/*
    Copyright (C) 2010 William Hart
    Copyright (C) 2014 Abhinav Baid

    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 2.1 of the License, or
    (at your option) any later version.  See <https://www.gnu.org/licenses/>.
*/

#include "mpf_vec.h"

int
_mpf_vec_dot2(mpf_t res, const mpf * vec1, const mpf * vec2, slong len2,
              flint_bitcnt_t prec)
{
    slong i;
    int r = 0;
    mpf_t tmp, tmp2;
    mpf_init2(tmp, prec);
    mpf_init2(tmp2, prec);

    flint_mpf_set_ui(res, 0);
    for (i = 0; i < len2; i++)
    {
        mpf_mul(tmp, vec1 + i, vec2 + i);
        mpf_add(res, res, tmp);
    }

    _mpf_vec_norm(tmp, vec1, len2);
    _mpf_vec_norm(tmp2, vec2, len2);
    mpf_mul(tmp, tmp, tmp2);
    mpf_div_2exp(tmp, tmp, prec);
    mpf_mul(tmp2, res, res);

    if (mpf_cmp(tmp2, tmp) > 0)
        r = 1;

    mpf_clear(tmp);
    mpf_clear(tmp2);

    return r;
}