100 lines
2.7 KiB
C
100 lines
2.7 KiB
C
/*=============================================================================
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This file is part of FLINT.
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FLINT is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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FLINT is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with FLINT; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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=============================================================================*/
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/******************************************************************************
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Copyright (C) 2010 Sebastian Pancratz
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******************************************************************************/
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#include <stdlib.h>
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#include <gmp.h>
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#include "flint.h"
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#include "fmpz.h"
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#include "fmpz_vec.h"
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#include "fmpq_poly.h"
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void _fmpq_poly_scalar_div_si(fmpz * rpoly, fmpz_t rden, const fmpz * poly,
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const fmpz_t den, slong len, slong c)
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{
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if (c == 1)
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{
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if (rpoly != poly)
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{
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_fmpz_vec_set(rpoly, poly, len);
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fmpz_set(rden, den);
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}
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}
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else if (c == -1)
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{
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_fmpz_vec_neg(rpoly, poly, len);
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fmpz_set(rden, den);
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}
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else
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{
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fmpz_t d, f;
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fmpz_init(d);
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fmpz_init(f);
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fmpz_set_si(f, c);
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_fmpz_vec_content(d, poly, len);
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fmpz_gcd(d, d, f);
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if (c > 0)
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{
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_fmpz_vec_scalar_divexact_fmpz(rpoly, poly, len, d);
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fmpz_mul_si(rden, den, c / fmpz_get_si(d));
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}
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else
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{
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ulong q = (- (ulong) c) / fmpz_get_ui(d);
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fmpz_neg(d, d);
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_fmpz_vec_scalar_divexact_fmpz(rpoly, poly, len, d);
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fmpz_mul_ui(rden, den, q);
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}
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fmpz_clear(d);
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fmpz_clear(f);
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}
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}
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void fmpq_poly_scalar_div_si(fmpq_poly_t rop, const fmpq_poly_t op, slong c)
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{
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if (c == WORD(0))
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{
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flint_printf("Exception (fmpq_poly_scalar_div_si). Division by zero.\n");
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abort();
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}
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if (fmpq_poly_is_zero(op))
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{
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fmpq_poly_zero(rop);
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return;
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}
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fmpq_poly_fit_length(rop, op->length);
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_fmpq_poly_set_length(rop, op->length);
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_fmpq_poly_scalar_div_si(rop->coeffs, rop->den,
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op->coeffs, op->den, op->length, c);
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}
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