75 lines
2.1 KiB
C
75 lines
2.1 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 Sebastian Pancratz
|
|
|
|
******************************************************************************/
|
|
|
|
#include "fmpq.h"
|
|
|
|
void
|
|
fmpq_set_fmpz_frac(fmpq_t res, const fmpz_t p, const fmpz_t q)
|
|
{
|
|
if (fmpz_is_zero(p))
|
|
{
|
|
fmpq_zero(res);
|
|
}
|
|
else if (fmpz_is_pm1(q) || fmpz_is_pm1(p))
|
|
{
|
|
if (fmpz_sgn(q) < 0)
|
|
{
|
|
fmpz_neg(fmpq_numref(res), p);
|
|
fmpz_neg(fmpq_denref(res), q);
|
|
}
|
|
else
|
|
{
|
|
fmpz_set(fmpq_numref(res), p);
|
|
fmpz_set(fmpq_denref(res), q);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
fmpz_t t;
|
|
|
|
fmpz_init(t);
|
|
fmpz_gcd(t, p, q);
|
|
|
|
if (fmpz_is_one(t))
|
|
{
|
|
fmpz_set(fmpq_numref(res), p);
|
|
fmpz_set(fmpq_denref(res), q);
|
|
}
|
|
else
|
|
{
|
|
fmpz_divexact(fmpq_numref(res), p, t);
|
|
fmpz_divexact(fmpq_denref(res), q, t);
|
|
}
|
|
|
|
if (fmpz_sgn(fmpq_denref(res)) < 0)
|
|
{
|
|
fmpz_neg(fmpq_numref(res), fmpq_numref(res));
|
|
fmpz_neg(fmpq_denref(res), fmpq_denref(res));
|
|
}
|
|
|
|
fmpz_clear(t);
|
|
}
|
|
}
|