arb/arf/test/t-is_int_2exp_si.c

/*=============================================================================

    This file is part of ARB.

    ARB 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.

    ARB 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 ARB; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

=============================================================================*/
/******************************************************************************

    Copyright (C) 2016 Fredrik Johansson

******************************************************************************/

#include "arf.h"

int main()
{
    slong iter;
    flint_rand_t state;

    flint_printf("is_int_2exp_si....");
    fflush(stdout);

    flint_randinit(state);

    for (iter = 0; iter < 10000 * arb_test_multiplier(); iter++)
    {
        arf_t x, y;
        fmpz_t t;
        slong e;
        int res1, res2;

        arf_init(x);
        arf_init(y);
        fmpz_init(t);

        arf_randtest_special(x, state, 2000, 100);
        e = n_randtest(state);
        arf_mul_2exp_si(y, x, e);

        res1 = arf_is_int(x);
        res2 = arf_is_int_2exp_si(y, e);

        if (res1 != res2)
        {
            flint_printf("FAIL! (1)\n");
            flint_printf("x = "); arf_print(x); flint_printf("\n\n");
            flint_printf("y = "); arf_print(y); flint_printf("\n\n");
            flint_printf("res1 = %d, res2 = %d\n\n", res1, res2);
            abort();
        }

        if (res1)
        {
            if (n_randint(state, 2))
                arf_floor(y, x);
            else
                arf_ceil(y, x);

            if (!arf_equal(x, y) || !arf_is_finite(x))
            {
                flint_printf("FAIL! (2)\n");
                flint_printf("x = "); arf_print(x); flint_printf("\n\n");
                flint_printf("y = "); arf_print(y); flint_printf("\n\n");
                flint_printf("res1 = %d\n\n", res1);
                abort();
            }
        }

        if (arf_is_finite(x) && !arf_is_zero(x))
        {
            arf_bot(t, x);
            fmpz_neg(t, t);
            arf_mul_2exp_fmpz(x, x, t);
            res1 = arf_is_int(x);
            arf_mul_2exp_si(y, x, -1);
            res2 = arf_is_int(y);

            if (!arf_is_int(x) || arf_is_int(y))
            {
                flint_printf("FAIL! (3)\n");
                flint_printf("x = "); arf_print(x); flint_printf("\n\n");
                flint_printf("y = "); arf_print(y); flint_printf("\n\n");
                flint_printf("res1 = %d, res2 = %d\n\n", res1, res2);
                abort();
            }
        }

        arf_clear(x);
        arf_clear(y);
        fmpz_clear(t);
    }

    flint_randclear(state);
    flint_cleanup();
    flint_printf("PASS\n");
    return EXIT_SUCCESS;
}