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/*
Copyright (C) 2016 Pascal Molin
This file is part of FLINT.
FLINT 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 3 of the License, or
(at your option) any later version. See <https://www.gnu.org/licenses/>.
*/
#include "dirichlet.h"
void
dirichlet_char_lower(dirichlet_char_t y, const dirichlet_group_t H, const dirichlet_char_t x, const dirichlet_group_t G)
{
slong k, l;
if (G->q % H->q != 0)
{
flint_throw(FLINT_ERROR, "conrey_lower: lower modulus %wu does not divide %wu\n", H->q, G->q);
}
for (k = 0, l = 0; k < G->num && l < H->num; k++)
{
ulong p = G->P[k].p;
if (p == H->P[l].p)
{
ulong pef = n_pow(G->P[k].p, G->P[k].e - H->P[l].e);
ulong a = x->log[k];
if (a % pef)
{
flint_throw(FLINT_ERROR, "conrey_lower: conductor does not divide lower modulus %wu", H->q);
}
y->log[l] = a / pef;
l++;
}
}
_dirichlet_char_exp(y, H);
}