to by
.Fa exp .
.Sh RETURN VALUES
The
.Fn frexp
function returns the value
.Em x ,
such that
.Em x
is a
.Em double
with magnitude in the interval
.Bo 1/2 , 1 Pc
or zero, and
.Fa value
equals
.Em 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 .