Пример #1
0
void
_acb_poly_zeta_cpx_series(acb_ptr z, const acb_t s, const acb_t a, int deflate, long d, long prec)
{
    ulong M, N;
    long i;
    arf_t bound;
    arb_ptr vb;

    if (d < 1)
        return;

    if (!acb_is_finite(s) || !acb_is_finite(a))
    {
        _acb_vec_indeterminate(z, d);
        return;
    }

    arf_init(bound);
    vb = _arb_vec_init(d);

    _acb_poly_zeta_em_choose_param(bound, &N, &M, s, a, FLINT_MIN(d, 2), prec, MAG_BITS);
    _acb_poly_zeta_em_bound(vb, s, a, N, M, d, MAG_BITS);

    _acb_poly_zeta_em_sum(z, s, a, deflate, N, M, d, prec);

    for (i = 0; i < d; i++)
    {
        arb_get_abs_ubound_arf(bound, vb + i, MAG_BITS);
        arb_add_error_arf(acb_realref(z + i), bound);
        arb_add_error_arf(acb_imagref(z + i), bound);
    }

    arf_clear(bound);
    _arb_vec_clear(vb, d);
}
Пример #2
0
void
partitions_fmpz_fmpz_hrr(fmpz_t p, const fmpz_t n, int use_doubles)
{
    arb_t x;
    arf_t bound;
    slong N;

    arb_init(x);
    arf_init(bound);

    N = partitions_hrr_needed_terms(fmpz_get_d(n));

    if (fmpz_cmp_ui(n, 4e8) >= 0 && flint_get_num_threads() > 1)
    {
        hrr_sum_threaded(x, n, N, use_doubles);
    }
    else
    {
        partitions_hrr_sum_arb(x, n, 1, N, use_doubles);
    }

    partitions_rademacher_bound(bound, n, N);
    arb_add_error_arf(x, bound);

    if (!arb_get_unique_fmpz(p, x))
    {
        flint_printf("not unique!\n");
        arb_printd(x, 50);
        flint_printf("\n");
        abort();
    }

    arb_clear(x);
    arf_clear(bound);
}
Пример #3
0
int
_arb_poly_newton_step(arb_t xnew, arb_srcptr poly, long len,
    const arb_t x,
    const arb_t convergence_interval,
    const arf_t convergence_factor, long prec)
{
    arf_t err;
    arb_t t, u, v;
    int result;

    arf_init(err);
    arb_init(t);
    arb_init(u);
    arb_init(v);

    arf_set_mag(err, arb_radref(x));
    arf_mul(err, err, err, MAG_BITS, ARF_RND_UP);
    arf_mul(err, err, convergence_factor, MAG_BITS, ARF_RND_UP);

    arf_set(arb_midref(t), arb_midref(x));
    mag_zero(arb_radref(t));

    _arb_poly_evaluate2(u, v, poly, len, t, prec);

    arb_div(u, u, v, prec);
    arb_sub(u, t, u, prec);

    arb_add_error_arf(u, err);

    if (arb_contains(convergence_interval, u) &&
        (mag_cmp(arb_radref(u), arb_radref(x)) < 0))
    {
        arb_swap(xnew, u);
        result = 1;
    }
    else
    {
        arb_set(xnew, x);
        result = 0;
    }

    arb_clear(t);
    arb_clear(u);
    arb_clear(v);
    arf_clear(err);

    return result;
}
Пример #4
0
int main()
{
    long iter;
    flint_rand_t state;

    printf("add_error....");
    fflush(stdout);

    flint_randinit(state);

    for (iter = 0; iter < 10000; iter++)
    {
        arb_t a, b, c;
        arf_t m, r;

        arb_init(a);
        arb_init(b);
        arb_init(c);
        arf_init(m);
        arf_init(r);

        arb_randtest_special(a, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(b, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(c, state, 1 + n_randint(state, 2000), 10);
        arf_randtest_special(m, state, 1 + n_randint(state, 2000), 10);
        arf_randtest_special(r, state, 1 + n_randint(state, 2000), 10);

        /* c = a plus error bounds */
        arb_set(c, a);
        arf_set(arb_midref(b), m);
        arf_get_mag(arb_radref(b), r);
        arb_add_error(c, b);

        /* b = a + random point */
        arb_set(b, a);

        if (n_randint(state, 2))
            arf_add(arb_midref(b), arb_midref(b), m, ARF_PREC_EXACT, ARF_RND_DOWN);
        else
            arf_sub(arb_midref(b), arb_midref(b), m, ARF_PREC_EXACT, ARF_RND_DOWN);

        if (n_randint(state, 2))
            arf_add(arb_midref(b), arb_midref(b), r, ARF_PREC_EXACT, ARF_RND_DOWN);
        else
            arf_sub(arb_midref(b), arb_midref(b), r, ARF_PREC_EXACT, ARF_RND_DOWN);

        /* should this be done differently? */
        if (arf_is_nan(arb_midref(b)))
            arf_zero(arb_midref(b));

        if (!arb_contains(c, b))
        {
            printf("FAIL (arb_add_error)\n\n");
            printf("a = "); arb_printn(a, 50, 0); printf("\n\n");
            printf("b = "); arb_printn(b, 50, 0); printf("\n\n");
            printf("c = "); arb_printn(c, 50, 0); printf("\n\n");
            abort();
        }

        arb_clear(a);
        arb_clear(b);
        arb_clear(c);
        arf_clear(m);
        arf_clear(r);
    }

    for (iter = 0; iter < 10000; iter++)
    {
        arb_t a, b, c;
        arf_t m;

        arb_init(a);
        arb_init(b);
        arb_init(c);
        arf_init(m);

        arb_randtest_special(a, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(b, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(c, state, 1 + n_randint(state, 2000), 10);
        arf_randtest_special(m, state, 1 + n_randint(state, 2000), 10);

        /* c = a plus error bounds */
        arb_set(c, a);
        arb_add_error_arf(c, m);

        /* b = a + random point */
        arb_set(b, a);

        if (n_randint(state, 2))
            arf_add(arb_midref(b), arb_midref(b), m, ARF_PREC_EXACT, ARF_RND_DOWN);
        else
            arf_sub(arb_midref(b), arb_midref(b), m, ARF_PREC_EXACT, ARF_RND_DOWN);

        /* should this be done differently? */
        if (arf_is_nan(arb_midref(b)))
            arf_zero(arb_midref(b));

        if (!arb_contains(c, b))
        {
            printf("FAIL (arb_add_error_arf)\n\n");
            printf("a = "); arb_printn(a, 50, 0); printf("\n\n");
            printf("b = "); arb_printn(b, 50, 0); printf("\n\n");
            printf("c = "); arb_printn(c, 50, 0); printf("\n\n");
            abort();
        }

        arb_clear(a);
        arb_clear(b);
        arb_clear(c);
        arf_clear(m);
    }

    for (iter = 0; iter < 10000; iter++)
    {
        arb_t a, b, c;
        arf_t t;
        mag_t r;

        arb_init(a);
        arb_init(b);
        arb_init(c);
        mag_init(r);
        arf_init(t);

        arb_randtest_special(a, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(b, state, 1 + n_randint(state, 2000), 10);
        mag_randtest(r, state, 10);

        /* c = a plus error bounds */
        arb_set(c, a);
        arb_add_error_mag(c, r);

        /* b = a + random point */
        arb_set(b, a);
        arf_set_mag(t, r);
        if (n_randint(state, 2))
            arf_add(arb_midref(b), arb_midref(b), t, ARF_PREC_EXACT, ARF_RND_DOWN);
        else
            arf_sub(arb_midref(b), arb_midref(b), t, ARF_PREC_EXACT, ARF_RND_DOWN);

        /* should this be done differently? */
        if (arf_is_nan(arb_midref(b)))
            arf_zero(arb_midref(b));

        if (!arb_contains(c, b))
        {
            printf("FAIL (arb_add_error_mag)\n\n");
            printf("a = "); arb_printn(a, 50, 0); printf("\n\n");
            printf("b = "); arb_printn(b, 50, 0); printf("\n\n");
            printf("c = "); arb_printn(c, 50, 0); printf("\n\n");
            abort();
        }

        arb_clear(a);
        arb_clear(b);
        arb_clear(c);
        mag_clear(r);
        arf_clear(t);
    }

    for (iter = 0; iter < 10000; iter++)
    {
        arb_t a, b, c;
        arf_t t;
        long e;

        arb_init(a);
        arb_init(b);
        arb_init(c);
        arf_init(t);

        arb_randtest_special(a, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(b, state, 1 + n_randint(state, 2000), 10);
        e = n_randint(state, 10) - 10;

        /* c = a plus error bounds */
        arb_set(c, a);
        arb_add_error_2exp_si(c, e);

        /* b = a + random point */
        arb_set(b, a);
        arf_one(t);
        arf_mul_2exp_si(t, t, e);
        if (n_randint(state, 2))
            arf_add(arb_midref(b), arb_midref(b), t, ARF_PREC_EXACT, ARF_RND_DOWN);
        else
            arf_sub(arb_midref(b), arb_midref(b), t, ARF_PREC_EXACT, ARF_RND_DOWN);

        /* should this be done differently? */
        if (arf_is_nan(arb_midref(b)))
            arf_zero(arb_midref(b));

        if (!arb_contains(c, b))
        {
            printf("FAIL (arb_add_error_2exp_si)\n\n");
            printf("a = "); arb_printn(a, 50, 0); printf("\n\n");
            printf("b = "); arb_printn(b, 50, 0); printf("\n\n");
            printf("c = "); arb_printn(c, 50, 0); printf("\n\n");
            abort();
        }

        arb_clear(a);
        arb_clear(b);
        arb_clear(c);
        arf_clear(t);
    }

    for (iter = 0; iter < 10000; iter++)
    {
        arb_t a, b, c;
        arf_t t;
        fmpz_t e;

        arb_init(a);
        arb_init(b);
        arb_init(c);
        arf_init(t);
        fmpz_init(e);

        arb_randtest_special(a, state, 1 + n_randint(state, 2000), 10);
        arb_randtest_special(b, state, 1 + n_randint(state, 2000), 10);
        fmpz_randtest(e, state, 10);

        /* c = a plus error bounds */
        arb_set(c, a);
        arb_add_error_2exp_fmpz(c, e);

        /* b = a + random point */
        arb_set(b, a);
        arf_one(t);
        arf_mul_2exp_fmpz(t, t, e);
        if (n_randint(state, 2))
            arf_add(arb_midref(b), arb_midref(b), t, ARF_PREC_EXACT, ARF_RND_DOWN);
        else
            arf_sub(arb_midref(b), arb_midref(b), t, ARF_PREC_EXACT, ARF_RND_DOWN);

        /* should this be done differently? */
        if (arf_is_nan(arb_midref(b)))
            arf_zero(arb_midref(b));

        if (!arb_contains(c, b))
        {
            printf("FAIL (arb_add_error_2exp_fmpz)\n\n");
            printf("a = "); arb_printn(a, 50, 0); printf("\n\n");
            printf("b = "); arb_printn(b, 50, 0); printf("\n\n");
            printf("c = "); arb_printn(c, 50, 0); printf("\n\n");
            abort();
        }

        arb_clear(a);
        arb_clear(b);
        arb_clear(c);
        arf_clear(t);
        fmpz_clear(e);
    }

    flint_randclear(state);
    flint_cleanup();
    printf("PASS\n");
    return EXIT_SUCCESS;
}
int
acb_calc_integrate_taylor(acb_t res,
    acb_calc_func_t func, void * param,
    const acb_t a, const acb_t b,
    const arf_t inner_radius,
    const arf_t outer_radius,
    long accuracy_goal, long prec)
{
    long num_steps, step, N, bp;
    int result;

    acb_t delta, m, x, y1, y2, sum;
    acb_ptr taylor_poly;
    arf_t err;

    acb_init(delta);
    acb_init(m);
    acb_init(x);
    acb_init(y1);
    acb_init(y2);
    acb_init(sum);
    arf_init(err);

    acb_sub(delta, b, a, prec);

    /* precision used for bounds calculations */
    bp = MAG_BITS;

    /* compute the number of steps */
    {
        arf_t t;
        arf_init(t);
        acb_get_abs_ubound_arf(t, delta, bp);
        arf_div(t, t, inner_radius, bp, ARF_RND_UP);
        arf_mul_2exp_si(t, t, -1);
        num_steps = (long) (arf_get_d(t, ARF_RND_UP) + 1.0);
        /* make sure it's not something absurd */
        num_steps = FLINT_MIN(num_steps, 10 * prec);
        num_steps = FLINT_MAX(num_steps, 1);
        arf_clear(t);
    }

    result = ARB_CALC_SUCCESS;

    acb_zero(sum);

    for (step = 0; step < num_steps; step++)
    {
        /* midpoint of subinterval */
        acb_mul_ui(m, delta, 2 * step + 1, prec);
        acb_div_ui(m, m, 2 * num_steps, prec);
        acb_add(m, m, a, prec);

        if (arb_calc_verbose)
        {
            printf("integration point %ld/%ld: ", 2 * step + 1, 2 * num_steps);
            acb_printd(m, 15); printf("\n");
        }

        /* evaluate at +/- x */
        /* TODO: exactify m, and include error in x? */
        acb_div_ui(x, delta, 2 * num_steps, prec);

        /* compute bounds and number of terms to use */
        {
            arb_t cbound, xbound, rbound;
            arf_t C, D, R, X, T;
            double DD, TT, NN;

            arb_init(cbound);
            arb_init(xbound);
            arb_init(rbound);
            arf_init(C);
            arf_init(D);
            arf_init(R);
            arf_init(X);
            arf_init(T);

            /* R is the outer radius */
            arf_set(R, outer_radius);

            /* X = upper bound for |x| */
            acb_get_abs_ubound_arf(X, x, bp);
            arb_set_arf(xbound, X);

            /* Compute C(m,R). Important subtlety: due to rounding when
               computing m, we will in general be farther than R away from
               the integration path. But since acb_calc_cauchy_bound
               actually integrates over the area traced by a complex
               interval, it will catch any extra singularities (giving
               an infinite bound). */
            arb_set_arf(rbound, outer_radius);
            acb_calc_cauchy_bound(cbound, func, param, m, rbound, 8, bp);
            arf_set_mag(C, arb_radref(cbound));
            arf_add(C, arb_midref(cbound), C, bp, ARF_RND_UP);

            /* Sanity check: we need C < inf and R > X */
            if (arf_is_finite(C) && arf_cmp(R, X) > 0)
            {
                /* Compute upper bound for D = C * R * X / (R - X) */
                arf_mul(D, C, R, bp, ARF_RND_UP);
                arf_mul(D, D, X, bp, ARF_RND_UP);
                arf_sub(T, R, X, bp, ARF_RND_DOWN);
                arf_div(D, D, T, bp, ARF_RND_UP);

                /* Compute upper bound for T = (X / R) */
                arf_div(T, X, R, bp, ARF_RND_UP);

                /* Choose N */
                /* TODO: use arf arithmetic to avoid overflow */
                /* TODO: use relative accuracy (look at |f(m)|?) */
                DD = arf_get_d(D, ARF_RND_UP);
                TT = arf_get_d(T, ARF_RND_UP);
                NN = -(accuracy_goal * 0.69314718055994530942 + log(DD)) / log(TT);
                N = NN + 0.5;
                N = FLINT_MIN(N, 100 * prec);
                N = FLINT_MAX(N, 1);

                /* Tail bound: D / (N + 1) * T^N */
                {
                    mag_t TT;
                    mag_init(TT);
                    arf_get_mag(TT, T);
                    mag_pow_ui(TT, TT, N);
                    arf_set_mag(T, TT);
                    mag_clear(TT);
                }
                arf_mul(D, D, T, bp, ARF_RND_UP);
                arf_div_ui(err, D, N + 1, bp, ARF_RND_UP);
            }
            else
            {
                N = 1;
                arf_pos_inf(err);
                result = ARB_CALC_NO_CONVERGENCE;
            }

            if (arb_calc_verbose)
            {
                printf("N = %ld; bound: ", N); arf_printd(err, 15); printf("\n");
                printf("R: "); arf_printd(R, 15); printf("\n");
                printf("C: "); arf_printd(C, 15); printf("\n");
                printf("X: "); arf_printd(X, 15); printf("\n");
            }

            arb_clear(cbound);
            arb_clear(xbound);
            arb_clear(rbound);
            arf_clear(C);
            arf_clear(D);
            arf_clear(R);
            arf_clear(X);
            arf_clear(T);
        }

        /* evaluate Taylor polynomial */
        taylor_poly = _acb_vec_init(N + 1);
        func(taylor_poly, m, param, N, prec);
        _acb_poly_integral(taylor_poly, taylor_poly, N + 1, prec);
        _acb_poly_evaluate(y2, taylor_poly, N + 1, x, prec);
        acb_neg(x, x);
        _acb_poly_evaluate(y1, taylor_poly, N + 1, x, prec);
        acb_neg(x, x);

        /* add truncation error */
        arb_add_error_arf(acb_realref(y1), err);
        arb_add_error_arf(acb_imagref(y1), err);
        arb_add_error_arf(acb_realref(y2), err);
        arb_add_error_arf(acb_imagref(y2), err);

        acb_add(sum, sum, y2, prec);
        acb_sub(sum, sum, y1, prec);

        if (arb_calc_verbose)
        {
            printf("values:  ");
            acb_printd(y1, 15); printf("  ");
            acb_printd(y2, 15); printf("\n");
        }

        _acb_vec_clear(taylor_poly, N + 1);

        if (result == ARB_CALC_NO_CONVERGENCE)
            break;
    }

    acb_set(res, sum);

    acb_clear(delta);
    acb_clear(m);
    acb_clear(x);
    acb_clear(y1);
    acb_clear(y2);
    acb_clear(sum);
    arf_clear(err);

    return result;
}