pqc/external/flint-2.4.3/nmod_poly_mat/det_fflu.c

53 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 "flint.h"
#include "nmod_poly.h"
#include "nmod_poly_mat.h"
#include "perm.h"
void
nmod_poly_mat_det_fflu(nmod_poly_t det, const nmod_poly_mat_t A)
{
slong n = nmod_poly_mat_nrows(A);
if (n == 0)
nmod_poly_one(det);
else
{
nmod_poly_mat_t tmp;
slong * perm;
nmod_poly_mat_init_set(tmp, A);
perm = _perm_init(n);
nmod_poly_mat_fflu(tmp, det, perm, tmp, 1);
if (_perm_parity(perm, n))
nmod_poly_neg(det, det);
_perm_clear(perm);
nmod_poly_mat_clear(tmp);
}
}