This work is based in part on code from NetBSD libm, libc and kernel. The library is partly public domain and partly BSD-style licensed.
45 lines
1,021 B
C
45 lines
1,021 B
C
/* @(#)w_log.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_log.c,v 1.10 2007/08/20 16:01:40 drochner Exp $");
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#endif
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/*
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* wrapper log(x)
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*/
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#include "namespace.h"
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#include "math.h"
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#include "math_private.h"
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#ifdef __weak_alias
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__weak_alias(log, _log)
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#endif
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double
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log(double x) /* wrapper log */
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{
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#ifdef _IEEE_LIBM
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return __ieee754_log(x);
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#else
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double z;
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z = __ieee754_log(x);
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if(_LIB_VERSION == _IEEE_ || isnan(x) || x > 0.0) return z;
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if(x==0.0)
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return __kernel_standard(x,x,16); /* log(0) */
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else
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return __kernel_standard(x,x,17); /* log(x<0) */
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#endif
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}
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