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

121 lines
3.1 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 <stdio.h>
#include <stdlib.h>
#include <gmp.h>
#include <mpfr.h>
#include "flint.h"
#include "arith.h"
#include "fmpz_vec.h"
#include "ulong_extras.h"
int main(void)
{
fmpz * b1;
fmpz * b2;
slong n, k;
const slong maxn = 400;
FLINT_TEST_INIT(state);
flint_printf("bell_number....");
fflush(stdout);
b1 = _fmpz_vec_init(maxn);
/* Consistency test */
for (n = 0; n < maxn; n++)
arith_bell_number(b1 + n, n);
for (n = 0; n < maxn; n++)
{
b2 = _fmpz_vec_init(n);
arith_bell_number_vec(b2, n);
if (!_fmpz_vec_equal(b1, b2, n))
{
flint_printf("FAIL:\n");
flint_printf("n = %wd\n", n);
abort();
}
_fmpz_vec_clear(b2, n);
}
/* Compare with B_n = sum of Stirling numbers of 2nd kind */
for (n = 0; n < 1000; n += (n < 50) ? + 1 : n/4)
{
b2 = _fmpz_vec_init(n+1);
arith_stirling_number_2_vec(b2, n, n+1);
for (k = 1; k <= n; k++)
fmpz_add(b2, b2, b2 + k);
arith_bell_number(b1, n);
if (!fmpz_equal(b1, b2))
{
flint_printf("FAIL:\n");
flint_printf("n = %wd\n", n);
fmpz_print(b1);
flint_printf("\n");
fmpz_print(b2);
flint_printf("\n");
abort();
}
/* Also check nmod value */
{
nmod_t mod;
mp_limb_t bb;
nmod_init(&mod, n_randtest_prime(state, 0));
bb = arith_bell_number_nmod(n, mod);
if (fmpz_fdiv_ui(b1, mod.n) != bb)
{
flint_printf("FAIL:\n");
flint_printf("n = %wd\n", n);
fmpz_print(b1);
flint_printf("\n");
flint_printf("should be %wu mod %wu\n", bb, mod.n);
abort();
}
}
_fmpz_vec_clear(b2, n+1);
}
_fmpz_vec_clear(b1, maxn);
FLINT_TEST_CLEANUP(state);
flint_printf("PASS\n");
return 0;
}