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/* @(#)w_exp.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_exp.c,v 1.2 1995/05/30 05:50:58 rgrimes Exp $";
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#endif
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/*
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 * wrapper exp(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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static const double
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#else
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static double
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#endif
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o_threshold=  7.09782712893383973096e+02,  /* 0x40862E42, 0xFEFA39EF */
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u_threshold= -7.45133219101941108420e+02;  /* 0xc0874910, 0xD52D3051 */
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#ifdef __STDC__
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        double exp(double x)            /* wrapper exp */
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#else
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        double exp(x)                   /* wrapper exp */
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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_exp(x);
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#else
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        double z;
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        z = __ieee754_exp(x);
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        if(_LIB_VERSION == _IEEE_) return z;
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        if(finite(x)) {
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            if(x>o_threshold)
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                return __kernel_standard(x,x,6); /* exp overflow */
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            else if(x<u_threshold)
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                return __kernel_standard(x,x,7); /* exp underflow */
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        }
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        return z;
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#endif
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}