pqc/external/flint-2.4.3/fmpq_poly/set_coeff_ui.c
2014-05-24 23:16:06 +02:00

63 lines
1.9 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) 2010 Sebastian Pancratz
Copyright (C) 2010 William Hart
******************************************************************************/
#include <stdlib.h>
#include <gmp.h>
#include "flint.h"
#include "fmpz.h"
#include "fmpq_poly.h"
void fmpq_poly_set_coeff_ui(fmpq_poly_t poly, slong n, ulong x)
{
slong len = poly->length;
const int replace = (n < len && !fmpz_is_zero(poly->coeffs + n));
if (!replace && (x == UWORD(0)))
return;
if (n + 1 > len)
{
fmpq_poly_fit_length(poly, n + 1);
_fmpq_poly_set_length(poly, n + 1);
flint_mpn_zero((mp_ptr) poly->coeffs + len, (n + 1) - len);
}
if (*poly->den == WORD(1))
{
fmpz_set_ui(poly->coeffs + n, x);
if (replace)
_fmpq_poly_normalise(poly);
}
else
{
fmpz_mul_ui(poly->coeffs + n, poly->den, x);
if (replace)
fmpq_poly_canonicalise(poly);
}
}