44 lines
977 B
C
44 lines
977 B
C
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/* @(#)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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#ifndef lint
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static char rcsid[] = "$Id: w_log.c,v 1.4 1994/08/10 20:35:09 jtc 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 "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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double log(double x) /* wrapper log */
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#else
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double log(x) /* wrapper log */
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double x;
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#endif
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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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