/*=============================================================================

    This file is part of ARB.

    ARB is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    ARB is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with ARB; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

=============================================================================*/
/******************************************************************************

    Copyright (C) 2016 Pascal Molin

******************************************************************************/

#include "acb_dirichlet.h"
#include "acb_poly.h"

/* assume a[0] = 0 */
void
acb_dirichlet_qseries_eval_arb(acb_t res, acb_srcptr a, const arb_t x, slong len, slong prec)
{
    slong k;
    arb_t xk2, dx, x2;

    arb_init(xk2);
    arb_init(dx);
    arb_init(x2);

    arb_set(dx, x);
    arb_set(xk2, dx);
    arb_mul(x2, dx, dx, prec);

    acb_mul_arb(res, a + 1, xk2, prec);

    /* TODO: reduce prec */
    for (k = 2; k < len; k++)
    {
        arb_mul(dx, dx, x2, prec);
        arb_mul(xk2, xk2, dx, prec);
        acb_addmul_arb(res, a + k, xk2, prec);
    }

    arb_clear(xk2);
    arb_clear(x2);
    arb_clear(dx);
}