/*
Copyright (C) 2023 Jean Kieffer
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 "acb_theta.h"
void
sp2gz_restrict(fmpz_mat_t res, const fmpz_mat_t mat)
{
slong g = sp2gz_dim(mat);
slong g1 = sp2gz_dim(res);
fmpz_mat_t a, b, c, d;
fmpz_mat_window_init(a, mat, 0, 0, g1, g1);
fmpz_mat_window_init(b, mat, 0, g, g1, g + g1);
fmpz_mat_window_init(c, mat, g, 0, g + g1, g1);
fmpz_mat_window_init(d, mat, g, g, g + g1, g + g1);
sp2gz_set_blocks(res, a, b, c, d);
fmpz_mat_window_clear(a);
fmpz_mat_window_clear(b);
fmpz_mat_window_clear(c);
fmpz_mat_window_clear(d);
}