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Diffstat (limited to 'sysdeps/ieee754/dbl-64/mplog.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/mplog.c | 65 |
1 files changed, 0 insertions, 65 deletions
diff --git a/sysdeps/ieee754/dbl-64/mplog.c b/sysdeps/ieee754/dbl-64/mplog.c deleted file mode 100644 index f6cd5f4aa1..0000000000 --- a/sysdeps/ieee754/dbl-64/mplog.c +++ /dev/null @@ -1,65 +0,0 @@ -/* - * IBM Accurate Mathematical Library - * written by International Business Machines Corp. - * Copyright (C) 2001-2018 Free Software Foundation, Inc. - * - * This program 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. - * - * This program 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 this program; if not, see <http://www.gnu.org/licenses/>. - */ -/************************************************************************/ -/* */ -/* MODULE_NAME:mplog.c */ -/* */ -/* FUNCTIONS: mplog */ -/* */ -/* FILES NEEDED: endian.h mpa.h mplog.h */ -/* mpexp.c */ -/* */ -/* Multi-Precision logarithm function subroutine (for precision p >= 4, */ -/* 2**(-1024) < x < 2**1024) and x is outside of the interval */ -/* [1-2**(-54),1+2**(-54)]. Upon entry, x should be set to the */ -/* multi-precision value of the input and y should be set into a multi- */ -/* precision value of an approximation of log(x) with relative error */ -/* bound of at most 2**(-52). The routine improves the accuracy of y. */ -/* */ -/************************************************************************/ -#include "endian.h" -#include "mpa.h" - -void -__mplog (mp_no *x, mp_no *y, int p) -{ - int i, m; - static const int mp[33] = - { - 0, 0, 0, 0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, - 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 - }; - mp_no mpt1, mpt2; - - /* Choose m. */ - m = mp[p]; - - /* Perform m newton iterations to solve for y: exp(y) - x = 0. The - iterations formula is: y(n + 1) = y(n) + (x * exp(-y(n)) - 1). */ - __cpy (y, &mpt1, p); - for (i = 0; i < m; i++) - { - mpt1.d[0] = -mpt1.d[0]; - __mpexp (&mpt1, &mpt2, p); - __mul (x, &mpt2, &mpt1, p); - __sub (&mpt1, &__mpone, &mpt2, p); - __add (y, &mpt2, &mpt1, p); - __cpy (&mpt1, y, p); - } -} |