124 lines
3.3 KiB
C
124 lines
3.3 KiB
C
/*=============================================================================
|
|
|
|
This file is part of FLINT.
|
|
|
|
FLINT 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.
|
|
|
|
FLINT 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 FLINT; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
=============================================================================*/
|
|
/******************************************************************************
|
|
|
|
Copyright (C) 2013 William Hart
|
|
|
|
******************************************************************************/
|
|
|
|
#include <gmp.h>
|
|
#include "flint.h"
|
|
#include "fmpz.h"
|
|
#include "fmpz_poly.h"
|
|
#include "fmpq_poly.h"
|
|
|
|
void _fmpq_poly_rem_powers_precomp(fmpz * A, fmpz_t denA, slong m,
|
|
const fmpz * B, const fmpz_t denB, slong n,
|
|
fmpq_poly_struct * const powers)
|
|
{
|
|
slong i;
|
|
fmpq_poly_t prod;
|
|
fmpz_t den;
|
|
|
|
if (m >= 2*n) /* TODO: make this case use the precomputed squares */
|
|
{
|
|
fmpz * R = _fmpz_vec_init(m);
|
|
fmpz_init(den);
|
|
|
|
_fmpz_vec_set(R, A, m);
|
|
fmpz_set(den, denA);
|
|
|
|
_fmpq_poly_rem(A, denA, R, den, m, B, denB, n, NULL);
|
|
|
|
_fmpz_vec_clear(R, m);
|
|
fmpz_clear(den);
|
|
|
|
return;
|
|
}
|
|
|
|
if (m < n)
|
|
return;
|
|
|
|
fmpz_init(den);
|
|
|
|
fmpq_poly_init2(prod, n - 1);
|
|
fmpz_set(den, denA);
|
|
|
|
for (i = n - 1; i < m; i++)
|
|
{
|
|
_fmpz_vec_scalar_mul_fmpz(fmpq_poly_numref(prod),
|
|
fmpq_poly_numref(powers + i), powers[i].length, A + i);
|
|
fmpz_mul(fmpq_poly_denref(prod), fmpq_poly_denref(powers + i), den);
|
|
_fmpq_poly_add_can(A, denA, A, denA, n - 1, fmpq_poly_numref(prod),
|
|
fmpq_poly_denref(prod), powers[i].length, 0);
|
|
}
|
|
|
|
fmpq_poly_clear(prod);
|
|
fmpz_clear(den);
|
|
}
|
|
|
|
void
|
|
fmpq_poly_rem_powers_precomp(fmpq_poly_t R, const fmpq_poly_t A,
|
|
const fmpq_poly_t B, const fmpq_poly_powers_precomp_t B_inv)
|
|
{
|
|
fmpq_poly_t tR;
|
|
fmpz * r, * d;
|
|
slong len1 = A->length, len2 = B->length;
|
|
|
|
if (len1 < len2)
|
|
{
|
|
fmpq_poly_set(R, A);
|
|
return;
|
|
}
|
|
|
|
if (R == B)
|
|
{
|
|
fmpq_poly_init2(tR, len1);
|
|
r = fmpq_poly_numref(tR);
|
|
d = fmpq_poly_denref(tR);
|
|
}
|
|
else
|
|
{
|
|
fmpq_poly_fit_length(R, len1);
|
|
r = fmpq_poly_numref(R);
|
|
d = fmpq_poly_denref(R);
|
|
}
|
|
|
|
if (R == B || R != A)
|
|
{
|
|
_fmpz_vec_set(r, fmpq_poly_numref(A), len1);
|
|
fmpz_set(d, fmpq_poly_denref(A));
|
|
}
|
|
|
|
_fmpq_poly_rem_powers_precomp(r, d, len1, fmpq_poly_numref(B),
|
|
fmpq_poly_denref(B), len2, B_inv->powers);
|
|
|
|
if (R == B)
|
|
{
|
|
_fmpq_poly_set_length(tR, len2 - 1);
|
|
fmpq_poly_swap(tR, R);
|
|
fmpq_poly_clear(tR);
|
|
}
|
|
else
|
|
_fmpq_poly_set_length(R, len2 - 1);
|
|
|
|
_fmpq_poly_normalise(R);
|
|
}
|