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

64 lines
1.8 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) 2008, 2009 William Hart
******************************************************************************/
#include <gmp.h>
#include "flint.h"
#include "fmpz.h"
#include "fmpz_poly.h"
void
fmpz_poly_scalar_mul_si(fmpz_poly_t poly1, const fmpz_poly_t poly2, slong x)
{
slong i;
/* Either scalar or input poly is zero */
if ((x == WORD(0)) || (poly2->length == 0))
{
fmpz_poly_zero(poly1);
return;
}
/* Special case, multiply by 1 */
if (x == WORD(1))
{
fmpz_poly_set(poly1, poly2);
return;
}
/* Special case, multiply by -1 */
if (x == WORD(-1))
{
fmpz_poly_neg(poly1, poly2);
return;
}
fmpz_poly_fit_length(poly1, poly2->length);
for (i = 0; i < poly2->length; i++)
fmpz_mul_si(poly1->coeffs + i, poly2->coeffs + i, x);
_fmpz_poly_set_length(poly1, poly2->length);
}