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/*
Copyright (C) 2013 Mike Hansen
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 "ulong_extras.h"
#include "fq_zech.h"
void
fq_zech_frobenius(fq_zech_t rop, const fq_zech_t op, slong e,
const fq_zech_ctx_t ctx)
{
double qm1_inv;
slong d = fq_zech_ctx_degree(ctx);
e = e % d;
if (e < 0)
e += d;
if (fq_zech_is_zero(op, ctx))
{
fq_zech_zero(rop, ctx);
}
else if (e == 0)
{
fq_zech_set(rop, op, ctx);
}
else
{
qm1_inv = n_precompute_inverse(ctx->qm1);
e = n_powmod(ctx->p, e, ctx->qm1);
rop->value = n_mulmod_precomp(op->value, e, ctx->qm1, qm1_inv);
}
}