arb/acb_dirichlet/charevalvec.c
2016-10-08 22:45:58 +02:00

132 lines
3.3 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) 2015 Jonathan Bober
Copyright (C) 2016 Fredrik Johansson
******************************************************************************/
#include "acb_dirichlet.h"
static void
set_non_invertible_values(long *v, const acb_dirichlet_group_t G, ulong nv)
{
ulong k, l;
if (G->q_even > 1)
{
for (k = 2; k < nv; k += 2)
v[k] = -1;
}
for (l = 0; l < G->num; l++)
{
ulong p = G->primes[l];
for (k = p; k < nv; k += p)
v[k] = -1;
}
}
/* loop over whole group */
void
n_dirichlet_char_vec_loop(long *v, const acb_dirichlet_group_t G, const acb_dirichlet_char_t chi, ulong nv)
{
int j;
ulong t, k;
acb_conrey_t x;
acb_conrey_init(x, G);
acb_conrey_one(x, G);
t = v[1] = 0;
while ( (j = acb_conrey_next(x, G)) < G->num )
{
/* exponents were modified up to j */
for (k = 0; k < j; k++)
t = (t + chi->expo[k] * x->log[k]) % chi->order;
if (x->n < nv)
v[x->n] = t;
}
/* fix result outside primes */
set_non_invertible_values(v, G, nv);
/* copy outside modulus */
for (k = G->q + 1; k < nv ; k++ )
v[k] = v[k - G->q];
acb_conrey_clear(x);
}
/* loop over primary components */
void
n_dirichlet_char_vec_primeloop(long *v, const acb_dirichlet_group_t G, const acb_dirichlet_char_t chi, ulong nv)
{
ulong k, l;
for(k = 1; k < nv; ++k)
v[k] = 0;
for(l = 1; l < G->num; ++l)
{
long p, pe, g, x, vp, xp;
long j, vj;
p = G->primes[l];
pe = G->primepowers[l];
g = G->generators[l] % pe;
vj = vp = chi->expo[l];
/* for each x = g^j mod p^e,
* set a[x] += j*vp
* and use periodicity */
for(j = 1, x = g; x > 1; j++)
{
for(xp = x; xp < nv; xp+=pe)
v[xp] = (v[xp] + vj) % chi->order;
x = (x*g) % pe;
vj = (vj + vp) % chi->order;
}
}
set_non_invertible_values(v, G, nv);
}
/* eratosthene sieve on primes */
void
n_dirichlet_char_vec_logsieve(long *v, const acb_dirichlet_group_t G, const acb_dirichlet_char_t chi, ulong nv)
{
ulong k, p, pmax;
n_primes_t iter;
n_primes_init(iter);
pmax = (nv < G->q) ? nv : G->q;
v[1] = 0;
while ((p = n_primes_next(iter)) < pmax)
{
if (G->q % p == 0)
{
for (k = p; k < nv; k += p)
v[k] = -1;
}
else
{
long chip;
chip = n_dirichlet_char_eval(G, chi, p);
for (k = p; k < nv; k += p)
if (v[k] != -1)
v[k] = (v[k] + chip) % chi->order;
}
}
n_primes_clear(iter);
}