arb/dirichlet/char_exp.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"

ulong
_dirichlet_char_exp(dirichlet_char_t x, const dirichlet_group_t G)
{
    ulong k, n = 1;
    for (k = 0; k < G->num; k++)
        n = nmod_mul(n, nmod_pow_ui(G->generators[k], x->log[k], G->mod), G->mod);
    x->n = n;
    return n;
}