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/*
Copyright (C) 2021 Daniel Schultz
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 "mpn_extras.h"
#include "mpoly.h"
#include "fmpz_vec.h"
#include "fmpz_mod_mpoly.h"
void fmpz_mod_mpoly_resize(fmpz_mod_mpoly_t A, slong new_length,
const fmpz_mod_mpoly_ctx_t ctx)
{
slong old_length = A->length;
slong N = mpoly_words_per_exp(A->bits, ctx->minfo);
new_length = FLINT_MAX(WORD(0), new_length);
if (new_length > old_length)
{
fmpz_mod_mpoly_fit_length(A, new_length, ctx);
/* must zero out the new coeffs/exps past the old end */
flint_mpn_zero(A->exps + N*old_length, N*(new_length - old_length));
_fmpz_vec_zero(A->coeffs + old_length, new_length - old_length);
}
else if (new_length < old_length)
{
/* just zero out the extra unused fmpz's past the new end */
_fmpz_vec_zero(A->coeffs + new_length, old_length - new_length);
}
A->length = new_length;
}