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📄 e_acos.c(3.38 KB)
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📄 e_acosh.c(1.63 KB)
📄 e_acoshf.c(1.27 KB)
📄 e_acoshl.c(2.19 KB)
📄 e_acosl.c(2.16 KB)
📄 e_asin.c(3.55 KB)
📄 e_asinf.c(1.58 KB)
📄 e_asinl.c(1.85 KB)
📄 e_atan2.c(3.74 KB)
📄 e_atan2f.c(2.63 KB)
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📄 e_atanh.c(1.64 KB)
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📄 e_coshl.c(4 KB)
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📄 e_expf.c(2.7 KB)
📄 e_fmod.c(3.34 KB)
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📄 e_fmodl.c(3.77 KB)
📄 e_gamma.c(725 B)
📄 e_gamma_r.c(801 B)
📄 e_gammaf.c(814 B)
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📄 e_hypot.c(3.22 KB)
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📄 e_j0.c(14.39 KB)
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📄 e_j1.c(14.12 KB)
📄 e_j1f.c(9.98 KB)
📄 e_jn.c(7.08 KB)
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📄 e_lgamma.c(819 B)
📄 e_lgamma_r.c(10.7 KB)
📄 e_lgammaf.c(820 B)
📄 e_lgammaf_r.c(5.82 KB)
📄 e_lgammal.c(599 B)
📄 e_log.c(4.42 KB)
📄 e_log10.c(2.5 KB)
📄 e_log10f.c(1.93 KB)
📄 e_log2.c(3.64 KB)
📄 e_log2f.c(2.37 KB)
📄 e_logf.c(2.36 KB)
📄 e_pow.c(9.84 KB)
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📄 e_rem_pio2.c(4.7 KB)
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📄 e_remainder.c(1.75 KB)
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📄 e_remainderl.c(1.55 KB)
📄 e_scalb.c(1.07 KB)
📄 e_scalbf.c(1.06 KB)
📄 e_sinh.c(2.03 KB)
📄 e_sinhf.c(1.43 KB)
📄 e_sinhl.c(4.12 KB)
📄 e_sqrt.c(14.12 KB)
📄 e_sqrtf.c(1.91 KB)
📄 e_sqrtl.c(4.28 KB)
📄 fenv-softfloat.h(4.96 KB)
📄 imprecise.c(2.08 KB)
📄 k_cos.c(2.75 KB)
📄 k_cosf.c(1.23 KB)
📄 k_exp.c(3.55 KB)
📄 k_expf.c(2.67 KB)
📄 k_log.h(3.34 KB)
📄 k_logf.h(992 B)
📄 k_rem_pio2.c(15.51 KB)
📄 k_sin.c(2.27 KB)
📄 k_sincos.h(1.7 KB)
📄 k_sincosf.h(1.38 KB)
📄 k_sincosl.h(4.82 KB)
📄 k_sinf.c(1.21 KB)
📄 k_tan.c(3.93 KB)
📄 k_tanf.c(1.97 KB)
📄 math.h(13.92 KB)
📄 math_private.h(24.72 KB)
📄 s_asinh.c(1.64 KB)
📄 s_asinhf.c(1.32 KB)
📄 s_asinhl.c(2.41 KB)
📄 s_atan.c(4.08 KB)
📄 s_atanf.c(2.42 KB)
📄 s_atanl.c(2.32 KB)
📄 s_carg.c(1.55 KB)
📄 s_cargf.c(1.55 KB)
📄 s_cargl.c(1.57 KB)
📄 s_cbrt.c(4.03 KB)
📄 s_cbrtf.c(1.85 KB)
📄 s_cbrtl.c(3.34 KB)
📄 s_ccosh.c(5.01 KB)
📄 s_ccoshf.c(3.08 KB)
📄 s_ceil.c(1.73 KB)
📄 s_ceilf.c(1.24 KB)
📄 s_ceill.c(2.38 KB)
📄 s_cexp.c(2.88 KB)
📄 s_cexpf.c(2.85 KB)
📄 s_cimag.c(1.53 KB)
📄 s_cimagf.c(1.53 KB)
📄 s_cimagl.c(1.55 KB)
📄 s_clog.c(5.06 KB)
📄 s_clogf.c(5.01 KB)
📄 s_clogl.c(5.49 KB)
📄 s_conj.c(1.51 KB)
📄 s_conjf.c(1.52 KB)
📄 s_conjl.c(1.53 KB)
📄 s_copysign.c(808 B)
📄 s_copysignf.c(905 B)
📄 s_copysignl.c(1.57 KB)
📄 s_cos.c(2.19 KB)
📄 s_cosf.c(2.2 KB)
📄 s_cosl.c(2.55 KB)
📄 s_cpow.c(1.8 KB)
📄 s_cpowf.c(1.79 KB)
📄 s_cpowl.c(1.83 KB)
📄 s_cproj.c(1.74 KB)
📄 s_cprojf.c(1.66 KB)
📄 s_cprojl.c(1.68 KB)
📄 s_creal.c(1.45 KB)
📄 s_crealf.c(1.45 KB)
📄 s_creall.c(1.46 KB)
📄 s_csinh.c(5.01 KB)
📄 s_csinhf.c(3.06 KB)
📄 s_csqrt.c(3.29 KB)
📄 s_csqrtf.c(2.65 KB)
📄 s_csqrtl.c(3.78 KB)
📄 s_ctanh.c(4.32 KB)
📄 s_ctanhf.c(2.45 KB)
📄 s_erf.c(11 KB)
📄 s_erff.c(5.11 KB)
📄 s_exp2.c(14.03 KB)
📄 s_exp2f.c(4.14 KB)
📄 s_expm1.c(7.18 KB)
📄 s_expm1f.c(3.41 KB)
📄 s_fabs.c(677 B)
📄 s_fabsf.c(765 B)
📄 s_fabsl.c(1.68 KB)
📄 s_fdim.c(1.7 KB)
📄 s_finite.c(700 B)
📄 s_finitef.c(796 B)
📄 s_floor.c(1.74 KB)
📄 s_floorf.c(1.41 KB)
📄 s_floorl.c(2.38 KB)
📄 s_fma.c(7.92 KB)
📄 s_fmaf.c(2.57 KB)
📄 s_fmal.c(7.38 KB)
📄 s_fmax.c(2.01 KB)
📄 s_fmaxf.c(1.88 KB)
📄 s_fmaxl.c(1.98 KB)
📄 s_fmin.c(2.01 KB)
📄 s_fminf.c(1.88 KB)
📄 s_fminl.c(1.98 KB)
📄 s_frexp.c(1.31 KB)
📄 s_frexpf.c(1.02 KB)
📄 s_frexpl.c(2 KB)
📄 s_ilogb.c(1.14 KB)
📄 s_ilogbf.c(976 B)
📄 s_ilogbl.c(1.21 KB)
📄 s_isfinite.c(1.72 KB)
📄 s_isnan.c(2.1 KB)
📄 s_isnormal.c(1.78 KB)
📄 s_llrint.c(156 B)
📄 s_llrintf.c(157 B)
📄 s_llrintl.c(163 B)
📄 s_llround.c(215 B)
📄 s_llroundf.c(216 B)
📄 s_llroundl.c(222 B)
📄 s_log1p.c(5.6 KB)
📄 s_log1pf.c(3.14 KB)
📄 s_logb.c(1.13 KB)
📄 s_logbf.c(1023 B)
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📄 s_lrint.c(2.1 KB)
📄 s_lrintf.c(151 B)
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📄 s_lround.c(2.45 KB)
📄 s_lroundf.c(208 B)
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📄 s_modf.c(1.88 KB)
📄 s_modff.c(1.39 KB)
📄 s_modfl.c(3.41 KB)
📄 s_nan.c(3.32 KB)
📄 s_nearbyint.c(2.29 KB)
📄 s_nextafter.c(2.03 KB)
📄 s_nextafterf.c(1.61 KB)
📄 s_nextafterl.c(2.02 KB)
📄 s_nexttoward.c(1.75 KB)
📄 s_nexttowardf.c(1.42 KB)
📄 s_remquo.c(3.86 KB)
📄 s_remquof.c(3.02 KB)
📄 s_remquol.c(4.42 KB)
📄 s_rint.c(2.33 KB)
📄 s_rintf.c(1.22 KB)
📄 s_rintl.c(2.77 KB)
📄 s_round.c(1.83 KB)
📄 s_roundf.c(1.74 KB)
📄 s_roundl.c(1.84 KB)
📄 s_scalbln.c(1.82 KB)
📄 s_scalbn.c(1.9 KB)
📄 s_scalbnf.c(1.67 KB)
📄 s_scalbnl.c(1.9 KB)
📄 s_signbit.c(1.7 KB)
📄 s_signgam.c(61 B)
📄 s_significand.c(727 B)
📄 s_significandf.c(691 B)
📄 s_sin.c(2.18 KB)
📄 s_sincos.c(1.6 KB)
📄 s_sincosf.c(2.57 KB)
📄 s_sincosl.c(2.67 KB)
📄 s_sinf.c(2.18 KB)
📄 s_sinl.c(2.49 KB)
📄 s_tan.c(2.02 KB)
📄 s_tanf.c(1.97 KB)
📄 s_tanh.c(2.02 KB)
📄 s_tanhf.c(1.39 KB)
📄 s_tanhl.c(5.09 KB)
📄 s_tanl.c(2.6 KB)
📄 s_tgammaf.c(1.75 KB)
📄 s_trunc.c(1.5 KB)
📄 s_truncf.c(1.21 KB)
📄 s_truncl.c(1.61 KB)
📄 w_cabs.c(365 B)
📄 w_cabsf.c(350 B)
📄 w_cabsl.c(357 B)
📄 w_drem.c(211 B)
📄 w_dremf.c(254 B)

Editing: s_erf.c

/* @(#)s_erf.c 5.1 93/09/24 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice
 * is preserved.
 * ====================================================
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

/* double erf(double x)
 * double erfc(double x)
 *			     x
 *		      2      |\
 *     erf(x)  =  ---------  | exp(-t*t)dt
 *	 	   sqrt(pi) \|
 *			     0
 *
 *     erfc(x) =  1-erf(x)
 *  Note that
 *		erf(-x) = -erf(x)
 *		erfc(-x) = 2 - erfc(x)
 *
 * Method:
 *	1. For |x| in [0, 0.84375]
 *	    erf(x)  = x + x*R(x^2)
 *          erfc(x) = 1 - erf(x)           if x in [-.84375,0.25]
 *                  = 0.5 + ((0.5-x)-x*R)  if x in [0.25,0.84375]
 *	   where R = P/Q where P is an odd poly of degree 8 and
 *	   Q is an odd poly of degree 10.
 *						 -57.90
 *			| R - (erf(x)-x)/x | <= 2
 *
 *
 *	   Remark. The formula is derived by noting
 *          erf(x) = (2/sqrt(pi))*(x - x^3/3 + x^5/10 - x^7/42 + ....)
 *	   and that
 *          2/sqrt(pi) = 1.128379167095512573896158903121545171688
 *	   is close to one. The interval is chosen because the fix
 *	   point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is
 *	   near 0.6174), and by some experiment, 0.84375 is chosen to
 * 	   guarantee the error is less than one ulp for erf.
 *
 *      2. For |x| in [0.84375,1.25], let s = |x| - 1, and
 *         c = 0.84506291151 rounded to single (24 bits)
 *         	erf(x)  = sign(x) * (c  + P1(s)/Q1(s))
 *         	erfc(x) = (1-c)  - P1(s)/Q1(s) if x > 0
 *			  1+(c+P1(s)/Q1(s))    if x < 0
 *         	|P1/Q1 - (erf(|x|)-c)| <= 2**-59.06
 *	   Remark: here we use the taylor series expansion at x=1.
 *		erf(1+s) = erf(1) + s*Poly(s)
 *			 = 0.845.. + P1(s)/Q1(s)
 *	   That is, we use rational approximation to approximate
 *			erf(1+s) - (c = (single)0.84506291151)
 *	   Note that |P1/Q1|< 0.078 for x in [0.84375,1.25]
 *	   where
 *		P1(s) = degree 6 poly in s
 *		Q1(s) = degree 6 poly in s
 *
 *      3. For x in [1.25,1/0.35(~2.857143)],
 *         	erfc(x) = (1/x)*exp(-x*x-0.5625+R1/S1)
 *         	erf(x)  = 1 - erfc(x)
 *	   where
 *		R1(z) = degree 7 poly in z, (z=1/x^2)
 *		S1(z) = degree 8 poly in z
 *
 *      4. For x in [1/0.35,28]
 *         	erfc(x) = (1/x)*exp(-x*x-0.5625+R2/S2) if x > 0
 *			= 2.0 - (1/x)*exp(-x*x-0.5625+R2/S2) if -6<x<0
 *			= 2.0 - tiny		(if x <= -6)
 *         	erf(x)  = sign(x)*(1.0 - erfc(x)) if x < 6, else
 *         	erf(x)  = sign(x)*(1.0 - tiny)
 *	   where
 *		R2(z) = degree 6 poly in z, (z=1/x^2)
 *		S2(z) = degree 7 poly in z
 *
 *      Note1:
 *	   To compute exp(-x*x-0.5625+R/S), let s be a single
 *	   precision number and s := x; then
 *		-x*x = -s*s + (s-x)*(s+x)
 *	        exp(-x*x-0.5626+R/S) =
 *			exp(-s*s-0.5625)*exp((s-x)*(s+x)+R/S);
 *      Note2:
 *	   Here 4 and 5 make use of the asymptotic series
 *			  exp(-x*x)
 *		erfc(x) ~ ---------- * ( 1 + Poly(1/x^2) )
 *			  x*sqrt(pi)
 *	   We use rational approximation to approximate
 *      	g(s)=f(1/x^2) = log(erfc(x)*x) - x*x + 0.5625
 *	   Here is the error bound for R1/S1 and R2/S2
 *      	|R1/S1 - f(x)|  < 2**(-62.57)
 *      	|R2/S2 - f(x)|  < 2**(-61.52)
 *
 *      5. For inf > x >= 28
 *         	erf(x)  = sign(x) *(1 - tiny)  (raise inexact)
 *         	erfc(x) = tiny*tiny (raise underflow) if x > 0
 *			= 2 - tiny if x<0
 *
 *      7. Special case:
 *         	erf(0)  = 0, erf(inf)  = 1, erf(-inf) = -1,
 *         	erfc(0) = 1, erfc(inf) = 0, erfc(-inf) = 2,
 *	   	erfc/erf(NaN) is NaN
 */

#include <float.h>
#include "math.h"
#include "math_private.h"

/* XXX Prevent compilers from erroneously constant folding: */
static const volatile double tiny= 1e-300;

static const double
half= 0.5,
one = 1,
two = 2,
/* c = (float)0.84506291151 */
erx =  8.45062911510467529297e-01, /* 0x3FEB0AC1, 0x60000000 */
/*
 * In the domain [0, 2**-28], only the first term in the power series
 * expansion of erf(x) is used.  The magnitude of the first neglected
 * terms is less than 2**-84.
 */
efx =  1.28379167095512586316e-01, /* 0x3FC06EBA, 0x8214DB69 */
efx8=  1.02703333676410069053e+00, /* 0x3FF06EBA, 0x8214DB69 */
/*
 * Coefficients for approximation to erf on [0,0.84375]
 */
pp0  =  1.28379167095512558561e-01, /* 0x3FC06EBA, 0x8214DB68 */
pp1  = -3.25042107247001499370e-01, /* 0xBFD4CD7D, 0x691CB913 */
pp2  = -2.84817495755985104766e-02, /* 0xBF9D2A51, 0xDBD7194F */
pp3  = -5.77027029648944159157e-03, /* 0xBF77A291, 0x236668E4 */
pp4  = -2.37630166566501626084e-05, /* 0xBEF8EAD6, 0x120016AC */
qq1  =  3.97917223959155352819e-01, /* 0x3FD97779, 0xCDDADC09 */
qq2  =  6.50222499887672944485e-02, /* 0x3FB0A54C, 0x5536CEBA */
qq3  =  5.08130628187576562776e-03, /* 0x3F74D022, 0xC4D36B0F */
qq4  =  1.32494738004321644526e-04, /* 0x3F215DC9, 0x221C1A10 */
qq5  = -3.96022827877536812320e-06, /* 0xBED09C43, 0x42A26120 */
/*
 * Coefficients for approximation to erf in [0.84375,1.25]
 */
pa0  = -2.36211856075265944077e-03, /* 0xBF6359B8, 0xBEF77538 */
pa1  =  4.14856118683748331666e-01, /* 0x3FDA8D00, 0xAD92B34D */
pa2  = -3.72207876035701323847e-01, /* 0xBFD7D240, 0xFBB8C3F1 */
pa3  =  3.18346619901161753674e-01, /* 0x3FD45FCA, 0x805120E4 */
pa4  = -1.10894694282396677476e-01, /* 0xBFBC6398, 0x3D3E28EC */
pa5  =  3.54783043256182359371e-02, /* 0x3FA22A36, 0x599795EB */
pa6  = -2.16637559486879084300e-03, /* 0xBF61BF38, 0x0A96073F */
qa1  =  1.06420880400844228286e-01, /* 0x3FBB3E66, 0x18EEE323 */
qa2  =  5.40397917702171048937e-01, /* 0x3FE14AF0, 0x92EB6F33 */
qa3  =  7.18286544141962662868e-02, /* 0x3FB2635C, 0xD99FE9A7 */
qa4  =  1.26171219808761642112e-01, /* 0x3FC02660, 0xE763351F */
qa5  =  1.36370839120290507362e-02, /* 0x3F8BEDC2, 0x6B51DD1C */
qa6  =  1.19844998467991074170e-02, /* 0x3F888B54, 0x5735151D */
/*
 * Coefficients for approximation to erfc in [1.25,1/0.35]
 */
ra0  = -9.86494403484714822705e-03, /* 0xBF843412, 0x600D6435 */
ra1  = -6.93858572707181764372e-01, /* 0xBFE63416, 0xE4BA7360 */
ra2  = -1.05586262253232909814e+01, /* 0xC0251E04, 0x41B0E726 */
ra3  = -6.23753324503260060396e+01, /* 0xC04F300A, 0xE4CBA38D */
ra4  = -1.62396669462573470355e+02, /* 0xC0644CB1, 0x84282266 */
ra5  = -1.84605092906711035994e+02, /* 0xC067135C, 0xEBCCABB2 */
ra6  = -8.12874355063065934246e+01, /* 0xC0545265, 0x57E4D2F2 */
ra7  = -9.81432934416914548592e+00, /* 0xC023A0EF, 0xC69AC25C */
sa1  =  1.96512716674392571292e+01, /* 0x4033A6B9, 0xBD707687 */
sa2  =  1.37657754143519042600e+02, /* 0x4061350C, 0x526AE721 */
sa3  =  4.34565877475229228821e+02, /* 0x407B290D, 0xD58A1A71 */
sa4  =  6.45387271733267880336e+02, /* 0x40842B19, 0x21EC2868 */
sa5  =  4.29008140027567833386e+02, /* 0x407AD021, 0x57700314 */
sa6  =  1.08635005541779435134e+02, /* 0x405B28A3, 0xEE48AE2C */
sa7  =  6.57024977031928170135e+00, /* 0x401A47EF, 0x8E484A93 */
sa8  = -6.04244152148580987438e-02, /* 0xBFAEEFF2, 0xEE749A62 */
/*
 * Coefficients for approximation to erfc in [1/.35,28]
 */
rb0  = -9.86494292470009928597e-03, /* 0xBF843412, 0x39E86F4A */
rb1  = -7.99283237680523006574e-01, /* 0xBFE993BA, 0x70C285DE */
rb2  = -1.77579549177547519889e+01, /* 0xC031C209, 0x555F995A */
rb3  = -1.60636384855821916062e+02, /* 0xC064145D, 0x43C5ED98 */
rb4  = -6.37566443368389627722e+02, /* 0xC083EC88, 0x1375F228 */
rb5  = -1.02509513161107724954e+03, /* 0xC0900461, 0x6A2E5992 */
rb6  = -4.83519191608651397019e+02, /* 0xC07E384E, 0x9BDC383F */
sb1  =  3.03380607434824582924e+01, /* 0x403E568B, 0x261D5190 */
sb2  =  3.25792512996573918826e+02, /* 0x40745CAE, 0x221B9F0A */
sb3  =  1.53672958608443695994e+03, /* 0x409802EB, 0x189D5118 */
sb4  =  3.19985821950859553908e+03, /* 0x40A8FFB7, 0x688C246A */
sb5  =  2.55305040643316442583e+03, /* 0x40A3F219, 0xCEDF3BE6 */
sb6  =  4.74528541206955367215e+02, /* 0x407DA874, 0xE79FE763 */
sb7  = -2.24409524465858183362e+01; /* 0xC03670E2, 0x42712D62 */

double
erf(double x)
{
	int32_t hx,ix,i;
	double R,S,P,Q,s,y,z,r;
	GET_HIGH_WORD(hx,x);
	ix = hx&0x7fffffff;
	if(ix>=0x7ff00000) {		/* erf(nan)=nan */
	    i = ((u_int32_t)hx>>31)<<1;
	    return (double)(1-i)+one/x;	/* erf(+-inf)=+-1 */
	}

if(ix < 0x3feb0000) {		/* |x|<0.84375 */
	    if(ix < 0x3e300000) { 	/* |x|<2**-28 */
	        if (ix < 0x00800000)
		    return (8*x+efx8*x)/8;	/* avoid spurious underflow */
		return x + efx*x;
	    }
	    z = x*x;
	    r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)));
	    s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
	    y = r/s;
	    return x + x*y;
	}
	if(ix < 0x3ff40000) {		/* 0.84375 <= |x| < 1.25 */
	    s = fabs(x)-one;
	    P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))));
	    Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
	    if(hx>=0) return erx + P/Q; else return -erx - P/Q;
	}
	if (ix >= 0x40180000) {		/* inf>|x|>=6 */
	    if(hx>=0) return one-tiny; else return tiny-one;
	}
	x = fabs(x);
 	s = one/(x*x);
	if(ix< 0x4006DB6E) {	/* |x| < 1/0.35 */
	    R=ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))));
	    S=one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+
		s*sa8)))))));
	} else {	/* |x| >= 1/0.35 */
	    R=rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))));
	    S=one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))));
	}
	z  = x;
	SET_LOW_WORD(z,0);
	r  =  __ieee754_exp(-z*z-0.5625)*__ieee754_exp((z-x)*(z+x)+R/S);
	if(hx>=0) return one-r/x; else return  r/x-one;
}

#if (LDBL_MANT_DIG == 53)
__weak_reference(erf, erfl);
#endif

double
erfc(double x)
{
	int32_t hx,ix;
	double R,S,P,Q,s,y,z,r;
	GET_HIGH_WORD(hx,x);
	ix = hx&0x7fffffff;
	if(ix>=0x7ff00000) {			/* erfc(nan)=nan */
						/* erfc(+-inf)=0,2 */
	    return (double)(((u_int32_t)hx>>31)<<1)+one/x;
	}

if(ix < 0x3feb0000) {		/* |x|<0.84375 */
	    if(ix < 0x3c700000)  	/* |x|<2**-56 */
		return one-x;
	    z = x*x;
	    r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)));
	    s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
	    y = r/s;
	    if(hx < 0x3fd00000) {  	/* x<1/4 */
		return one-(x+x*y);
	    } else {
		r = x*y;
		r += (x-half);
	        return half - r ;
	    }
	}
	if(ix < 0x3ff40000) {		/* 0.84375 <= |x| < 1.25 */
	    s = fabs(x)-one;
	    P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))));
	    Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
	    if(hx>=0) {
	        z  = one-erx; return z - P/Q;
	    } else {
		z = erx+P/Q; return one+z;
	    }
	}
	if (ix < 0x403c0000) {		/* |x|<28 */
	    x = fabs(x);
 	    s = one/(x*x);
	    if(ix< 0x4006DB6D) {	/* |x| < 1/.35 ~ 2.857143*/
		R=ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))));
		S=one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+
		    s*sa8)))))));
	    } else {			/* |x| >= 1/.35 ~ 2.857143 */
		if(hx<0&&ix>=0x40180000) return two-tiny;/* x < -6 */
		R=rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))));
		S=one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))));
	    }
	    z  = x;
	    SET_LOW_WORD(z,0);
	    r  =  __ieee754_exp(-z*z-0.5625)*__ieee754_exp((z-x)*(z+x)+R/S);
	    if(hx>0) return r/x; else return two-r/x;
	} else {
	    if(hx>0) return tiny*tiny; else return two-tiny;
	}
}

#if (LDBL_MANT_DIG == 53)
__weak_reference(erfc, erfcl);
#endif

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