Mercurial > hg > CbC > CbC_gcc
view libquadmath/math/clogq.c @ 120:f93fa5091070
fix conv1.c
author | mir3636 |
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date | Thu, 08 Mar 2018 14:53:42 +0900 |
parents | 04ced10e8804 |
children | 1830386684a0 |
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/* Compute complex natural logarithm for complex __float128. Copyright (C) 1997-2012 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #include "quadmath-imp.h" __complex128 clogq (__complex128 x) { __complex128 result; int rcls = fpclassifyq (__real__ x); int icls = fpclassifyq (__imag__ x); if (__builtin_expect (rcls == QUADFP_ZERO && icls == QUADFP_ZERO, 0)) { /* Real and imaginary part are 0.0. */ __imag__ result = signbitq (__real__ x) ? M_PIq : 0.0Q; __imag__ result = copysignq (__imag__ result, __imag__ x); /* Yes, the following line raises an exception. */ __real__ result = -1.0Q / fabsq (__real__ x); } else if (__builtin_expect (rcls != QUADFP_NAN && icls != QUADFP_NAN, 1)) { /* Neither real nor imaginary part is NaN. */ __float128 absx = fabsq (__real__ x), absy = fabsq (__imag__ x); int scale = 0; if (absx < absy) { __float128 t = absx; absx = absy; absy = t; } if (absx > FLT128_MAX / 2.0) { scale = -1; absx = scalbnq (absx, scale); absy = (absy >= FLT128_MIN * 2.0Q ? scalbnq (absy, scale) : 0.0Q); } else if (absx < FLT128_MIN && absy < FLT128_MIN) { scale = FLT128_MANT_DIG; absx = scalbnq (absx, scale); absy = scalbnq (absy, scale); } if (absx == 1.0Q && scale == 0) { __float128 absy2 = absy * absy; if (absy2 <= FLT128_MIN * 2.0Q) __real__ result = absy2 / 2.0Q - absy2 * absy2 / 4.0Q; else __real__ result = log1pq (absy2) / 2.0Q; } else if (absx > 1.0Q && absx < 2.0Q && absy < 1.0Q && scale == 0) { __float128 d2m1 = (absx - 1.0Q) * (absx + 1.0Q); if (absy >= FLT128_EPSILON) d2m1 += absy * absy; __real__ result = log1pq (d2m1) / 2.0Q; } else if (absx < 1.0Q && absx >= 0.75Q && absy < FLT128_EPSILON / 2.0Q && scale == 0) { __float128 d2m1 = (absx - 1.0Q) * (absx + 1.0Q); __real__ result = log1pq (d2m1) / 2.0Q; } else if (absx < 1.0 && (absx >= 0.75Q || absy >= 0.5Q) && scale == 0) { __float128 d2m1 = __quadmath_x2y2m1q (absx, absy); __real__ result = log1pq (d2m1) / 2.0Q; } else { __float128 d = hypotq (absx, absy); __real__ result = logq (d) - scale * M_LN2q; } __imag__ result = atan2q (__imag__ x, __real__ x); } else { __imag__ result = nanq (""); if (rcls == QUADFP_INFINITE || icls == QUADFP_INFINITE) /* Real or imaginary part is infinite. */ __real__ result = HUGE_VALQ; else __real__ result = nanq (""); } return result; }