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/*
Copyright (C) 2011 William Hart
Copyright (C) 2012 Fredrik Johansson
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_poly.h"
void
_acb_poly_div_root(acb_ptr Q, acb_t R, acb_srcptr A,
slong len, const acb_t c, slong prec)
{
acb_t r, t;
slong i;
if (len < 2)
{
acb_zero(R);
return;
}
acb_init(r);
acb_init(t);
acb_set(t, A + len - 2);
acb_set(Q + len - 2, A + len - 1);
acb_set(r, Q + len - 2);
/* TODO: avoid the extra assignments (but still support aliasing) */
for (i = len - 2; i > 0; i--)
{
acb_mul(r, r, c, prec);
acb_add(r, r, t, prec);
acb_set(t, A + i - 1);
acb_set(Q + i - 1, r);
}
acb_mul(r, r, c, prec);
acb_add(R, r, t, prec);
acb_clear(r);
acb_clear(t);
}