static void
acb_approx_mul(acb_t res, const acb_t x, const acb_t y, slong prec)
{
    arf_complex_mul(arb_midref(acb_realref(res)), arb_midref(acb_imagref(res)),
        arb_midref(acb_realref(x)), arb_midref(acb_imagref(x)), 
        arb_midref(acb_realref(y)), arb_midref(acb_imagref(y)), prec, ARB_RND);
}
Beispiel #2
0
/* Extremely close to the branch point at -1/e, use the series expansion directly. */
int
acb_lambertw_try_near_branch_point(acb_t res, const acb_t z,
    const acb_t ez1, const fmpz_t k, int flags, slong prec)
{
    if (fmpz_is_zero(k) || (fmpz_is_one(k) && arb_is_negative(acb_imagref(z)))
                        || (fmpz_equal_si(k, -1) && arb_is_nonnegative(acb_imagref(z))))
    {
        if (acb_contains_zero(ez1) ||
            (arf_cmpabs_2exp_si(arb_midref(acb_realref(ez1)), -prec / 4.5 - 6) < 0 &&
             arf_cmpabs_2exp_si(arb_midref(acb_imagref(ez1)), -prec / 4.5 - 6) < 0))
        {
            acb_t t;
            acb_init(t);
            acb_mul_2exp_si(t, ez1, 1);
            acb_sqrt(t, t, prec);
            if (!fmpz_is_zero(k))
                acb_neg(t, t);
            acb_lambertw_branchpoint_series(res, t, 1, prec);
            acb_clear(t);
            return 1;
        }
    }

    return 0;
}
Beispiel #3
0
int acb_cmp_pretty(const acb_t a, const acb_t b)
{
    arb_t t, u, v;
    int res;
    arb_init(t);
    arb_init(u);
    arb_init(v);
    arb_abs(u, acb_imagref(a));
    arb_abs(v, acb_imagref(b));
    arb_sub(t, u, v, MAG_BITS);
    res = 0;
    if (arb_contains_zero(t))
    {
        arb_sub(t, acb_realref(a), acb_realref(b), MAG_BITS);
        res = arb_is_positive(t) ? 1 : -1;
    }
    else
    {
        res = arb_is_positive(t) ? 1 : -1;
    }
    arb_clear(t);
    arb_clear(u);
    arb_clear(v);
    return res;
}
void
acb_get_mag(mag_t u, const acb_t z)
{
    if (arb_is_zero(acb_imagref(z)))
    {
        arb_get_mag(u, acb_realref(z));
    }
    else if (arb_is_zero(acb_realref(z)))
    {
        arb_get_mag(u, acb_imagref(z));
    }
    else
    {
        mag_t v;
        mag_init(v);

        arb_get_mag(u, acb_realref(z));
        arb_get_mag(v, acb_imagref(z));

        mag_mul(u, u, u);
        mag_addmul(u, v, v);
        mag_sqrt(u, u);

        mag_clear(v);
    }
}
Beispiel #5
0
static void
acb_set_dddd(acb_t z, double a, double ar, double b, double br)
{
    arf_set_d(arb_midref(acb_realref(z)), a);
    mag_set_d(arb_radref(acb_realref(z)), ar);
    arf_set_d(arb_midref(acb_imagref(z)), b);
    mag_set_d(arb_radref(acb_imagref(z)), br);
}
Beispiel #6
0
Datei: erf.c Projekt: isuruf/arb
void
acb_hypgeom_erf(acb_t res, const acb_t z, slong prec)
{
    double x, y, absz2, logz;
    slong prec2;

    if (!acb_is_finite(z))
    {
        acb_indeterminate(res);
        return;
    }

    if (acb_is_zero(z))
    {
        acb_zero(res);
        return;
    }

    if ((arf_cmpabs_2exp_si(arb_midref(acb_realref(z)), 0) < 0 &&
            arf_cmpabs_2exp_si(arb_midref(acb_imagref(z)), 0) < 0))
    {
        acb_hypgeom_erf_1f1a(res, z, prec);
        return;
    }

    if ((arf_cmpabs_2exp_si(arb_midref(acb_realref(z)), 64) > 0 ||
            arf_cmpabs_2exp_si(arb_midref(acb_imagref(z)), 64) > 0))
    {
        acb_hypgeom_erf_asymp(res, z, prec, prec);
        return;
    }

    x = arf_get_d(arb_midref(acb_realref(z)), ARF_RND_DOWN);
    y = arf_get_d(arb_midref(acb_imagref(z)), ARF_RND_DOWN);

    absz2 = x * x + y * y;
    logz = 0.5 * log(absz2);

    if (logz - absz2 < -(prec + 8) * 0.69314718055994530942)
    {
        /* If the asymptotic term is small, we can
           compute with reduced precision */
        prec2 = FLINT_MIN(prec + 4 + (y*y - x*x - logz) * 1.4426950408889634074, (double) prec);
        prec2 = FLINT_MAX(8, prec2);
        prec2 = FLINT_MIN(prec2, prec);

        acb_hypgeom_erf_asymp(res, z, prec, prec2);
    }
    else if (arf_cmpabs(arb_midref(acb_imagref(z)), arb_midref(acb_realref(z))) > 0)
    {
        acb_hypgeom_erf_1f1a(res, z, prec);
    }
    else
    {
        acb_hypgeom_erf_1f1b(res, z, prec);
    }
}
Beispiel #7
0
void
acb_lambertw_principal_d(acb_t res, const acb_t z)
{
    double za, zb, wa, wb, ewa, ewb, t, u, q, r;
    int k, maxk = 15;

    za = arf_get_d(arb_midref(acb_realref(z)), ARF_RND_DOWN);
    zb = arf_get_d(arb_midref(acb_imagref(z)), ARF_RND_DOWN);

    /* make sure we end up on the right branch */
    if (za < -0.367 && zb > -1e-20 && zb <= 0.0
                  && arf_sgn(arb_midref(acb_imagref(z))) < 0)
        zb = -1e-20;

    wa = za;
    wb = zb;

    if (fabs(wa) > 2.0 || fabs(wb) > 2.0)
    {
        t = atan2(wb, wa);
        wa = 0.5 * log(wa * wa + wb * wb);
        wb = t;
    }
    else if (fabs(wa) > 0.25 || fabs(wb) > 0.25)
    {
        /* We have W(z) ~= -1 + (2(ez+1))^(1/2) near the branch point.
           Changing the exponent to 1/4 gives a much worse local guess
           which however does the job on a larger domain. */
        wa *= 5.43656365691809;
        wb *= 5.43656365691809;
        wa += 2.0;
        t = atan2(wb, wa);
        r = pow(wa * wa + wb * wb, 0.125);
        wa = r * cos(0.25 * t);
        wb = r * sin(0.25 * t);
        wa -= 1.0;
    }

    for (k = 0; k < maxk; k++)
    {
        t = exp(wa);
        ewa = t * cos(wb);
        ewb = t * sin(wb);
        t = (ewa * wa - ewb * wb); q = t + ewa; t -= za;
        u = (ewb * wa + ewa * wb); r = u + ewb; u -= zb;
        ewa = q * t + r * u; ewb = q * u - r * t;
        r = 1.0 / (q * q + r * r);
        ewa *= r; ewb *= r;
        if ((ewa*ewa + ewb*ewb) < (wa*wa + wb*wb) * 1e-12)
            maxk = FLINT_MIN(maxk, k + 2);
        wa -= ewa; wb -= ewb;
    }

    acb_set_d_d(res, wa, wb);
}
Beispiel #8
0
void
acb_hypgeom_erf_propagated_error(mag_t re, mag_t im, const acb_t z)
{
    mag_t x, y;

    mag_init(x);
    mag_init(y);

    /* |exp(-(x+y)^2)| = exp(y^2-x^2) */
    arb_get_mag(y, acb_imagref(z));
    mag_mul(y, y, y);

    arb_get_mag_lower(x, acb_realref(z));
    mag_mul_lower(x, x, x);

    if (mag_cmp(y, x) >= 0)
    {
        mag_sub(re, y, x);
        mag_exp(re, re);
    }
    else
    {
        mag_sub_lower(re, x, y);
        mag_expinv(re, re);
    }

    /* Radius. */
    mag_hypot(x, arb_radref(acb_realref(z)), arb_radref(acb_imagref(z)));
    mag_mul(re, re, x);

    /* 2/sqrt(pi) < 289/256 */
    mag_mul_ui(re, re, 289);
    mag_mul_2exp_si(re, re, -8);

    if (arb_is_zero(acb_imagref(z)))
    {
        /* todo: could bound magnitude even for complex numbers */
        mag_set_ui(y, 2);
        mag_min(re, re, y);

        mag_zero(im);
    }
    else if (arb_is_zero(acb_realref(z)))
    {
        mag_swap(im, re);
        mag_zero(re);
    }
    else
    {
        mag_set(im, re);
    }

    mag_clear(x);
    mag_clear(y);
}
Beispiel #9
0
int main()
{
    flint_printf("spherical_y....");
    fflush(stdout);

    {
        slong i, n, m;
        acb_t z, w, x, y;

        acb_init(z);
        acb_init(w);
        acb_init(x);
        acb_init(y);

        i = 0;

        arb_set_str(acb_realref(x), "0.2", 64);
        arb_set_str(acb_imagref(x), "0.3", 64);
        arb_set_str(acb_realref(y), "0.3", 64);
        arb_set_str(acb_imagref(y), "0.4", 64);

        for (n = -4; n <= 4; n++)
        {
            for (m = -4; m <= 4; m++)
            {
                acb_hypgeom_spherical_y(z, n, m, x, y, 64);

                acb_set_d_d(w, testdata[2 * i], testdata[2 * i + 1]);
                mag_set_d(arb_radref(acb_realref(w)), 1e-13);
                mag_set_d(arb_radref(acb_imagref(w)), 1e-13);

                if (!acb_overlaps(z, w))
                {
                    flint_printf("FAIL: value\n\n");
                    flint_printf("n = %wd, m = %wd\n", n, m);
                    flint_printf("z = "); acb_printd(z, 20); flint_printf("\n\n");
                    flint_printf("w = "); acb_printd(w, 20); flint_printf("\n\n");
                    abort();
                }

                i++;
            }
        }

        acb_clear(z);
        acb_clear(w);
        acb_clear(x);
        acb_clear(y);
    }

    flint_cleanup();
    flint_printf("PASS\n");
    return EXIT_SUCCESS;
}
Beispiel #10
0
void
acb_hypgeom_bessel_jy(acb_t res1, acb_t res2, const acb_t nu, const acb_t z, slong prec)
{
    acb_t jnu, t, u, v;

    acb_init(jnu);
    acb_init(t);
    acb_init(u);
    acb_init(v);

    acb_hypgeom_bessel_j(jnu, nu, z, prec);

    if (acb_is_int(nu))
    {
        int is_real = acb_is_real(nu) && acb_is_real(z)
            && arb_is_positive(acb_realref(z));

        acb_mul_onei(t, z);
        acb_hypgeom_bessel_k(t, nu, t, prec);
        acb_onei(u);
        acb_pow(u, u, nu, prec);
        acb_mul(t, t, u, prec);
        acb_const_pi(u, prec);
        acb_div(t, t, u, prec);
        acb_mul_2exp_si(t, t, 1);
        acb_neg(t, t);

        phase(v, acb_realref(z), acb_imagref(z));
        acb_mul(u, jnu, v, prec);
        acb_mul_onei(u, u);

        acb_sub(res2, t, u, prec);

        if (is_real)
            arb_zero(acb_imagref(res2));
    }
    else
    {
        acb_sin_cos_pi(t, u, nu, prec);
        acb_mul(v, jnu, u, prec);
        acb_neg(u, nu);
        acb_hypgeom_bessel_j(u, u, z, prec);
        acb_sub(v, v, u, prec);
        acb_div(res2, v, t, prec);
    }

    if (res1 != NULL)
        acb_set(res1, jnu);

    acb_clear(jnu);
    acb_clear(t);
    acb_clear(u);
    acb_clear(v);
}
/* note: the tmp variable t should have zero radius */
static void
acb_approx_div(acb_t z, const acb_t x, const acb_t y, acb_t t, slong prec)
{
    arf_set(arb_midref(acb_realref(t)), arb_midref(acb_realref(y)));
    arf_set(arb_midref(acb_imagref(t)), arb_midref(acb_imagref(y)));

    acb_inv(t, t, prec);

    mag_zero(arb_radref(acb_realref(t)));
    mag_zero(arb_radref(acb_imagref(t)));

    acb_approx_mul(z, x, t, prec);
}
Beispiel #12
0
static void
bsplit(arb_poly_t pol, const arb_t sqrtD,
            const slong * qbf, slong a, slong b, slong prec)
{
    if (b - a == 0)
    {
        arb_poly_one(pol);
    }
    else if (b - a == 1)
    {
        acb_t z;
        acb_init(z);

        /* j((-b+sqrt(-D))/(2a)) */
        arb_set_si(acb_realref(z), -FLINT_ABS(qbf[3 * a + 1]));
        arb_set(acb_imagref(z), sqrtD);
        acb_div_si(z, z, 2 * qbf[3 * a], prec);
        acb_modular_j(z, z, prec);

        if (qbf[3 * a + 1] < 0)
        {
            /* (x^2 - 2re(j) x + |j|^2) */
            arb_poly_fit_length(pol, 3);
            arb_mul(pol->coeffs, acb_realref(z), acb_realref(z), prec);
            arb_addmul(pol->coeffs, acb_imagref(z), acb_imagref(z), prec);
            arb_mul_2exp_si(pol->coeffs + 1, acb_realref(z), 1);
            arb_neg(pol->coeffs + 1, pol->coeffs + 1);
            arb_one(pol->coeffs + 2);
            _arb_poly_set_length(pol, 3);
        }
        else
        {
            /* (x-j) */
            arb_poly_fit_length(pol, 2);
            arb_neg(pol->coeffs, acb_realref(z));
            arb_one(pol->coeffs + 1);
            _arb_poly_set_length(pol, 2);
        }

        acb_clear(z);
    }
    else
    {
        arb_poly_t tmp;
        arb_poly_init(tmp);
        bsplit(pol, sqrtD, qbf, a, a + (b - a) / 2, prec);
        bsplit(tmp, sqrtD, qbf, a + (b - a) / 2, b, prec);
        arb_poly_mul(pol, pol, tmp, prec);
        arb_poly_clear(tmp);
    }
}
void
acb_dirichlet_gauss_sum_order2(acb_t res, const dirichlet_group_t G, const dirichlet_char_t chi, slong prec)
{
    if (dirichlet_parity_char(G, chi))
    {
        arb_zero(acb_realref(res));
        arb_sqrt_ui(acb_imagref(res), G->q, prec);
    }
    else
    {
        arb_zero(acb_imagref(res));
        arb_sqrt_ui(acb_realref(res), G->q, prec);
    }
}
Beispiel #14
0
Datei: erf.c Projekt: isuruf/arb
void
acb_hypgeom_erf_asymp(acb_t res, const acb_t z, slong prec, slong prec2)
{
    acb_t a, t, u;

    acb_init(a);
    acb_init(t);
    acb_init(u);

    acb_one(a);
    acb_mul_2exp_si(a, a, -1);
    acb_mul(t, z, z, prec2);

    acb_hypgeom_u_asymp(u, a, a, t, -1, prec2);

    acb_neg(t, t);
    acb_exp(t, t, prec2);
    acb_mul(u, u, t, prec2);

    acb_const_pi(t, prec2);
    acb_sqrt(t, t, prec2);
    acb_mul(t, t, z, prec2);

    acb_div(u, u, t, prec2);

    /* branch cut term: -1 or 1 */
    if (arb_contains_zero(acb_realref(z)))
    {
        arb_zero(acb_imagref(t));
        arf_zero(arb_midref(acb_realref(t)));
        mag_one(arb_radref(acb_realref(t)));
    }
    else
    {
        acb_set_si(t, arf_sgn(arb_midref(acb_realref(z))));
    }

    acb_sub(t, t, u, prec);

    if (arb_is_zero(acb_imagref(z)))
        arb_zero(acb_imagref(t));
    else if (arb_is_zero(acb_realref(z)))
        arb_zero(acb_realref(t));

    acb_set(res, t);

    acb_clear(a);
    acb_clear(t);
    acb_clear(u);
}
Beispiel #15
0
void
acb_log1p(acb_t r, const acb_t z, slong prec)
{
    slong magz, magx, magy;

    if (acb_is_zero(z))
    {
        acb_zero(r);
        return;
    }

    magx = arf_abs_bound_lt_2exp_si(arb_midref(acb_realref(z)));
    magy = arf_abs_bound_lt_2exp_si(arb_midref(acb_imagref(z)));
    magz = FLINT_MAX(magx, magy);

    if (magz < -prec)
    {
        acb_log1p_tiny(r, z, prec);
    }
    else
    {
        if (magz < 0)
            acb_add_ui(r, z, 1, prec + (-magz) + 4);
        else
            acb_add_ui(r, z, 1, prec + 4);

        acb_log(r, r, prec);
    }
}
Beispiel #16
0
int
bessel(acb_ptr out, const acb_t inp, void * params, long order, long prec)
{
    acb_ptr t;
    acb_t z;
    ulong n;

    t = _acb_vec_init(order);
    acb_init(z);

    acb_set(t, inp);
    if (order > 1)
        acb_one(t + 1);

    n = 10;
    arb_set_si(acb_realref(z), 20);
    arb_set_si(acb_imagref(z), 10);

    /* z sin(t) */
    _acb_poly_sin_series(out, t, FLINT_MIN(2, order), order, prec);
    _acb_vec_scalar_mul(out, out, order, z, prec);

    /* t n */
    _acb_vec_scalar_mul_ui(t, t, FLINT_MIN(2, order), n, prec);

    _acb_poly_sub(out, t, FLINT_MIN(2, order), out, order, prec);

    _acb_poly_cos_series(out, out, order, order, prec);

    _acb_vec_clear(t, order);
    acb_clear(z);
    return 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);
}
Beispiel #18
0
void
acb_dirichlet_theta_arb(acb_t res, const dirichlet_group_t G, const dirichlet_char_t chi, const arb_t t, slong prec)
{
    slong len;
    ulong order;
    arb_t xt;
    mag_t e;

    len = acb_dirichlet_theta_length(G->q, t, prec);

    arb_init(xt);
    _acb_dirichlet_theta_argument_at_arb(xt, G->q, t, prec);

    mag_init(e);
    mag_tail_kexpk2_arb(e, xt, len);

    arb_neg(xt, xt);
    arb_exp(xt, xt, prec);

    /* TODO: tune this limit */
    order = dirichlet_order_char(G, chi);
    if (order < 30)
        _acb_dirichlet_theta_arb_smallorder(res, G, chi, xt, len, prec);
    else
        _acb_dirichlet_theta_arb_naive(res, G, chi, xt, len, prec);

    arb_add_error_mag(acb_realref(res), e);
    arb_add_error_mag(acb_imagref(res), e);

    mag_clear(e);

    acb_mul_2exp_si(res, res, 1);
    arb_clear(xt);
}
Beispiel #19
0
void
acb_lambertw_cleared_cut_fix_small(acb_t res, const acb_t z,
    const acb_t ez1, const fmpz_t k, int flags, slong prec)
{
    acb_t zz, zmid, zmide1;
    arf_t eps;

    acb_init(zz);
    acb_init(zmid);
    acb_init(zmide1);
    arf_init(eps);

    arf_mul_2exp_si(eps, arb_midref(acb_realref(z)), -prec);
    acb_set(zz, z);

    if (arf_sgn(arb_midref(acb_realref(zz))) < 0 &&
        (!fmpz_is_zero(k) || arf_sgn(arb_midref(acb_realref(ez1))) < 0) &&
        arf_cmpabs(arb_midref(acb_imagref(zz)), eps) < 0)
    {
        /* now the value must be in [0,2eps] */
        arf_get_mag(arb_radref(acb_imagref(zz)), eps);
        arf_set_mag(arb_midref(acb_imagref(zz)), arb_radref(acb_imagref(zz)));

        if (arf_sgn(arb_midref(acb_imagref(z))) >= 0)
        {
            acb_lambertw_cleared_cut(res, zz, k, flags, prec);
        }
        else
        {
            fmpz_t kk;
            fmpz_init(kk);
            fmpz_neg(kk, k);
            acb_lambertw_cleared_cut(res, zz, kk, flags, prec);
            acb_conj(res, res);
            fmpz_clear(kk);
        }
    }
    else
    {
        acb_lambertw_cleared_cut(res, zz, k, flags, prec);
    }

    acb_clear(zz);
    acb_clear(zmid);
    acb_clear(zmide1);
    arf_clear(eps);
}
Beispiel #20
0
void
acb_hypgeom_m_asymp(acb_t res, const acb_t a, const acb_t b, const acb_t z, int regularized, slong prec)
{
    acb_t t, u, v, c;

    acb_init(t);
    acb_init(u);
    acb_init(v);
    acb_init(c);

    acb_sub(c, b, a, prec);
    acb_neg(v, z);

    acb_hypgeom_u_asymp(t, a, b, z, -1, prec);
    acb_hypgeom_u_asymp(u, c, b, v, -1, prec);

    /* gamma(b-a) */
    acb_rgamma(v, c, prec);
    acb_mul(t, t, v, prec);

    /* z^(a-b) */
    acb_neg(c, c);
    acb_pow(v, z, c, prec);
    acb_mul(u, u, v, prec);

    /* gamma(a) */
    acb_rgamma(v, a, prec);
    acb_mul(u, u, v, prec);

    /* exp(z) */
    acb_exp(v, z, prec);
    acb_mul(u, u, v, prec);

    /* (-z)^(-a) */
    acb_neg(c, a);
    acb_neg(v, z);
    acb_pow(v, v, c, prec);
    acb_mul(t, t, v, prec);

    acb_add(t, t, u, prec);

    if (!regularized)
    {
        acb_gamma(v, b, prec);
        acb_mul(t, t, v, prec);
    }

    if (acb_is_real(a) && acb_is_real(b) && acb_is_real(z))
    {
        arb_zero(acb_imagref(t));
    }

    acb_swap(res, t);

    acb_clear(t);
    acb_clear(u);
    acb_clear(v);
    acb_clear(c);
}
Beispiel #21
0
int
acb_contains_int(const acb_t x)
{
    if (!arb_contains_zero(acb_imagref(x)))
        return 0;

    return arb_contains_int(acb_realref(x));
}
Beispiel #22
0
void
acb_log_sin_pi(acb_t res, const acb_t z, slong prec)
{
    if (!acb_is_finite(z))
    {
        acb_indeterminate(res);
        return;
    }

    if (arb_is_positive(acb_imagref(z)) ||
        (arb_is_zero(acb_imagref(z)) && arb_is_negative(acb_realref(z))))
    {
        acb_log_sin_pi_half(res, z, prec, 1);
    }
    else if (arb_is_negative(acb_imagref(z)) ||
        (arb_is_zero(acb_imagref(z)) && arb_is_positive(acb_realref(z))))
    {
        acb_log_sin_pi_half(res, z, prec, 0);
    }
    else
    {
        acb_t t;
        acb_init(t);
        acb_log_sin_pi_half(t, z, prec, 1);
        acb_log_sin_pi_half(res, z, prec, 0);
        arb_union(acb_realref(res), acb_realref(res), acb_realref(t), prec);
        arb_union(acb_imagref(res), acb_imagref(res), acb_imagref(t), prec);
        acb_clear(t);
    }
}
Beispiel #23
0
static void
_acb_unit_root(acb_t res, ulong order, slong prec)
{
    fmpq_t t;
    fmpq_init(t);
    fmpq_set_si(t, 2, order);
    arb_sin_cos_pi_fmpq(acb_imagref(res), acb_realref(res), t, prec);
    fmpq_clear(t);
}
Beispiel #24
0
/* invalid in (-1,0) */
int
_acb_hypgeom_legendre_q_single_valid(const acb_t z)
{
    arb_t t;
    int ok;

    if (!arb_contains_zero(acb_imagref(z)))
        return 1;

    if (arb_is_positive(acb_imagref(z)))
        return 1;

    arb_init(t);
    arb_one(t);
    arb_neg(t, t);
    ok = arb_lt(acb_realref(z), t);
    arb_clear(t);
    return ok;
}
Beispiel #25
0
Datei: cot.c Projekt: isuruf/arb
void
acb_cot(acb_t r, const acb_t z, slong prec)
{
    if (arb_is_zero(acb_imagref(z)))
    {
        arb_cot(acb_realref(r), acb_realref(z), prec);
        arb_zero(acb_imagref(r));
    }
    else if (arb_is_zero(acb_realref(z)))
    {
        arb_coth(acb_imagref(r), acb_imagref(z), prec);
        arb_neg(acb_imagref(r), acb_imagref(r));
        arb_zero(acb_realref(r));
    }
    else
    {
        acb_t t;
        acb_init(t);

        if (arf_cmpabs_2exp_si(arb_midref(acb_imagref(z)), 0) < 0)
        {
            acb_sin_cos(r, t, z, prec + 4);
            acb_div(r, t, r, prec);
        }
        else
        {
            acb_mul_2exp_si(t, z, 1);

            if (arf_sgn(arb_midref(acb_imagref(z))) > 0)
            {
                acb_mul_onei(t, t);
                acb_exp(t, t, prec + 4);
                acb_sub_ui(r, t, 1, prec + 4);
                acb_div(r, t, r, prec + 4);
                acb_mul_2exp_si(r, r, 1);
                acb_sub_ui(r, r, 1, prec);
                acb_mul_onei(r, r);
            }
            else
            {
                acb_div_onei(t, t);
                acb_exp(t, t, prec + 4);
                acb_sub_ui(r, t, 1, prec + 4);
                acb_div(r, t, r, prec + 4);
                acb_mul_2exp_si(r, r, 1);
                acb_sub_ui(r, r, 1, prec);
                acb_div_onei(r, r);
            }
        }

        acb_clear(t);
    }
}
Beispiel #26
0
slong
_acb_get_mid_mag(const acb_t z)
{
    slong rm, im;

    rm = arf_abs_bound_lt_2exp_si(arb_midref(acb_realref(z)));
    im = arf_abs_bound_lt_2exp_si(arb_midref(acb_imagref(z)));

    return FLINT_MAX(rm, im);
}
Beispiel #27
0
int main()
{
    slong iter;
    flint_rand_t state;

    flint_printf("get_mag....");
    fflush(stdout);
    flint_randinit(state);

    for (iter = 0; iter < 10000 * arb_test_multiplier(); iter++)
    {
        acb_t a;
        arf_t m2, x, y, s;
        mag_t m;

        acb_init(a);
        mag_init(m);
        arf_init(m2);
        arf_init(x);
        arf_init(y);
        arf_init(s);

        acb_randtest_special(a, state, 200, 10);
        acb_get_mag(m, a);
        MAG_CHECK_BITS(m)

        /* check m^2 >= x^2 + y^2 */
        arf_set_mag(m2, m);
        arf_mul(m2, m2, m2, ARF_PREC_EXACT, ARF_RND_DOWN);

        arb_get_abs_ubound_arf(x, acb_realref(a), ARF_PREC_EXACT);
        arb_get_abs_ubound_arf(y, acb_imagref(a), ARF_PREC_EXACT);
        arf_sosq(s, x, y, ARF_PREC_EXACT, ARF_RND_DOWN);

        if (arf_cmp(m2, s) < 0)
        {
            flint_printf("FAIL:\n\n");
            flint_printf("a = "); acb_print(a); flint_printf("\n\n");
            flint_printf("m = "); mag_print(m); flint_printf("\n\n");
            flint_abort();
        }

        acb_clear(a);
        mag_clear(m);
        arf_clear(m2);
        arf_clear(x);
        arf_clear(y);
        arf_clear(s);
    }

    flint_randclear(state);
    flint_cleanup();
    flint_printf("PASS\n");
    return EXIT_SUCCESS;
}
Beispiel #28
0
void
acb_lambertw_cleared_cut(acb_t res, const acb_t z, const fmpz_t k, int flags, slong prec)
{
    acb_t ez1;
    acb_init(ez1);

    /* compute e*z + 1 */
    arb_const_e(acb_realref(ez1), prec);
    acb_mul(ez1, ez1, z, prec);
    acb_add_ui(ez1, ez1, 1, prec);

    if (acb_is_exact(z))
    {
        acb_lambertw_main(res, z, ez1, k, flags, prec);
    }
    else
    {
        acb_t zz;
        mag_t err, rad;

        mag_init(err);
        mag_init(rad);
        acb_init(zz);

        acb_lambertw_bound_deriv(err, z, ez1, k);
        mag_hypot(rad, arb_radref(acb_realref(z)), arb_radref(acb_imagref(z)));
        mag_mul(err, err, rad);

        acb_set(zz, z);
        mag_zero(arb_radref(acb_realref(zz)));
        mag_zero(arb_radref(acb_imagref(zz)));  /* todo: recompute ez1? */

        acb_lambertw_main(res, zz, ez1, k, flags, prec);
        acb_add_error_mag(res, err);

        mag_clear(err);
        mag_clear(rad);
        acb_clear(zz);
    }

    acb_clear(ez1);
}
Beispiel #29
0
void
acb_sin_cos_pi(acb_t s, acb_t c, const acb_t z, slong prec)
{
#define a acb_realref(z)
#define b acb_imagref(z)
    if (arb_is_zero(b))
    {
        arb_sin_cos_pi(acb_realref(s), acb_realref(c), a, prec);
        arb_zero(acb_imagref(s));
        arb_zero(acb_imagref(c));
    }
    else if (arb_is_zero(a))
    {
        arb_t t;
        arb_init(t);
        arb_const_pi(t, prec);
        arb_mul(t, t, b, prec);
        arb_sinh_cosh(acb_imagref(s), acb_realref(c), t, prec);
        arb_zero(acb_realref(s));
        arb_zero(acb_imagref(c));
        arb_clear(t);
    }
    else
    {
        arb_t sa, ca, sb, cb;

        arb_init(sa);
        arb_init(ca);
        arb_init(sb);
        arb_init(cb);

        arb_const_pi(sb, prec);
        arb_mul(sb, sb, b, prec);

        arb_sin_cos_pi(sa, ca, a, prec);
        arb_sinh_cosh(sb, cb, sb, prec);

        arb_mul(acb_realref(s), sa, cb, prec);
        arb_mul(acb_imagref(s), sb, ca, prec);

        arb_mul(acb_realref(c), ca, cb, prec);
        arb_mul(acb_imagref(c), sa, sb, prec);
        arb_neg(acb_imagref(c), acb_imagref(c));

        arb_clear(sa);
        arb_clear(ca);
        arb_clear(sb);
        arb_clear(cb);
    }
#undef a
#undef b
}
Beispiel #30
0
void
_acb_poly_zeta_cpx_series(acb_ptr z, const acb_t s, const acb_t a, int deflate, slong d, slong prec)
{
    ulong M, N;
    slong i;
    mag_t bound;
    arb_ptr vb;
    int is_real, const_is_real;

    if (d < 1)
        return;

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

    is_real = const_is_real = 0;

    if (acb_is_real(s) && acb_is_real(a))
    {
        if (arb_is_positive(acb_realref(a)))
        {
            is_real = const_is_real = 1;
        }
        else if (arb_is_int(acb_realref(a)) &&
             arb_is_int(acb_realref(s)) &&
             arb_is_nonpositive(acb_realref(s)))
        {
            const_is_real = 1;
        }
    }

    mag_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_mag(bound, vb + i);
        arb_add_error_mag(acb_realref(z + i), bound);

        if (!is_real && !(i == 0 && const_is_real))
            arb_add_error_mag(acb_imagref(z + i), bound);
    }

    mag_clear(bound);
    _arb_vec_clear(vb, d);
}