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

62 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) 2007, David Howden.
Copyright (C) 2010 William Hart
******************************************************************************/
#include <gmp.h>
#include "flint.h"
#include "nmod_vec.h"
#include "nmod_poly.h"
void nmod_poly_set_coeff_ui(nmod_poly_t poly, slong j, ulong c)
{
if (c >= poly->mod.n)
NMOD_RED(c, c, poly->mod);
nmod_poly_fit_length(poly, j + 1);
if (j + 1 < poly->length) /* interior */
poly->coeffs[j] = c;
else if (j + 1 == poly->length) /* leadiung coeff */
{
if (c != 0)
poly->coeffs[j] = c;
else
{
poly->length--;
_nmod_poly_normalise(poly);
}
} else /* extend polynomial */
{
if (c == 0) return;
else
{
flint_mpn_zero(poly->coeffs + poly->length, j - poly->length);
poly->coeffs[j] = c;
poly->length = j + 1;
}
}
}