arb/fmpr/abs_bound_lt_2exp_si.c
2015-11-05 18:03:08 +00:00

60 lines
1.7 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) 2013 Fredrik Johansson
******************************************************************************/
#include "fmpr.h"
long
fmpr_abs_bound_lt_2exp_si(const fmpr_t x)
{
if (fmpr_is_special(x))
{
if (fmpr_is_zero(x))
return -FMPR_PREC_EXACT;
else
return FMPR_PREC_EXACT;
}
else
{
slong res;
fmpz_t t;
fmpz_init(t);
fmpr_abs_bound_lt_2exp_fmpz(t, x);
if (fmpz_fits_si(t))
res = fmpz_get_si(t);
else
res = fmpz_sgn(t) < 0 ? -FMPR_PREC_EXACT : FMPR_PREC_EXACT;
fmpz_clear(t);
if (res < -FMPR_PREC_EXACT)
res = -FMPR_PREC_EXACT;
if (res > FMPR_PREC_EXACT)
res = FMPR_PREC_EXACT;
return res;
}
}