arb/dirichlet/char_next.c
2016-11-18 12:33:03 +01:00

29 lines
771 B
C

/*
Copyright (C) 2016 Pascal Molin
This file is part of Arb.
Arb is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version. See <http://www.gnu.org/licenses/>.
*/
#include "dirichlet.h"
int
dirichlet_char_next(dirichlet_char_t x, const dirichlet_group_t G)
{
/* update index */
int k;
for (k = G->num - 1; k >= 0; k--)
{
x->n = nmod_mul(x->n, G->generators[k], G->mod);
x->log[k] += 1;
if (x->log[k] < G->P[k].phi.n)
break;
x->log[k] = 0;
}
/* return last index modified */
return k;
}