/* assumes no aliasing */
slong
acb_lambertw_initial(acb_t res, const acb_t z, const acb_t ez1, const fmpz_t k, slong prec)
{
/* Handle z very close to 0 on the principal branch. */
if (fmpz_is_zero(k) &&
(arf_cmpabs_2exp_si(arb_midref(acb_realref(z)), -20) <= 0 &&
arf_cmpabs_2exp_si(arb_midref(acb_imagref(z)), -20) <= 0))
{
acb_set(res, z);
acb_submul(res, res, res, prec);
return 40; /* could be tightened... */
}
/* For moderate input not close to the branch point, compute a double
approximation as the initial value. */
if (fmpz_is_zero(k) &&
arf_cmpabs_2exp_si(arb_midref(acb_realref(z)), 400) < 0 &&
arf_cmpabs_2exp_si(arb_midref(acb_imagref(z)), 400) < 0 &&
(arf_cmp_d(arb_midref(acb_realref(z)), -0.37) < 0 ||
arf_cmp_d(arb_midref(acb_realref(z)), -0.36) > 0 ||
arf_cmpabs_d(arb_midref(acb_imagref(z)), 0.01) > 0))
{
acb_lambertw_principal_d(res, z);
return 48;
}
/* Check if we are close to the branch point at -1/e. */
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))))
&& ((arf_cmpabs_2exp_si(arb_midref(acb_realref(ez1)), -2) <= 0 &&
arf_cmpabs_2exp_si(arb_midref(acb_imagref(ez1)), -2) <= 0)))
{
acb_t t;
acb_init(t);
acb_mul_2exp_si(t, ez1, 1);
mag_zero(arb_radref(acb_realref(t)));
mag_zero(arb_radref(acb_imagref(t)));
acb_mul_ui(t, t, 3, prec);
acb_sqrt(t, t, prec);
if (!fmpz_is_zero(k))
acb_neg(t, t);
acb_lambertw_branchpoint_series(res, t, 0, prec);
acb_clear(t);
return 1; /* todo: estimate */
}
acb_lambertw_initial_asymp(res, z, k, prec);
return 1; /* todo: estimate */
}
/* f(z) = sech(10(x-0.2))^2 + sech(100(x-0.4))^4 + sech(1000(x-0.6))^6 */
int
f_spike(acb_ptr res, const acb_t z, void * param, slong order, slong prec)
{
acb_t a, b, c;
if (order > 1)
flint_abort(); /* Would be needed for Taylor method. */
acb_init(a);
acb_init(b);
acb_init(c);
acb_mul_ui(a, z, 10, prec);
acb_sub_ui(a, a, 2, prec);
acb_sech(a, a, prec);
acb_pow_ui(a, a, 2, prec);
acb_mul_ui(b, z, 100, prec);
acb_sub_ui(b, b, 40, prec);
acb_sech(b, b, prec);
acb_pow_ui(b, b, 4, prec);
acb_mul_ui(c, z, 1000, prec);
acb_sub_ui(c, c, 600, prec);
acb_sech(c, c, prec);
acb_pow_ui(c, c, 6, prec);
acb_add(res, a, b, prec);
acb_add(res, res, c, prec);
acb_clear(a);
acb_clear(b);
acb_clear(c);
return 0;
}
void
acb_modular_eisenstein(acb_ptr r, const acb_t tau, slong len, slong prec)
{
psl2z_t g;
arf_t one_minus_eps;
acb_t tau_prime, t1, t2, t3, t4, q;
slong m, n;
if (len < 1)
return;
psl2z_init(g);
arf_init(one_minus_eps);
acb_init(tau_prime);
acb_init(t1);
acb_init(t2);
acb_init(t3);
acb_init(t4);
acb_init(q);
arf_set_ui_2exp_si(one_minus_eps, 63, -6);
acb_modular_fundamental_domain_approx(tau_prime, g, tau,
one_minus_eps, prec);
acb_exp_pi_i(q, tau_prime, prec);
acb_modular_theta_const_sum(t2, t3, t4, q, prec);
/* fourth powers of the theta functions (a, b, c) */
acb_mul(t2, t2, t2, prec);
acb_mul(t2, t2, t2, prec);
acb_mul(t2, t2, q, prec);
acb_mul(t3, t3, t3, prec);
acb_mul(t3, t3, t3, prec);
acb_mul(t4, t4, t4, prec);
acb_mul(t4, t4, t4, prec);
/* c2 = pi^4 * (a^8 + b^8 + c^8) / 30 */
/* c3 = pi^6 * (b^12 + c^12 - 3a^8 * (b^4+c^4)) / 180 */
/* r = a^8 */
acb_mul(r, t2, t2, prec);
if (len > 1)
{
/* r[1] = -3 a^8 * (b^4 + c^4) */
acb_add(r + 1, t3, t4, prec);
acb_mul(r + 1, r + 1, r, prec);
acb_mul_si(r + 1, r + 1, -3, prec);
}
/* b^8 */
acb_mul(t1, t3, t3, prec);
acb_add(r, r, t1, prec);
/* b^12 */
if (len > 1)
acb_addmul(r + 1, t1, t3, prec);
/* c^8 */
acb_mul(t1, t4, t4, prec);
acb_add(r, r, t1, prec);
/* c^12 */
if (len > 1)
acb_addmul(r + 1, t1, t4, prec);
acb_const_pi(t1, prec);
acb_mul(t1, t1, t1, prec);
acb_mul(t2, t1, t1, prec);
acb_mul(r, r, t2, prec);
acb_div_ui(r, r, 30, prec);
if (len > 1)
{
acb_mul(t2, t2, t1, prec);
acb_mul(r + 1, r + 1, t2, prec);
acb_div_ui(r + 1, r + 1, 189, prec);
}
/* apply modular transformation */
if (!fmpz_is_zero(&g->c))
{
acb_mul_fmpz(t1, tau, &g->c, prec);
acb_add_fmpz(t1, t1, &g->d, prec);
acb_inv(t1, t1, prec);
acb_mul(t1, t1, t1, prec);
acb_mul(t2, t1, t1, prec);
acb_mul(r, r, t2, prec);
if (len > 1)
{
acb_mul(t2, t1, t2, prec);
acb_mul(r + 1, r + 1, t2, prec);
}
}
/* compute more coefficients using recurrence */
for (n = 4; n < len + 2; n++)
{
acb_zero(r + n - 2);
m = 2;
for (m = 2; m * 2 < n; m++)
acb_addmul(r + n - 2, r + m - 2, r + n - m - 2, prec);
acb_mul_2exp_si(r + n - 2, r + n - 2, 1);
if (n % 2 == 0)
acb_addmul(r + n - 2, r + n / 2 - 2, r + n / 2 - 2, prec);
acb_mul_ui(r + n - 2, r + n - 2, 3, prec);
acb_div_ui(r + n - 2, r + n - 2, (2 * n + 1) * (n - 3), prec);
}
/* convert c's to G's */
for (n = 0; n < len; n++)
acb_div_ui(r + n, r + n, 2 * n + 3, prec);
psl2z_clear(g);
arf_clear(one_minus_eps);
acb_clear(tau_prime);
acb_clear(t1);
acb_clear(t2);
acb_clear(t3);
acb_clear(t4);
acb_clear(q);
}
int main(int argc, char *argv[])
{
acb_t s, t, a, b;
mag_t tol;
slong prec, goal;
slong N;
ulong k;
int integral, ifrom, ito;
int i, twice, havegoal, havetol;
acb_calc_integrate_opt_t options;
ifrom = ito = -1;
for (i = 1; i < argc; i++)
{
if (!strcmp(argv[i], "-i"))
{
if (!strcmp(argv[i+1], "all"))
{
ifrom = 0;
ito = NUM_INTEGRALS - 1;
}
else
{
ifrom = ito = atol(argv[i+1]);
if (ito < 0 || ito >= NUM_INTEGRALS)
flint_abort();
}
}
}
if (ifrom == -1)
{
flint_printf("Compute integrals using acb_calc_integrate.\n");
flint_printf("Usage: integrals -i n [-prec p] [-tol eps] [-twice] [...]\n\n");
flint_printf("-i n - compute integral n (0 <= n <= %d), or \"-i all\"\n", NUM_INTEGRALS - 1);
flint_printf("-prec p - precision in bits (default p = 64)\n");
flint_printf("-goal p - approximate relative accuracy goal (default p)\n");
flint_printf("-tol eps - approximate absolute error goal (default 2^-p)\n");
flint_printf("-twice - run twice (to see overhead of computing nodes)\n");
flint_printf("-heap - use heap for subinterval queue\n");
flint_printf("-verbose - show information\n");
flint_printf("-verbose2 - show more information\n");
flint_printf("-deg n - use quadrature degree up to n\n");
flint_printf("-eval n - limit number of function evaluations to n\n");
flint_printf("-depth n - limit subinterval queue size to n\n\n");
flint_printf("Implemented integrals:\n");
for (integral = 0; integral < NUM_INTEGRALS; integral++)
flint_printf("I%d = %s\n", integral, descr[integral]);
flint_printf("\n");
return 1;
}
acb_calc_integrate_opt_init(options);
prec = 64;
twice = 0;
goal = 0;
havetol = havegoal = 0;
acb_init(a);
acb_init(b);
acb_init(s);
acb_init(t);
mag_init(tol);
for (i = 1; i < argc; i++)
{
if (!strcmp(argv[i], "-prec"))
{
prec = atol(argv[i+1]);
}
else if (!strcmp(argv[i], "-twice"))
{
twice = 1;
}
else if (!strcmp(argv[i], "-goal"))
{
goal = atol(argv[i+1]);
if (goal < 0)
{
flint_printf("expected goal >= 0\n");
return 1;
}
havegoal = 1;
}
else if (!strcmp(argv[i], "-tol"))
{
arb_t x;
arb_init(x);
arb_set_str(x, argv[i+1], 10);
arb_get_mag(tol, x);
arb_clear(x);
havetol = 1;
}
else if (!strcmp(argv[i], "-deg"))
{
options->deg_limit = atol(argv[i+1]);
}
else if (!strcmp(argv[i], "-eval"))
{
options->eval_limit = atol(argv[i+1]);
}
else if (!strcmp(argv[i], "-depth"))
{
options->depth_limit = atol(argv[i+1]);
}
else if (!strcmp(argv[i], "-verbose"))
{
options->verbose = 1;
}
else if (!strcmp(argv[i], "-verbose2"))
{
options->verbose = 2;
}
else if (!strcmp(argv[i], "-heap"))
{
options->use_heap = 1;
}
}
if (!havegoal)
goal = prec;
if (!havetol)
mag_set_ui_2exp_si(tol, 1, -prec);
for (integral = ifrom; integral <= ito; integral++)
{
flint_printf("I%d = %s ...\n", integral, descr[integral]);
for (i = 0; i < 1 + twice; i++)
{
TIMEIT_ONCE_START
switch (integral)
{
case 0:
acb_set_d(a, 0);
acb_set_d(b, 100);
acb_calc_integrate(s, f_sin, NULL, a, b, goal, tol, options, prec);
break;
case 1:
acb_set_d(a, 0);
acb_set_d(b, 1);
acb_calc_integrate(s, f_atanderiv, NULL, a, b, goal, tol, options, prec);
acb_mul_2exp_si(s, s, 2);
break;
case 2:
acb_set_d(a, 0);
acb_one(b);
acb_mul_2exp_si(b, b, goal);
acb_calc_integrate(s, f_atanderiv, NULL, a, b, goal, tol, options, prec);
arb_add_error_2exp_si(acb_realref(s), -goal);
acb_mul_2exp_si(s, s, 1);
break;
case 3:
acb_set_d(a, 0);
acb_set_d(b, 1);
acb_calc_integrate(s, f_circle, NULL, a, b, goal, tol, options, prec);
acb_mul_2exp_si(s, s, 2);
break;
case 4:
acb_set_d(a, 0);
acb_set_d(b, 8);
acb_calc_integrate(s, f_rump, NULL, a, b, goal, tol, options, prec);
break;
case 5:
acb_set_d(a, 1);
acb_set_d(b, 101);
acb_calc_integrate(s, f_floor, NULL, a, b, goal, tol, options, prec);
break;
case 6:
acb_set_d(a, 0);
acb_set_d(b, 1);
acb_calc_integrate(s, f_helfgott, NULL, a, b, goal, tol, options, prec);
break;
case 7:
acb_zero(s);
acb_set_d_d(a, -1.0, -1.0);
acb_set_d_d(b, 2.0, -1.0);
acb_calc_integrate(t, f_zeta, NULL, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, 2.0, -1.0);
acb_set_d_d(b, 2.0, 1.0);
acb_calc_integrate(t, f_zeta, NULL, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, 2.0, 1.0);
acb_set_d_d(b, -1.0, 1.0);
acb_calc_integrate(t, f_zeta, NULL, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, -1.0, 1.0);
acb_set_d_d(b, -1.0, -1.0);
acb_calc_integrate(t, f_zeta, NULL, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_const_pi(t, prec);
acb_div(s, s, t, prec);
acb_mul_2exp_si(s, s, -1);
acb_div_onei(s, s);
break;
case 8:
acb_set_d(a, 0);
acb_set_d(b, 1);
acb_calc_integrate(s, f_essing, NULL, a, b, goal, tol, options, prec);
break;
case 9:
acb_set_d(a, 0);
acb_set_d(b, 1);
acb_calc_integrate(s, f_essing2, NULL, a, b, goal, tol, options, prec);
break;
case 10:
acb_set_d(a, 0);
acb_set_d(b, 10000);
acb_calc_integrate(s, f_factorial1000, NULL, a, b, goal, tol, options, prec);
break;
case 11:
acb_set_d_d(a, 1.0, 0.0);
acb_set_d_d(b, 1.0, 1000.0);
acb_calc_integrate(s, f_gamma, NULL, a, b, goal, tol, options, prec);
break;
case 12:
acb_set_d(a, -10.0);
acb_set_d(b, 10.0);
acb_calc_integrate(s, f_sin_plus_small, NULL, a, b, goal, tol, options, prec);
break;
case 13:
acb_set_d(a, -1020.0);
acb_set_d(b, -1010.0);
acb_calc_integrate(s, f_exp, NULL, a, b, goal, tol, options, prec);
break;
case 14:
acb_set_d(a, 0);
acb_set_d(b, ceil(sqrt(goal * 0.693147181) + 1.0));
acb_calc_integrate(s, f_gaussian, NULL, a, b, goal, tol, options, prec);
acb_mul(b, b, b, prec);
acb_neg(b, b);
acb_exp(b, b, prec);
arb_add_error(acb_realref(s), acb_realref(b));
break;
case 15:
acb_set_d(a, 0.0);
acb_set_d(b, 1.0);
acb_calc_integrate(s, f_spike, NULL, a, b, goal, tol, options, prec);
break;
case 16:
acb_set_d(a, 0.0);
acb_set_d(b, 8.0);
acb_calc_integrate(s, f_monster, NULL, a, b, goal, tol, options, prec);
break;
case 17:
acb_set_d(a, 0);
acb_set_d(b, ceil(goal * 0.693147181 + 1.0));
acb_calc_integrate(s, f_sech, NULL, a, b, goal, tol, options, prec);
acb_neg(b, b);
acb_exp(b, b, prec);
acb_mul_2exp_si(b, b, 1);
arb_add_error(acb_realref(s), acb_realref(b));
break;
case 18:
acb_set_d(a, 0);
acb_set_d(b, ceil(goal * 0.693147181 / 3.0 + 2.0));
acb_calc_integrate(s, f_sech3, NULL, a, b, goal, tol, options, prec);
acb_neg(b, b);
acb_mul_ui(b, b, 3, prec);
acb_exp(b, b, prec);
acb_mul_2exp_si(b, b, 3);
acb_div_ui(b, b, 3, prec);
arb_add_error(acb_realref(s), acb_realref(b));
break;
case 19:
if (goal < 0)
abort();
/* error bound 2^-N (1+N) when truncated at 2^-N */
N = goal + FLINT_BIT_COUNT(goal);
acb_one(a);
acb_mul_2exp_si(a, a, -N);
acb_one(b);
acb_calc_integrate(s, f_log_div1p, NULL, a, b, goal, tol, options, prec);
acb_set_ui(b, N + 1);
acb_mul_2exp_si(b, b, -N);
arb_add_error(acb_realref(s), acb_realref(b));
break;
case 20:
if (goal < 0)
abort();
/* error bound (N+1) exp(-N) when truncated at N */
N = goal + FLINT_BIT_COUNT(goal);
acb_zero(a);
acb_set_ui(b, N);
acb_calc_integrate(s, f_log_div1p_transformed, NULL, a, b, goal, tol, options, prec);
acb_neg(b, b);
acb_exp(b, b, prec);
acb_mul_ui(b, b, N + 1, prec);
arb_add_error(acb_realref(s), acb_realref(b));
break;
case 21:
acb_zero(s);
N = 10;
acb_set_d_d(a, 0.5, -0.5);
acb_set_d_d(b, 0.5, 0.5);
acb_calc_integrate(t, f_elliptic_p_laurent_n, &N, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, 0.5, 0.5);
acb_set_d_d(b, -0.5, 0.5);
acb_calc_integrate(t, f_elliptic_p_laurent_n, &N, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, -0.5, 0.5);
acb_set_d_d(b, -0.5, -0.5);
acb_calc_integrate(t, f_elliptic_p_laurent_n, &N, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, -0.5, -0.5);
acb_set_d_d(b, 0.5, -0.5);
acb_calc_integrate(t, f_elliptic_p_laurent_n, &N, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_const_pi(t, prec);
acb_div(s, s, t, prec);
acb_mul_2exp_si(s, s, -1);
acb_div_onei(s, s);
break;
case 22:
acb_zero(s);
N = 1000;
acb_set_d_d(a, 100.0, 0.0);
acb_set_d_d(b, 100.0, N);
acb_calc_integrate(t, f_zeta_frac, NULL, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_set_d_d(a, 100, N);
acb_set_d_d(b, 0.5, N);
acb_calc_integrate(t, f_zeta_frac, NULL, a, b, goal, tol, options, prec);
acb_add(s, s, t, prec);
acb_div_onei(s, s);
arb_zero(acb_imagref(s));
acb_set_ui(t, N);
acb_dirichlet_hardy_theta(t, t, NULL, NULL, 1, prec);
acb_add(s, s, t, prec);
acb_const_pi(t, prec);
acb_div(s, s, t, prec);
acb_add_ui(s, s, 1, prec);
break;
case 23:
acb_set_d(a, 0.0);
acb_set_d(b, 1000.0);
acb_calc_integrate(s, f_lambertw, NULL, a, b, goal, tol, options, prec);
break;
case 24:
acb_set_d(a, 0.0);
acb_const_pi(b, prec);
acb_calc_integrate(s, f_max_sin_cos, NULL, a, b, goal, tol, options, prec);
break;
case 25:
acb_set_si(a, -1);
acb_set_si(b, 1);
acb_calc_integrate(s, f_erf_bent, NULL, a, b, goal, tol, options, prec);
break;
case 26:
acb_set_si(a, -10);
acb_set_si(b, 10);
acb_calc_integrate(s, f_airy_ai, NULL, a, b, goal, tol, options, prec);
break;
case 27:
acb_set_si(a, 0);
acb_set_si(b, 10);
acb_calc_integrate(s, f_horror, NULL, a, b, goal, tol, options, prec);
break;
case 28:
acb_set_d_d(a, -1, -1);
acb_set_d_d(b, -1, 1);
acb_calc_integrate(s, f_sqrt, NULL, a, b, goal, tol, options, prec);
break;
case 29:
acb_set_d(a, 0);
acb_set_d(b, ceil(sqrt(goal * 0.693147181) + 1.0));
acb_calc_integrate(s, f_gaussian_twist, NULL, a, b, goal, tol, options, prec);
acb_mul(b, b, b, prec);
acb_neg(b, b);
acb_exp(b, b, prec);
arb_add_error(acb_realref(s), acb_realref(b));
arb_add_error(acb_imagref(s), acb_realref(b));
break;
case 30:
acb_set_d(a, 0);
acb_set_d(b, ceil(goal * 0.693147181 + 1.0));
acb_calc_integrate(s, f_exp_airy, NULL, a, b, goal, tol, options, prec);
acb_neg(b, b);
acb_exp(b, b, prec);
acb_mul_2exp_si(b, b, 1);
arb_add_error(acb_realref(s), acb_realref(b));
break;
case 31:
acb_zero(a);
acb_const_pi(b, prec);
acb_calc_integrate(s, f_sin_cos_frac, NULL, a, b, goal, tol, options, prec);
break;
case 32:
acb_zero(a);
acb_set_ui(b, 3);
acb_calc_integrate(s, f_sin_near_essing, NULL, a, b, goal, tol, options, prec);
break;
case 33:
acb_zero(a);
acb_zero(b);
k = 3;
scaled_bessel_select_N(acb_realref(b), k, prec);
acb_calc_integrate(s, f_scaled_bessel, &k, a, b, goal, tol, options, prec);
scaled_bessel_tail_bound(acb_realref(a), k, acb_realref(b), prec);
arb_add_error(acb_realref(s), acb_realref(a));
break;
case 34:
acb_zero(a);
acb_zero(b);
k = 15;
scaled_bessel_select_N(acb_realref(b), k, prec);
acb_calc_integrate(s, f_scaled_bessel, &k, a, b, goal, tol, options, prec);
scaled_bessel_tail_bound(acb_realref(a), k, acb_realref(b), prec);
arb_add_error(acb_realref(s), acb_realref(a));
break;
case 35:
acb_set_d_d(a, -1, -1);
acb_set_d_d(b, -1, 1);
acb_calc_integrate(s, f_rsqrt, NULL, a, b, goal, tol, options, prec);
break;
default:
abort();
}
TIMEIT_ONCE_STOP
}
flint_printf("I%d = ", integral);
acb_printn(s, 3.333 * prec, 0);
flint_printf("\n\n");
}
acb_clear(a);
acb_clear(b);
acb_clear(s);
acb_clear(t);
mag_clear(tol);
flint_cleanup();
return 0;
}
static void
evaluate(acb_poly_t A, acb_srcptr a, slong p, const acb_t z, slong n, slong prec)
{
acb_poly_fit_length(A, p + 1);
if (p == 1)
{
acb_add_ui(A->coeffs, a, n, prec);
if (z != NULL)
acb_mul(A->coeffs, A->coeffs, z, prec);
}
else if (p == 2)
{
acb_add(A->coeffs, a + 0, a + 1, prec);
acb_add_ui(A->coeffs + 1, A->coeffs, 2 * n, prec);
acb_add_ui(A->coeffs, A->coeffs, n, prec);
acb_mul_ui(A->coeffs, A->coeffs, n, prec);
acb_addmul(A->coeffs, a + 0, a + 1, prec);
if (z != NULL)
{
acb_mul(A->coeffs, A->coeffs, z, prec);
acb_mul(A->coeffs + 1, A->coeffs + 1, z, prec);
}
}
else if (p == 3)
{
acb_t t, u;
acb_init(t);
acb_init(u);
acb_add(t, a + 0, a + 1, prec);
acb_add(t, t, a + 2, prec);
acb_mul(u, a + 0, a + 1, prec);
acb_mul(A->coeffs, u, a + 2, prec);
acb_addmul(u, a + 0, a + 2, prec);
acb_addmul(u, a + 1, a + 2, prec);
/*
(a0 + n)(a1 + n)(a2 + n) = a0 a1 a2 + (a0 a1 + a0 a2 + a1 a2) n + (a0 + a1 + a2) n^2 + n^3
(a0 a1 + a0 a2 + a1 a2) + 2 (a0 + a1 + a2) n + 3 n^2
(a0 + a1 + a2) + 3n
1
*/
acb_addmul_ui(A->coeffs, u, n, prec);
acb_addmul_ui(A->coeffs, t, n * n, prec);
acb_add_ui(A->coeffs, A->coeffs, n * n * n, prec);
acb_set(A->coeffs + 1, u);
acb_addmul_ui(A->coeffs + 1, t, 2 * n, prec);
acb_add_ui(A->coeffs + 1, A->coeffs + 1, 3 * n * n, prec);
acb_add_ui(A->coeffs + 2, t, 3 * n, prec);
if (z != NULL)
{
acb_mul(A->coeffs + 0, A->coeffs + 0, z, prec);
acb_mul(A->coeffs + 1, A->coeffs + 1, z, prec);
acb_mul(A->coeffs + 2, A->coeffs + 2, z, prec);
}
acb_clear(t);
acb_clear(u);
}
else if (p != 0)
{
flint_abort();
}
if (z != NULL)
acb_set(A->coeffs + p, z);
else
acb_one(A->coeffs + p);
_acb_poly_set_length(A, p + 1);
_acb_poly_normalise(A);
}
int main()
{
long iter;
flint_rand_t state;
printf("elliptic_p_zpx....");
fflush(stdout);
flint_randinit(state);
/* Test differential equation */
for (iter = 0; iter < 5000; iter++)
{
acb_t tau, z;
acb_ptr g, wp, wp3, wpd, wpd2;
long prec, len, i;
len = 1 + n_randint(state, 15);
prec = 2 + n_randint(state, 1000);
acb_init(tau);
acb_init(z);
g = _acb_vec_init(2);
wp = _acb_vec_init(len + 1);
wp3 = _acb_vec_init(len);
wpd = _acb_vec_init(len);
wpd2 = _acb_vec_init(len);
acb_randtest(tau, state, prec, 10);
acb_randtest(z, state, prec, 10);
acb_modular_elliptic_p_zpx(wp, z, tau, len + 1, prec);
acb_modular_eisenstein(g, tau, 2, prec);
acb_mul_ui(g, g, 60, prec);
acb_mul_ui(g + 1, g + 1, 140, prec);
_acb_poly_derivative(wpd, wp, len + 1, prec);
_acb_poly_mullow(wpd2, wpd, len, wpd, len, len, prec);
_acb_poly_pow_ui_trunc_binexp(wp3, wp, len, 3, len, prec);
_acb_vec_scalar_mul_ui(wp3, wp3, len, 4, prec);
_acb_vec_scalar_submul(wp3, wp, len, g, prec);
acb_sub(wp3, wp3, g + 1, prec);
for (i = 0; i < len; i++)
{
if (!acb_overlaps(wpd2 + i, wp3 + i))
{
printf("FAIL (overlap)\n");
printf("i = %ld len = %ld prec = %ld\n\n", i, len, prec);
printf("z = "); acb_printd(z, 15); printf("\n\n");
printf("tau = "); acb_printd(tau, 15); printf("\n\n");
printf("wp = "); acb_printd(wp + i, 15); printf("\n\n");
printf("wpd = "); acb_printd(wpd + i, 15); printf("\n\n");
printf("wp3 = "); acb_printd(wp3 + i, 15); printf("\n\n");
abort();
}
}
acb_clear(tau);
acb_clear(z);
_acb_vec_clear(g, 2);
_acb_vec_clear(wp, len + 1);
_acb_vec_clear(wp3, len);
_acb_vec_clear(wpd, len);
_acb_vec_clear(wpd2, len);
}
/* Consistency test */
for (iter = 0; iter < 5000; iter++)
{
acb_t tau, z;
acb_ptr wp1, wp2;
long prec1, prec2, len1, len2, i;
len1 = n_randint(state, 15);
len2 = n_randint(state, 15);
prec1 = 2 + n_randint(state, 1000);
prec2 = 2 + n_randint(state, 1000);
acb_init(tau);
acb_init(z);
wp1 = _acb_vec_init(len1);
wp2 = _acb_vec_init(len2);
acb_randtest(tau, state, prec1, 10);
acb_randtest(z, state, prec1, 10);
acb_modular_elliptic_p_zpx(wp1, z, tau, len1, prec1);
acb_modular_elliptic_p_zpx(wp2, z, tau, len2, prec2);
for (i = 0; i < FLINT_MIN(len1, len2); i++)
{
if (!acb_overlaps(wp1 + i, wp2 + i))
{
printf("FAIL (overlap)\n");
printf("i = %ld len1 = %ld len2 = %ld\n\n", i, len1, len2);
printf("tau = "); acb_printd(tau, 15); printf("\n\n");
printf("z = "); acb_printd(z, 15); printf("\n\n");
printf("wp1 = "); acb_printd(wp1 + i, 15); printf("\n\n");
printf("wp2 = "); acb_printd(wp2 + i, 15); printf("\n\n");
abort();
}
}
acb_clear(tau);
acb_clear(z);
_acb_vec_clear(wp1, len1);
_acb_vec_clear(wp2, len2);
}
flint_randclear(state);
flint_cleanup();
printf("PASS\n");
return EXIT_SUCCESS;
}
int main()
{
slong iter;
flint_rand_t state;
flint_printf("bernoulli_poly_ui....");
fflush(stdout);
flint_randinit(state);
/* test multiplication theorem */
for (iter = 0; iter < 1000 * arb_test_multiplier(); iter++)
{
acb_t x, t, res1, res2;
ulong n, m, k;
slong prec;
n = n_randint(state, 50);
m = 1 + n_randint(state, 5);
prec = 2 + n_randint(state, 200);
acb_init(x);
acb_init(t);
acb_init(res1);
acb_init(res2);
acb_randtest(x, state, 2 + n_randint(state, 200), 20);
acb_randtest(res1, state, 2 + n_randint(state, 200), 20);
acb_mul_ui(t, x, m, prec);
acb_bernoulli_poly_ui(res1, n, t, prec);
acb_zero(res2);
for (k = 0; k < m; k++)
{
acb_set_ui(t, k);
acb_div_ui(t, t, m, prec);
acb_add(t, t, x, prec);
acb_bernoulli_poly_ui(t, n, t, prec);
acb_add(res2, res2, t, prec);
}
if (n > 0)
{
arb_ui_pow_ui(acb_realref(t), m, n - 1, prec);
acb_mul_arb(res2, res2, acb_realref(t), prec);
}
else
{
acb_div_ui(res2, res2, m, prec);
}
if (!acb_overlaps(res1, res2))
{
flint_printf("FAIL: overlap\n\n");
flint_printf("n = %wu, m = %wu\n\n", n, m);
flint_printf("x = "); acb_printd(x, 15); flint_printf("\n\n");
flint_printf("res1 = "); acb_printd(res1, 15); flint_printf("\n\n");
flint_printf("res2 = "); acb_printd(res2, 15); flint_printf("\n\n");
abort();
}
acb_clear(x);
acb_clear(t);
acb_clear(res1);
acb_clear(res2);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");
return EXIT_SUCCESS;
}
void
acb_modular_elliptic_k_cpx(acb_ptr w, const acb_t m, slong len, slong prec)
{
acb_t t, u, msub1m, m2sub1;
slong k, n;
if (len < 1)
return;
if (len == 1)
{
acb_modular_elliptic_k(w, m, prec);
return;
}
if (acb_is_zero(m))
{
acb_const_pi(w, prec);
acb_mul_2exp_si(w, w, -1);
for (k = 1; k < len; k++)
{
acb_mul_ui(w + k, w + k - 1, (2 * k - 1) * (2 * k - 1), prec);
acb_div_ui(w + k, w + k, 4 * k * k, prec);
}
return;
}
acb_init(t);
acb_init(u);
acb_init(msub1m);
acb_init(m2sub1);
acb_sub_ui(msub1m, m, 1, prec);
acb_neg(t, msub1m);
acb_sqrt(t, t, prec);
acb_mul(msub1m, msub1m, m, prec);
acb_mul_2exp_si(m2sub1, m, 1);
acb_sub_ui(m2sub1, m2sub1, 1, prec);
acb_agm1_cpx(w, t, 2, prec);
/* pi M'(t) / (4 t M(t)^2) */
acb_mul(u, w, w, prec);
acb_mul(t, t, u, prec);
acb_div(w + 1, w + 1, t, prec);
acb_const_pi(u, prec);
acb_mul(w + 1, w + 1, u, prec);
acb_mul_2exp_si(w + 1, w + 1, -2);
/* pi / (2 M(t)) */
acb_const_pi(u, prec);
acb_div(w, u, w, prec);
acb_mul_2exp_si(w, w, -1);
acb_inv(t, msub1m, prec);
for (k = 2; k < len; k++)
{
n = k - 2;
acb_mul_ui(w + k, w + n, (2 * n + 1) * (2 * n + 1), prec);
acb_mul(u, w + n + 1, m2sub1, prec);
acb_addmul_ui(w + k, u, (n + 1) * (n + 1) * 4, prec);
acb_mul(w + k, w + k, t, prec);
acb_div_ui(w + k, w + k, 4 * (n + 1) * (n + 2), prec);
acb_neg(w + k, w + k);
}
acb_clear(t);
acb_clear(u);
acb_clear(msub1m);
acb_clear(m2sub1);
}
/*
F(x) = c0 + c1 x + c2 x^2 + c3 x^3 + [...]
F'(x) = c1 + 2 c2 x + 3 c3 x^2 + 4 c4 x^3 + [...]
*/
static void
evaluate_sum(acb_t res, acb_t res1,
const acb_t a, const acb_t b, const acb_t c, const acb_t y,
const acb_t x, const acb_t f0, const acb_t f1, long num, long prec)
{
acb_t s, s2, w, d, e, xpow, ck, cknext;
long k;
acb_init(s);
acb_init(s2);
acb_init(w);
acb_init(d);
acb_init(e);
acb_init(xpow);
acb_init(ck);
acb_init(cknext);
/* d = (y-1)*y */
acb_sub_ui(d, y, 1, prec);
acb_mul(d, d, y, prec);
acb_one(xpow);
for (k = 0; k < num; k++)
{
if (k == 0)
{
acb_set(ck, f0);
acb_set(cknext, f1);
}
else
{
acb_add_ui(w, b, k-1, prec);
acb_mul(w, w, ck, prec);
acb_add_ui(e, a, k-1, prec);
acb_mul(w, w, e, prec);
acb_add(e, a, b, prec);
acb_add_ui(e, e, 2*(k+1)-3, prec);
acb_mul(e, e, y, prec);
acb_sub(e, e, c, prec);
acb_sub_ui(e, e, k-1, prec);
acb_mul_ui(e, e, k, prec);
acb_addmul(w, e, cknext, prec);
acb_mul_ui(e, d, k+1, prec);
acb_mul_ui(e, e, k, prec);
acb_div(w, w, e, prec);
acb_neg(w, w);
acb_set(ck, cknext);
acb_set(cknext, w);
}
acb_addmul(s, ck, xpow, prec);
acb_mul_ui(w, cknext, k+1, prec);
acb_addmul(s2, w, xpow, prec);
acb_mul(xpow, xpow, x, prec);
}
acb_set(res, s);
acb_set(res1, s2);
acb_clear(s);
acb_clear(s2);
acb_clear(w);
acb_clear(d);
acb_clear(e);
acb_clear(xpow);
acb_clear(ck);
acb_clear(cknext);
}
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;
}
