glibc/sysdeps/libm-ieee754/s_cbrt.c
Ulrich Drepper 26dee9c49c Update.
1997-04-05 03:11  Ulrich Drepper  <drepper@cygnus.com>

	* inet/arpa/inet.h: Rewrite.  Don't use the ugly BSD way to write
	headers but instead add comments and parameter names.
	Don't use BSD specific types in prototypes.

	* manual/nss.texi: Correct a few typos and errors.

	* sysdeps/libm-ieee754/s_cbrt.c: Complete rewrite based on better
	algorithm.
	* sysdeps/libm-ieee754/s_cbrtf.c: Likewise.
	* sysdeps/libm-ieee754/s_cbrtl.c: Likewise.

	* sysdeps/libm-i387/s_cbrt.S: New file.  Optimized assembler version
	with new algorithm.
	* sysdeps/libm-i387/s_cbrtf.S: New file.
	* sysdeps/libm-i387/s_cbrtl.S: New file.

	* sysdeps/libm-i387/s_frexp.S: Optimize even more.
	* sysdeps/libm-i387/s_frexpf.S: Likewise.
	* sysdeps/libm-i387/s_frexpl.S: Likewise.

1997-04-04 18:55  Thorsten Kukuk  <kukuk@vt.uni-paderborn.de>

	* nis/Makefile: Remove CFLAGS-*, add publickey to databases.

	* nis/nis_call.c: Add MASTER_ONLY and HARD_LOOKUP flags, compile
	DES part only with secure RPC add-on.

	* nis/nis_names.c (nis_modify): Fix rpc function number.

	* nis/nis_server.c: Fix typos.

	* nis/nss_compat/compat-grp.c: Add NIS+ support.
	* nis/nss_compat/compat-pwd.c: Likewise.
	* nis/nss_compat/compat-spwd.c: Likewise.

	* nis/nss_nis/nis-grp.c: Only a return value > 0 from parse_line
	signals success.

	* nis/nss_nis/nis-publickey.c: Changes for compiling with/without
	secure RPC.
	* nis/nss_nisplus/nisplus-publickey.c: Likewise.
	* nis/ypclnt.c: Likewise.
	* nis/nis_intern.h: Likewise.

	* nis/nss_nisplus/nisplus-alias.c: Correct parser return code.
	* nis/nss_nisplus/nisplus-ethers.c: Likewise.
	* nis/nss_nisplus/nisplus-hosts.c: Likewise.
	* nis/nss_nisplus/nisplus-network.c: Likewise.
	* nis/nss_nisplus/nisplus-proto.c: Likewise.
	* nis/nss_nisplus/nisplus-pwd.c: Likewise.
	* nis/nss_nisplus/nisplus-rpc.c: Likewise.
	* nis/nss_nisplus/nisplus-service.c: Likewise.
	* nis/nss_nisplus/nisplus-spwd.c: Likewise.

	* nis/nss_nisplus/nisplus-grp.c: Rewrite parser for fixing errors
	and speedup.
	* nis/nss_nisplus/nisplus-netgrp.c: Likewise.

1997-04-04 17:03  Ulrich Drepper  <drepper@cygnus.com>

	* math/libm-test.c (cbrt_test): Add tests for +-inf and NaN
	arguments.

1997-04-03 19:24  H.J. Lu  <hjl@gnu.ai.mit.edu>

	* sysdeps/unix/sysv/linux/sigset.h (__sigisemptyset): Fix a
	typo.

1997-04-03 16:10  Andreas Jaeger  <aj@arthur.pfalz.de>

	* sysdeps/libm-ieee754/s_nanf.c:
	* sysdeps/libm-ieee754/s_nan.c:
	* sysdeps/libm-ieee754/s_nanl.c: Include <stdio.h> for
	declaration of sprintf.

1997-04-03 13:37  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/libm-ieee754/s_cexp.c: Fix type: string_alias ->
	strong_alias.
	Reported by sun <asun@zoology.washington.edu>.

	* rpc/auth.h: Removed.
	* rpc/auth_des.h: Removed.
	* sunrpc/rpc/auth.h: Moved to ...
	* sysdeps/generic/rpc/auth.h: ...here.
	* sunrpc/rpc/auth_des.h: Moved to ...
	* sysdeps/generic/rpc/auth_des.h: ...here.

1997-04-03 04:28  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/libm-i387/s_frexp.S: New file.  ix87 optimized version.
	* sysdeps/libm-i387/s_frexpf.S: New file.
	* sysdeps/libm-i387/s_frexpl.S: New file.

1997-04-01 10:11  H.J. Lu  <hjl@gnu.ai.mit.edu>

	* sysdeps/unix/sysv/linux/Makefile [$(subdir)=inet]
	(sysdep_headers): Remove netinet/icmp.h.

	Describe `inf', `infinity', `nan', `nan(...)' inputs for strtod
	* sysdeps/i386/memcmp.S: Likewise.
	* time/antarctica: Likewise.
	* time/australasia: Likewise.
1997-04-05 01:26:47 +00:00

75 lines
2.0 KiB
C

/* Compute cubic root of double value.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Dirk Alboth <dirka@uni-paderborn.de> and
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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "math.h"
#include "math_private.h"
#define CBRT2 1.2599210498948731648 /* 2^(1/3) */
#define SQR_CBRT2 1.5874010519681994748 /* 2^(2/3) */
static const double factor[5] =
{
1.0 / SQR_CBRT2,
1.0 / CBRT2,
1.0,
CBRT2,
SQR_CBRT2
};
double
__cbrt (double x)
{
double xm, ym, u, t2;
int xe;
/* Reduce X. XM now is an range 1.0 to 0.5. */
xm = __frexp (fabs (x), &xe);
/* If X is not finite or is null return it (with raising exceptions
if necessary. */
if (xe == 0)
return x + x;
u = (0.354895765043919860
+ ((1.50819193781584896
+ ((-2.11499494167371287
+ ((2.44693122563534430
+ ((-1.83469277483613086
+ (0.784932344976639262 - 0.145263899385486377 * xm) * xm)
* xm))
* xm))
* xm))
* xm));
t2 = u * u * u;
ym = u * (t2 + 2.0 * xm) / (2.0 * t2 + xm) * factor[2 + xe % 3];
return __ldexp (x > 0.0 ? ym : -ym, xe / 3);
}
weak_alias (__cbrt, cbrt)
#ifdef NO_LONG_DOUBLE
strong_alias (__cbrt, __cbrtl)
weak_alias (__cbrt, cbrtl)
#endif