56 lines
1.8 KiB
C
56 lines
1.8 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
|
|
Copyright (C) 2010, 2012 Sebastian Pancratz
|
|
|
|
******************************************************************************/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <gmp.h>
|
|
#include "flint.h"
|
|
#include "ulong_extras.h"
|
|
#include "fmpz.h"
|
|
|
|
void
|
|
fmpz_randm(fmpz_t f, flint_rand_t state, const fmpz_t m)
|
|
{
|
|
mp_bitcnt_t bits = fmpz_bits(m);
|
|
int sgn = fmpz_sgn(m);
|
|
|
|
if (bits <= FLINT_BITS - 2)
|
|
{
|
|
_fmpz_demote(f);
|
|
*f = (sgn >= 0) ? n_randint(state, *m) : - n_randint(state, -(*m));
|
|
}
|
|
else
|
|
{
|
|
__mpz_struct *mpz_ptr = _fmpz_promote(f);
|
|
|
|
_flint_rand_init_gmp(state);
|
|
mpz_urandomm(mpz_ptr, state->gmp_state, COEFF_TO_PTR(*m));
|
|
if (sgn < 0)
|
|
mpz_neg(mpz_ptr, mpz_ptr);
|
|
_fmpz_demote_val(f);
|
|
}
|
|
}
|