mirror of
https://github.com/vale981/arb
synced 2025-03-05 09:21:38 -05:00
81 lines
1.8 KiB
C
81 lines
1.8 KiB
C
/*
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Copyright (C) 2012 Fredrik Johansson
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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 "fmpr.h"
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/* TODO: correct rounding with negative b */
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void
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fmpr_pow_sloppy_fmpz(fmpr_t y, const fmpr_t b, const fmpz_t e,
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slong prec, fmpr_rnd_t rnd)
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{
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slong i, wp, bits;
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if (fmpz_is_zero(e))
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{
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fmpr_set_ui(y, UWORD(1));
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return;
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}
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if (fmpz_sgn(e) < 0)
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{
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fmpz_t f;
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fmpz_init(f);
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fmpz_neg(f, e);
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fmpr_pow_sloppy_fmpz(y, b, f, prec + 2,
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(rnd == FMPR_RND_FLOOR || rnd == FMPR_RND_DOWN)
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? FMPR_RND_UP : FMPR_RND_DOWN);
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fmpr_ui_div(y, UWORD(1), y, prec, rnd);
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fmpz_clear(f);
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return;
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}
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if (y == b)
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{
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fmpr_t t;
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fmpr_init(t);
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fmpr_set(t, b);
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fmpr_pow_sloppy_fmpz(y, t, e, prec, rnd);
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fmpr_clear(t);
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return;
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}
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fmpr_set(y, b);
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bits = fmpz_bits(e);
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wp = FMPR_PREC_ADD(prec, bits);
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for (i = bits - 2; i >= 0; i--)
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{
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fmpr_mul(y, y, y, wp, rnd);
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if (fmpz_tstbit(e, i))
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fmpr_mul(y, y, b, wp, rnd);
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}
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}
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void
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fmpr_pow_sloppy_ui(fmpr_t y, const fmpr_t b, ulong e, slong prec, fmpr_rnd_t rnd)
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{
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fmpz_t f;
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fmpz_init_set_ui(f, e);
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fmpr_pow_sloppy_fmpz(y, b, f, prec, rnd);
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fmpz_clear(f);
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}
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void
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fmpr_pow_sloppy_si(fmpr_t y, const fmpr_t b, slong e, slong prec, fmpr_rnd_t rnd)
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{
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fmpz_t f;
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fmpz_init(f);
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fmpz_set_si(f, e);
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fmpr_pow_sloppy_fmpz(y, b, f, prec, rnd);
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fmpz_clear(f);
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}
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