mirror of
https://github.com/vale981/arb
synced 2025-03-06 09:51:39 -05:00
80 lines
2.3 KiB
C
80 lines
2.3 KiB
C
/*=============================================================================
|
|
|
|
This file is part of ARB.
|
|
|
|
ARB is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
ARB 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with ARB; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
=============================================================================*/
|
|
/******************************************************************************
|
|
|
|
Copyright (C) 2015 Fredrik Johansson
|
|
|
|
******************************************************************************/
|
|
|
|
#include "acb.h"
|
|
|
|
slong
|
|
acb_rel_error_bits(const acb_t x)
|
|
{
|
|
int am, ar, bm, br;
|
|
slong result;
|
|
const fmpz * radmag;
|
|
const fmpz * midmag;
|
|
fmpz_t t;
|
|
|
|
am = !arf_is_zero(arb_midref(acb_realref(x)));
|
|
ar = !mag_is_zero(arb_radref(acb_realref(x)));
|
|
|
|
bm = !arf_is_zero(arb_midref(acb_imagref(x)));
|
|
br = !mag_is_zero(arb_radref(acb_imagref(x)));
|
|
|
|
/* no radius -- exact */
|
|
if (!ar && !br)
|
|
return -ARF_PREC_EXACT;
|
|
|
|
/* no midpoint -- infinite relative error */
|
|
if (!am && !bm)
|
|
return ARF_PREC_EXACT;
|
|
|
|
if (!acb_is_finite(x))
|
|
return ARF_PREC_EXACT;
|
|
|
|
#define ame ARF_EXPREF(arb_midref(acb_realref(x)))
|
|
#define are MAG_EXPREF(arb_radref(acb_realref(x)))
|
|
#define bme ARF_EXPREF(arb_midref(acb_imagref(x)))
|
|
#define bre MAG_EXPREF(arb_radref(acb_imagref(x)))
|
|
|
|
if (am && bm)
|
|
midmag = fmpz_cmp(ame, bme) >= 0 ? ame : bme;
|
|
else if (am)
|
|
midmag = ame;
|
|
else
|
|
midmag = bme;
|
|
|
|
if (ar && br)
|
|
radmag = fmpz_cmp(are, bre) >= 0 ? are : bre;
|
|
else if (ar)
|
|
radmag = are;
|
|
else
|
|
radmag = bre;
|
|
|
|
fmpz_init(t);
|
|
fmpz_add_ui(t, radmag, 1);
|
|
result = _fmpz_sub_small(t, midmag);
|
|
fmpz_clear(t);
|
|
|
|
return result;
|
|
}
|
|
|