49 lines
947 B
C
49 lines
947 B
C
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/* sf_log2.c -- float version of s_log2.c.
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* Modification of sf_exp10.c by Yaakov Selkowitz 2009.
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*/
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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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/*
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* wrapper log2f(x)
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*/
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#include "fdlibm.h"
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#include <errno.h>
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#include <math.h>
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#undef log2
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#undef log2f
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#ifdef __STDC__
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float log2f(float x) /* wrapper log2f */
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#else
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float log2f(x) /* wrapper log2f */
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float x;
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#endif
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{
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return (logf(x) / (float) M_LOG2_E);
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}
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#ifdef _DOUBLE_IS_32BITS
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#ifdef __STDC__
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double log2(double x)
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#else
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double log2(x)
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double x;
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#endif
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{
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return (double) log2f((float) x);
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}
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#endif /* defined(_DOUBLE_IS_32BITS) */
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