1994-05-27 05:00:24 +00:00
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.\" Copyright (c) 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" This code is derived from software contributed to Berkeley by
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.\" the American National Standards Committee X3, on Information
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.\" Processing Systems.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)frexp.3 8.1 (Berkeley) 6/4/93
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1999-08-28 00:22:10 +00:00
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.\" $FreeBSD$
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1994-05-27 05:00:24 +00:00
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.\"
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2005-03-07 05:00:54 +00:00
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.Dd March 4, 2005
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1994-05-27 05:00:24 +00:00
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.Dt FREXP 3
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.Os
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.Sh NAME
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2005-03-07 05:00:54 +00:00
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.Nm frexp ,
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.Nm frexpf ,
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.Nm frexpl
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1994-05-27 05:00:24 +00:00
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.Nd convert floating-point number to fractional and integral components
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2000-04-21 09:42:15 +00:00
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.Sh LIBRARY
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2005-01-23 16:49:40 +00:00
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.Lb libm
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1994-05-27 05:00:24 +00:00
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.Sh SYNOPSIS
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2001-10-01 16:09:29 +00:00
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.In math.h
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1994-05-27 05:00:24 +00:00
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.Ft double
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.Fn frexp "double value" "int *exp"
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.Ft float
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.Fn frexpf "float value" "int *exp"
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.Ft long double
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.Fn frexpl "long double value" "int *exp"
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1994-05-27 05:00:24 +00:00
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.Sh DESCRIPTION
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The
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2005-03-07 05:00:54 +00:00
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.Fn frexp ,
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.Fn frexpf
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2005-03-07 05:00:54 +00:00
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and
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.Fn frexpl
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2005-01-23 16:49:40 +00:00
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functions break a floating-point number into a normalized
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1994-05-27 05:00:24 +00:00
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fraction and an integral power of 2.
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They store the integer in the
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2002-12-18 13:33:04 +00:00
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.Vt int
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1994-05-27 05:00:24 +00:00
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object pointed to by
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.Fa exp .
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.Sh RETURN VALUES
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2005-01-23 16:49:40 +00:00
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These functions return the value
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.Va x ,
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1994-05-27 05:00:24 +00:00
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such that
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2002-12-18 13:33:04 +00:00
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.Va x
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is a
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.Vt double
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1994-05-27 05:00:24 +00:00
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with magnitude in the interval
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2001-05-23 12:37:50 +00:00
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.Bo 1/2 , 1 Pc
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1994-05-27 05:00:24 +00:00
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or zero, and
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.Fa value
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equals
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.Va x
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1994-05-27 05:00:24 +00:00
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times 2 raised to the power
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.Fa *exp .
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If
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.Fa value
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2000-10-30 13:23:19 +00:00
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is zero, both parts of the result are zero.
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1994-05-27 05:00:24 +00:00
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.Sh SEE ALSO
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.Xr ldexp 3 ,
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1997-01-20 23:23:22 +00:00
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.Xr math 3 ,
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.Xr modf 3
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1994-05-27 05:00:24 +00:00
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.Sh STANDARDS
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The
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.Fn frexp ,
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.Fn frexpf ,
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and
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.Fn frexpl
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2005-01-23 16:49:40 +00:00
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functions conform to
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.St -isoC-99 .
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