44 lines
999 B
C
44 lines
999 B
C
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/* @(#)w_log10.c 5.1 93/09/24 */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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#include <sys/cdefs.h>
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#if defined(LIBM_SCCS) && !defined(lint)
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__RCSID("$NetBSD: w_log2.c,v 1.1 2005/07/21 16:58:39 christos Exp $");
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#endif
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/*
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* wrapper log2(X)
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*/
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#include "math.h"
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#include "math_private.h"
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double
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log2(double x) /* wrapper log10 */
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{
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#ifdef _IEEE_LIBM
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return __ieee754_log2(x);
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#else
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double z;
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z = __ieee754_log2(x);
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if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
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if(x<=0.0) {
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if(x==0.0)
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return __kernel_standard(x,x,48); /* log2(0) */
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else
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return __kernel_standard(x,x,49); /* log2(x<0) */
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} else
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return z;
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#endif
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}
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