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/*
Copyright (C) 2013-2014 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 "arb.h"
#define TRIM_PADDING 16
void
arb_trim(arb_t y, const arb_t x)
{
if (mag_is_zero(arb_radref(x)) || arf_is_special(arb_midref(x)))
{
arb_set(y, x);
}
else if (mag_is_special(arb_radref(x)))
{
/* midpoint must be finite, so set to 0 +/- inf */
arb_zero_pm_inf(y);
}
else
{
slong bits, accuracy;
bits = arb_bits(x);
accuracy = arb_rel_accuracy_bits(x);
if (accuracy < -TRIM_PADDING)
{
mag_t t;
/* set to 0 +/- r */
mag_init(t);
arf_get_mag(t, arb_midref(x));
mag_add(arb_radref(y), t, arb_radref(x));
mag_clear(t);
arf_zero(arb_midref(y));
}
else if (accuracy < bits - TRIM_PADDING)
{
arb_set_round(y, x, FLINT_MAX(0, accuracy) + TRIM_PADDING);
}
else
{
arb_set(y, x);
}
}
}