pqc/external/flint-2.4.3/fmpz_mat/CRT_ui.c

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2014-05-18 22:03:37 +00:00
/*=============================================================================
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 "fmpz_mat.h"
void
fmpz_mat_CRT_ui(fmpz_mat_t res, const fmpz_mat_t mat1,
const fmpz_t m1, const nmod_mat_t mat2, int sign)
{
slong i, j;
mp_limb_t c;
mp_limb_t m2 = mat2->mod.n;
mp_limb_t m2inv = mat2->mod.ninv;
fmpz_t m1m2;
c = fmpz_fdiv_ui(m1, m2);
c = n_invmod(c, m2);
if (c == 0)
{
flint_printf("Exception (fmpz_mat_CRT_ui). m1 not invertible modulo m2.\n");
abort();
}
fmpz_init(m1m2);
fmpz_mul_ui(m1m2, m1, m2);
for (i = 0; i < mat1->r; i++)
{
for (j = 0; j < mat1->c; j++)
_fmpz_CRT_ui_precomp(fmpz_mat_entry(res, i, j),
fmpz_mat_entry(mat1, i, j), m1,
nmod_mat_entry(mat2, i, j), m2, m2inv, m1m2, c, sign);
}
fmpz_clear(m1m2);
}