mirror of
https://github.com/vale981/arb
synced 2025-03-05 09:21:38 -05:00
124 lines
2.9 KiB
C
124 lines
2.9 KiB
C
/*
|
|
Copyright (C) 2011 William Hart
|
|
Copyright (C) 2012 Fredrik Johansson
|
|
|
|
This file is part of Arb.
|
|
|
|
Arb 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 <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "acb_poly.h"
|
|
|
|
/* TODO: tighten this code */
|
|
|
|
void
|
|
_acb_poly_div(acb_ptr Q,
|
|
acb_srcptr A, slong lenA,
|
|
acb_srcptr B, slong lenB, slong prec)
|
|
{
|
|
slong lenQ, lenB2;
|
|
acb_ptr Arev, Brev;
|
|
|
|
lenQ = lenA - lenB + 1;
|
|
|
|
Arev = _acb_vec_init(2 * lenQ);
|
|
Brev = Arev + lenQ;
|
|
|
|
_acb_poly_reverse(Arev, A + (lenA - lenQ), lenQ, lenQ);
|
|
|
|
if (lenB >= lenQ)
|
|
{
|
|
_acb_poly_reverse(Brev, B + (lenB - lenQ), lenQ, lenQ);
|
|
lenB2 = lenQ;
|
|
}
|
|
else
|
|
{
|
|
_acb_poly_reverse(Brev, B, lenB, lenB);
|
|
lenB2 = lenB;
|
|
}
|
|
|
|
_acb_poly_div_series(Q, Arev, lenQ, Brev, lenB2, lenQ, prec);
|
|
_acb_poly_reverse(Q, Q, lenQ, lenQ);
|
|
|
|
_acb_vec_clear(Arev, 2 * lenQ);
|
|
}
|
|
|
|
void _acb_poly_divrem(acb_ptr Q, acb_ptr R,
|
|
acb_srcptr A, slong lenA,
|
|
acb_srcptr B, slong lenB, slong prec)
|
|
{
|
|
const slong lenQ = lenA - lenB + 1;
|
|
_acb_poly_div(Q, A, lenA, B, lenB, prec);
|
|
|
|
if (lenB > 1)
|
|
{
|
|
if (lenQ >= lenB - 1)
|
|
_acb_poly_mullow(R, Q, lenQ, B, lenB - 1, lenB - 1, prec);
|
|
else
|
|
_acb_poly_mullow(R, B, lenB - 1, Q, lenQ, lenB - 1, prec);
|
|
_acb_vec_sub(R, A, R, lenB - 1, prec);
|
|
}
|
|
}
|
|
|
|
void _acb_poly_rem(acb_ptr R,
|
|
acb_srcptr A, slong lenA,
|
|
acb_srcptr B, slong lenB, slong prec)
|
|
{
|
|
const slong lenQ = lenA - lenB + 1;
|
|
acb_ptr Q = _acb_vec_init(lenQ);
|
|
_acb_poly_divrem(Q, R, A, lenA, B, lenB, prec);
|
|
_acb_vec_clear(Q, lenQ);
|
|
}
|
|
|
|
int acb_poly_divrem(acb_poly_t Q, acb_poly_t R,
|
|
const acb_poly_t A, const acb_poly_t B, slong prec)
|
|
{
|
|
const slong lenA = A->length, lenB = B->length;
|
|
|
|
if (lenB == 0 || acb_contains_zero(B->coeffs + lenB - 1))
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
if (lenA < lenB)
|
|
{
|
|
acb_poly_set(R, A);
|
|
acb_poly_zero(Q);
|
|
return 1;
|
|
}
|
|
|
|
if (Q == A || Q == B)
|
|
{
|
|
acb_poly_t T;
|
|
acb_poly_init(T);
|
|
acb_poly_divrem(T, R, A, B, prec);
|
|
acb_poly_swap(Q, T);
|
|
acb_poly_clear(T);
|
|
return 1;
|
|
}
|
|
|
|
if (R == A || R == B)
|
|
{
|
|
acb_poly_t U;
|
|
acb_poly_init(U);
|
|
acb_poly_divrem(Q, U, A, B, prec);
|
|
acb_poly_swap(R, U);
|
|
acb_poly_clear(U);
|
|
return 1;
|
|
}
|
|
|
|
acb_poly_fit_length(Q, lenA - lenB + 1);
|
|
acb_poly_fit_length(R, lenB - 1);
|
|
|
|
_acb_poly_divrem(Q->coeffs, R->coeffs, A->coeffs, lenA,
|
|
B->coeffs, lenB, prec);
|
|
|
|
_acb_poly_set_length(Q, lenA - lenB + 1);
|
|
_acb_poly_set_length(R, lenB - 1);
|
|
_acb_poly_normalise(R);
|
|
|
|
return 1;
|
|
}
|