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

117 lines
3.3 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) 2009 William Hart
******************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <gmp.h>
#include "flint.h"
#include "fmpz.h"
#include "fmpz_poly.h"
#include "ulong_extras.h"
int
main(void)
{
int i, result;
FLINT_TEST_INIT(state);
flint_printf("inv_series_newton....");
fflush(stdout);
/* Check Q^{-1} * Q is congruent 1 mod t^n */
for (i = 0; i < 100 * flint_test_multiplier(); i++)
{
fmpz_poly_t a, b, c, one;
slong n = n_randint(state, 80) + 1;
fmpz_poly_init(a);
fmpz_poly_init(b);
fmpz_poly_init(c);
fmpz_poly_init(one);
fmpz_poly_randtest_not_zero(a, state, n_randint(state, 80) + 1, 100);
fmpz_poly_set_coeff_si(a, 0, n_randint(state, 2) ? 1 : -1);
fmpz_poly_set_ui(one, 1);
fmpz_poly_inv_series_newton(b, a, n);
fmpz_poly_mullow(c, a, b, n);
result = (fmpz_poly_equal(c, one));
if (!result)
{
flint_printf("FAIL:\n");
flint_printf("a = "), fmpz_poly_print(a), flint_printf("\n\n");
flint_printf("b = "), fmpz_poly_print(b), flint_printf("\n\n");
flint_printf("c = "), fmpz_poly_print(c), flint_printf("\n\n");
abort();
}
fmpz_poly_clear(a);
fmpz_poly_clear(b);
fmpz_poly_clear(c);
fmpz_poly_clear(one);
}
/* Verify bug fix for the case Q = -1 mod (x) */
{
fmpz_poly_t a, b, c, one;
slong n = 1;
fmpz_poly_init(a);
fmpz_poly_init(b);
fmpz_poly_init(c);
fmpz_poly_init(one);
fmpz_poly_set_si(a, -1);
fmpz_poly_set_ui(one, 1);
fmpz_poly_inv_series_newton(b, a, n);
fmpz_poly_mullow(c, a, b, n);
result = (fmpz_poly_equal(c, one));
if (!result)
{
flint_printf("FAIL:\n");
flint_printf("a = "), fmpz_poly_print(a), flint_printf("\n\n");
flint_printf("b = "), fmpz_poly_print(b), flint_printf("\n\n");
flint_printf("c = "), fmpz_poly_print(c), flint_printf("\n\n");
abort();
}
fmpz_poly_clear(a);
fmpz_poly_clear(b);
fmpz_poly_clear(c);
fmpz_poly_clear(one);
}
FLINT_TEST_CLEANUP(state);
flint_printf("PASS\n");
return 0;
}