arb/dlog/vec_eratos.c
Pascal 5ecc8e1f25 dlog vec performs as it should
but still mathematically not debugged
2016-09-06 14:24:01 +02:00

58 lines
2 KiB
C

/*=============================================================================
This file is part of ARB.
ARB 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.
ARB 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 ARB; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2016 Pascal Molin
******************************************************************************/
#include "dlog.h"
void
dlog_vec_eratos_ph(ulong *v, ulong nv, ulong a, ulong va, ulong M, nmod_t mod, ulong na, nmod_t order)
{
ulong p, pmax;
dlog_precomp_t pre;
n_primes_t iter;
/* discrete log on primes */
pmax = (nv < mod.n) ? nv : mod.n;
dlog_precomp_n_init(pre, a, mod.n, na, n_prime_pi(nv));
n_primes_init(iter);
while ((p = n_primes_next(iter)) < pmax)
{
ulong k, pM, wp;
if (mod.n % p == 0)
continue; /* won't be attained another time */
pM = (M) ? nmod_pow_ui(p, M, mod) : p;
wp = nmod_mul(dlog_precomp(pre, pM), va, order);
for (pM = p; pM < nv; pM *= p)
for (k = pM; k < nv; k += pM)
v[k] = nmod_add(v[k], wp, order);
}
n_primes_clear(iter);
}
void
dlog_vec_eratos(ulong *v, ulong nv, ulong a, ulong va, nmod_t mod, ulong na, nmod_t order)
{
dlog_vec_eratos_ph(v, nv, a, va, 1, mod, na, order);
}