pqc/external/flint-2.4.3/fmpq/set_si.c

55 lines
1.6 KiB
C

/*=============================================================================
This file is part of FLINT.
FLINT 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.
FLINT 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 FLINT; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2011 Fredrik Johansson
******************************************************************************/
#include "fmpq.h"
void _fmpq_set_si(fmpz_t rnum, fmpz_t rden, slong p, ulong q)
{
if (q == 1 || p == 0)
{
fmpz_set_si(rnum, p);
fmpz_one(rden);
}
else
{
ulong r = n_gcd_full(p < 0 ? (-(ulong) p) : (ulong) p, q);
if (p < 0)
{
fmpz_set_ui(rnum, (-(ulong) p) / r);
fmpz_neg(rnum, rnum);
}
else
fmpz_set_si(rnum, p / r);
fmpz_set_ui(rden, q / r);
}
}
void fmpq_set_si(fmpq_t res, slong p, ulong q)
{
_fmpq_set_si(fmpq_numref(res), fmpq_denref(res), p, q);
}