mirror of
https://github.com/vale981/arb
synced 2025-03-04 17:01:40 -05:00
62 lines
1.4 KiB
C
62 lines
1.4 KiB
C
/*
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Copyright (C) 2016 Fredrik Johansson
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Copyright (C) 2016 Pascal Molin
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This file is part of Arb.
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Arb is free software: you can redistribute it and/or modify it under
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the terms of the GNU Lesser General Public License (LGPL) as published
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by the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version. See <http://www.gnu.org/licenses/>.
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*/
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#include "acb_dirichlet.h"
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/* bsgs evaluation */
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void
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acb_dirichlet_si_poly_evaluate(acb_t res, slong * v, slong len, const acb_t z, slong prec)
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{
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slong k, r, m;
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acb_t sq;
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acb_ptr zk;
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if (len < 3)
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{
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if (len == 0)
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{
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acb_zero(res);
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}
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else if (len == 1)
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{
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acb_set_si(res, v[0]);
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}
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else if (len == 2)
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{
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acb_mul_si(res, z, v[1], prec);
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acb_add_si(res, res, v[0], prec);
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}
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return;
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}
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m = n_sqrt(len) + 1;
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zk = _acb_vec_init(m + 1);
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_acb_vec_set_powers(zk, z, m + 1, prec);
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acb_init(sq);
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acb_zero(res);
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k = len - 1;
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r = k % m;
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for (; k >= 0; r = m - 1)
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{
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acb_zero(sq);
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for (; r >= 0; r--, k--)
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acb_addmul_si(sq, zk + r, v[k], prec);
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acb_mul(res, res, zk + m, prec);
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acb_add(res, res, sq, prec);
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}
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_acb_vec_clear(zk, m + 1);
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acb_clear(sq);
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}
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