55 lines
1.4 KiB
C
55 lines
1.4 KiB
C
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/* $NetBSD: frexp.c,v 1.1 1995/02/10 17:50:22 cgd Exp $ */
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/* $FreeBSD$ */
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/*
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* Copyright (c) 1994, 1995 Carnegie-Mellon University.
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* All rights reserved.
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*
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* Author: Chris G. Demetriou
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*
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* Permission to use, copy, modify and distribute this software and
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* its documentation is hereby granted, provided that both the copyright
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* notice and this permission notice appear in all copies of the
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* software, derivative works or modified versions, and any portions
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* thereof, and that both notices appear in supporting documentation.
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*
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* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
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* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
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* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
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*
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* Carnegie Mellon requests users of this software to return to
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*
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* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
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* School of Computer Science
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* Carnegie Mellon University
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* Pittsburgh PA 15213-3890
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*
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* any improvements or extensions that they make and grant Carnegie the
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* rights to redistribute these changes.
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*/
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#include <sys/types.h>
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#include <machine/ieee.h>
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#include <math.h>
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double
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frexp(value, eptr)
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double value;
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int *eptr;
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{
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union doub {
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double v;
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struct ieee_double s;
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} u;
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if (value) {
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u.v = value;
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*eptr = u.s.dbl_exp - (DBL_EXP_BIAS - 1);
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u.s.dbl_exp = DBL_EXP_BIAS - 1;
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return(u.v);
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} else {
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*eptr = 0;
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return((double)0);
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}
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}
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