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

74 lines
2.4 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 Fredrik Johansson
******************************************************************************/
#include "flint.h"
#include "ulong_extras.h"
#include "nmod_mat.h"
#include "nmod_vec.h"
void
nmod_mat_randops(nmod_mat_t mat, slong count, flint_rand_t state)
{
slong c, i, j, k;
slong m = mat->r;
slong n = mat->c;
if (mat->r == 0 || mat->c == 0)
return;
for (c = 0; c < count; c++)
{
if (n_randint(state, 2))
{
if ((i = n_randint(state, m)) == (j = n_randint(state, m)))
continue;
if (n_randint(state, 2))
for (k = 0; k < n; k++)
mat->rows[j][k] = nmod_add(mat->rows[j][k],
mat->rows[i][k], mat->mod);
else
for (k = 0; k < n; k++)
mat->rows[j][k] = nmod_sub(mat->rows[j][k],
mat->rows[i][k], mat->mod);
}
else
{
if ((i = n_randint(state, n)) == (j = n_randint(state, n)))
continue;
if (n_randint(state, 2))
for (k = 0; k < m; k++)
mat->rows[k][j] = nmod_add(mat->rows[k][j],
mat->rows[k][i], mat->mod);
else
for (k = 0; k < m; k++)
mat->rows[k][j] = nmod_sub(mat->rows[k][j],
mat->rows[k][i], mat->mod);
}
}
}