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/* s_asinhf.c -- float version of s_asinh.c. |
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* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
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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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#include "math.h" |
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#include "math_private.h" |
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static const float |
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one = 1.0000000000e+00, /* 0x3F800000 */ |
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ln2 = 6.9314718246e-01, /* 0x3f317218 */ |
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huge= 1.0000000000e+30; |
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float |
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asinhf(float x) |
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{ |
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float t,w; |
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int32_t hx,ix; |
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GET_FLOAT_WORD(hx,x); |
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ix = hx&0x7fffffff; |
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if(ix>=0x7f800000) return x+x; /* x is inf or NaN */ |
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if(ix< 0x31800000) { /* |x|<2**-28 */ |
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if(huge+x>one) return x; /* return x inexact except 0 */ |
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} |
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if(ix>0x4d800000) { /* |x| > 2**28 */ |
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w = logf(fabsf(x))+ln2; |
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} else if (ix>0x40000000) { /* 2**28 > |x| > 2.0 */ |
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t = fabsf(x); |
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w = logf((float)2.0*t+one/(sqrtf(x*x+one)+t)); |
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} else { /* 2.0 > |x| > 2**-28 */ |
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t = x*x; |
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w =log1pf(fabsf(x)+t/(one+sqrtf(one+t))); |
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} |
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if(hx>0) return w; else return -w; |
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} |