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1997-10-29 21:20 Ulrich Drepper <drepper@cygnus.com> * libio/strops.c (_IO_str_seekoff): If mode is zero and the read/write pointers are tied set mode according to current stream mode. * include/features.h [_GNU_SOURCE] (_POSIX_C_SOURCE): Define to 199506L. Define _XOPEN_SOURCE to 500 if _POSIX_C_SOURCE is defined. * manual/creature.texi: Describe this. * manual/socket.texi: Describe connect, accept, send, sendmsg, sendto, recv, recvfrom, and recvmsg as cancelation points. * sysdeps/unix/inet/syscalls.list: Add __libc_* names for these functions. 1997-10-17 Andreas Jaeger <aj@arthur.rhein-neckar.de> * Make-dist (try-sysdeps): Don't look for stub files anymore. * manual/maint.texi (Porting): Remove another reference to stub directory. * sysdeps/unix/bsd/sun/sethostid.c: Include stub version from generic subdir. * sysdeps/unix/sysv/irix4/reboot.c: Likewise. * sysdeps/unix/sysv/irix4/swapon.c: Likewise 1997-10-29 03:54 Ulrich Drepper <drepper@cygnus.com> * resolv/nss_dns/dns-host.c: Change variable pointed to by h_errnop in all error cases (PR 244). 1997-10-29 00:56 Ulrich Drepper <drepper@cygnus.com> * posix/glob.c: Fix handling of expressions like "*/" (PR 325). Optimize by using mempcpy. 1997-10-17 Andreas Jaeger <aj@arthur.rhein-neckar.de> * po/Makefile ($(mo-installed)): Don't fail during installation if files don't exist (might happen if msgfmt doesn't exist) (PR 328). Suggested by Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>. 1997-10-24 Andreas Jaeger <aj@arthur.rhein-neckar.de> * sysdeps/generic/bits/errno.h (ENOMSG): Define it. Pointed out by Klaus Espenlaub <kespenla@hydra.informatik.uni-ulm.de> (PR libc/259). 1997-10-28 17:40 Ulrich Drepper <drepper@cygnus.com> * sysdeps/libm-ieee754/s_cbrt.c: Testing the returned exponent for zero isn't enough to determine illegal arguments. * sysdeps/libm-ieee754/s_cbrtf.c: Likewise. * sysdeps/libm-ieee754/s_cbrtl.c: Likewise. 1997-10-28 17:14 Ulrich Drepper <drepper@cygnus.com> * manual/filesys.texi (S_ISVTX): Describe that it is available with _BSD_SOURCE only. Reported by Jochen Hein <jochen.hein@delphi.central.de>. 1997-10-28 04:26 Ulrich Drepper <drepper@cygnus.com> * time/tzfile.c (__tzfile_compute): Use negated value of offset for timezone variable. * time/tzset.c (tz_compute): Likewise. Reported by Erik Troan <ewt@redhat.com>. 1997-10-28 02:51 Ulrich Drepper <drepper@cygnus.com> * manual/filesys.texi: Correct prototype in readdir_r description. Reported by Jim Meyering <meyering@eng.ascend.com>. 1997-10-27 Andreas Jaeger <aj@arthur.rhein-neckar.de> * math/libm-test.c (cbrt_test): Add test for cbrt(0.970299). 1997-10-26 19:39 Zack Weinberg <zack@rabi.phys.columbia.edu> * stdlib/l64a.c: Produce a useful result for n < 0. * stdlib/a64l.c: Use unsigned type for working variable. * manual/string.texi (general): Grammar, typo, overfull fixes. (strlen): Insert warning about sizeof(char *). (a64l, l64a): Make documentation agree with implementation. * libio/iofdopen.c: Use _IO_FILE_complete, not _IO_FILE_plus. * posix/unistd.h: Add prototypes for __pread, __pread64, __pwrite
79 lines
2.2 KiB
C
79 lines
2.2 KiB
C
/* Compute cubic root of double value.
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Copyright (C) 1997 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Dirk Alboth <dirka@uni-paderborn.de> and
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Ulrich Drepper <drepper@cygnus.com>, 1997.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Library General Public License as
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published by the Free Software Foundation; either version 2 of the
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License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with the GNU C Library; see the file COPYING.LIB. If not,
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write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "math.h"
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#include "math_private.h"
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#define CBRT2 1.2599210498948731648 /* 2^(1/3) */
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#define SQR_CBRT2 1.5874010519681994748 /* 2^(2/3) */
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/* We don't use long double values here since U need not be computed
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with full precision. */
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static const double factor[5] =
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{
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1.0 / SQR_CBRT2,
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1.0 / CBRT2,
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1.0,
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CBRT2,
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SQR_CBRT2
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};
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long double
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__cbrtl (long double x)
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{
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long double xm, ym, u, t2;
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int xe;
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/* Reduce X. XM now is an range 1.0 to 0.5. */
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xm = __frexpl (fabs (x), &xe);
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/* If X is not finite or is null return it (with raising exceptions
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if necessary.
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Note: *Our* version of `frexp' sets XE to zero if the argument is
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Inf or NaN. This is not portable but faster. */
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if (xe == 0 && fpclassify (x) <= FP_ZERO)
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return x + x;
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u = (0.338058687610520237
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+ (1.67595307700780102
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+ (-2.82414939754975962
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+ (4.09559907378707839 +
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(-4.11151425200350531
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+ (2.65298938441952296 +
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(-0.988553671195413709
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+ 0.161617097923756032 * xm)
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* xm)
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* xm)
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* xm)
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* xm)
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* xm)
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*xm);
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t2 = u * u * u;
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ym = u * (t2 + 2.0 * xm) / (2.0 * t2 + xm) * factor[2 + xe % 3];
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return __ldexpl (x > 0.0 ? ym : -ym, xe / 3);
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}
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weak_alias (__cbrtl, cbrtl)
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