void
acb_hypgeom_bessel_k_0f1_series(acb_poly_t res,
const acb_poly_t nu, const acb_poly_t z,
slong len, slong prec)
{
acb_poly_t s, u, A, B;
acb_poly_struct b[2];
arb_t c;
slong wlen;
int singular;
acb_poly_init(s);
acb_poly_init(u);
acb_poly_init(A);
acb_poly_init(B);
acb_poly_init(b + 0);
acb_poly_init(b + 1);
arb_init(c);
singular = (nu->length == 0) || acb_is_int(nu->coeffs);
wlen = len + (singular != 0);
/* A = (z/2)^nu, B = 1/A */
acb_poly_scalar_mul_2exp_si(A, z, -1);
acb_poly_pow_series(A, A, nu, wlen, prec);
acb_poly_inv_series(B, A, wlen, prec);
acb_poly_mullow(u, z, z, wlen, prec);
acb_poly_scalar_mul_2exp_si(u, u, -2);
acb_poly_one(b + 1);
acb_poly_add_si(b + 0, nu, 1, prec);
acb_hypgeom_pfq_series_direct(s, NULL, 0, b, 2, u, 1, -1, wlen, prec);
acb_poly_mullow(A, A, s, wlen, prec);
acb_poly_add_si(b + 0, nu, -1, prec);
acb_poly_neg(b + 0, b + 0);
acb_hypgeom_pfq_series_direct(s, NULL, 0, b, 2, u, 1, -1, wlen, prec);
acb_poly_mullow(B, B, s, wlen, prec);
acb_poly_sub(A, B, A, prec);
acb_poly_scalar_mul_2exp_si(A, A, -1);
/* multiply by pi csc(pi nu) */
acb_poly_sin_pi_series(B, nu, wlen, prec);
if (singular)
{
acb_poly_shift_right(A, A, 1);
acb_poly_shift_right(B, B, 1);
}
acb_poly_div_series(res, A, B, len, prec);
arb_const_pi(c, prec);
_acb_vec_scalar_mul_arb(res->coeffs, res->coeffs, res->length, c, prec);
acb_poly_clear(s);
acb_poly_clear(u);
acb_poly_clear(A);
acb_poly_clear(B);
acb_poly_clear(b + 0);
acb_poly_clear(b + 1);
arb_clear(c);
}
void
acb_hypgeom_pfq_series_sum_forward(acb_poly_t s, acb_poly_t t,
const acb_poly_struct * a, long p,
const acb_poly_struct * b, long q,
const acb_poly_t z, int regularized,
long n, long len, long prec)
{
acb_poly_t u, v;
acb_poly_t tmp;
long k, i;
acb_poly_init(u);
acb_poly_init(v);
acb_poly_init(tmp);
if (!regularized)
{
acb_poly_zero(s);
acb_poly_one(t);
for (k = 0; k < n && acb_poly_length(t) != 0; k++)
{
acb_poly_add(s, s, t, prec);
if (p > 0)
{
acb_poly_add_si(u, a, k, prec);
for (i = 1; i < p; i++)
{
acb_poly_add_si(v, a + i, k, prec);
acb_poly_mullow(u, u, v, len, prec);
}
acb_poly_mullow(t, t, u, len, prec);
}
if (q > 0)
{
acb_poly_add_si(u, b, k, prec);
for (i = 1; i < q; i++)
{
acb_poly_add_si(v, b + i, k, prec);
acb_poly_mullow(u, u, v, len, prec);
}
acb_poly_div_series(t, t, u, len, prec);
}
acb_poly_mullow(t, t, z, len, prec);
}
}
else
{
acb_poly_zero(s);
for (i = 0; i < q; i++)
{
if (i == 0)
{
acb_poly_rgamma_series(t, b + i, len, prec);
}
else
{
acb_poly_rgamma_series(u, b + i, len, prec);
acb_poly_mullow(tmp, t, u, len, prec);
acb_poly_swap(tmp, t);
}
}
for (k = 0; k < n; k++)
{
acb_poly_add(s, s, t, prec);
if (p > 0)
{
acb_poly_add_si(u, a, k, prec);
for (i = 1; i < p; i++)
{
acb_poly_add_si(v, a + i, k, prec);
acb_poly_mullow(tmp, u, v, len, prec);
acb_poly_swap(tmp, u);
}
acb_poly_mullow(tmp, t, u, len, prec);
acb_poly_swap(tmp, t);
}
if (q > 0)
{
acb_poly_add_si(u, b, k, prec);
for (i = 1; i < q; i++)
{
acb_poly_add_si(v, b + i, k, prec);
acb_poly_mullow(tmp, u, v, len, prec);
acb_poly_swap(tmp, u);
}
if (acb_poly_length(u) > 0 && !acb_contains_zero(u->coeffs))
{
acb_poly_div_series(tmp, t, u, len, prec);
acb_poly_mullow(t, tmp, z, len, prec);
}
else
{
/* compute term from scratch */
acb_poly_one(t);
for (i = 0; i < p; i++)
{
acb_poly_rising_ui_series(v, a + i, k + 1, len, prec);
acb_poly_mullow(t, t, v, len, prec);
}
for (i = 0; i < q; i++)
{
acb_poly_add_si(v, b + i, k + 1, prec);
acb_poly_rgamma_series(v, v, len, prec);
acb_poly_mullow(t, t, v, len, prec);
}
acb_poly_pow_ui_trunc_binexp(v, z, k + 1, len, prec);
acb_poly_mullow(t, t, v, len, prec);
}
}
else
{
acb_poly_mullow(tmp, t, z, len, prec);
acb_poly_swap(tmp, t);
}
}
}
acb_poly_clear(u);
acb_poly_clear(v);
acb_poly_clear(tmp);
}
int main()
{
slong iter;
flint_rand_t state;
flint_printf("cot_pi_series....");
fflush(stdout);
flint_randinit(state);
for (iter = 0; iter < 1000; iter++)
{
slong m, n1, bits1, bits2, bits3;
acb_poly_t S, A, B, C;
bits1 = 2 + n_randint(state, 200);
bits2 = 2 + n_randint(state, 200);
bits3 = 2 + n_randint(state, 200);
m = 1 + n_randint(state, 30);
n1 = 1 + n_randint(state, 30);
acb_poly_init(S);
acb_poly_init(A);
acb_poly_init(B);
acb_poly_init(C);
acb_poly_randtest(S, state, m, bits1, 10);
acb_poly_randtest(A, state, m, bits1, 10);
acb_poly_randtest(B, state, m, bits1, 10);
acb_poly_cot_pi_series(A, S, n1, bits2);
acb_poly_sin_cos_pi_series(B, C, S, n1, bits3);
acb_poly_div_series(B, C, B, n1, bits3);
if (!acb_poly_overlaps(A, B))
{
flint_printf("FAIL\n\n");
flint_printf("S = "); acb_poly_printd(S, 15); flint_printf("\n\n");
flint_printf("A = "); acb_poly_printd(A, 15); flint_printf("\n\n");
flint_printf("B = "); acb_poly_printd(B, 15); flint_printf("\n\n");
abort();
}
acb_poly_cot_pi_series(S, S, n1, bits2);
if (!acb_poly_overlaps(A, S))
{
flint_printf("FAIL (aliasing)\n\n");
abort();
}
acb_poly_clear(S);
acb_poly_clear(A);
acb_poly_clear(B);
acb_poly_clear(C);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");
return EXIT_SUCCESS;
}
int main()
{
slong iter;
flint_rand_t state;
flint_printf("div_series....");
fflush(stdout);
flint_randinit(state);
for (iter = 0; iter < 10000 * arb_test_multiplier(); iter++)
{
slong m, n, p, qbits, rbits1, rbits2;
fmpq_poly_t A, B, C;
acb_poly_t a, b, c, d;
qbits = 2 + n_randint(state, 200);
rbits1 = 2 + n_randint(state, 200);
rbits2 = 2 + n_randint(state, 200);
m = 1 + n_randint(state, 20);
n = 1 + n_randint(state, 20);
p = 1 + n_randint(state, 20);
fmpq_poly_init(A);
fmpq_poly_init(B);
fmpq_poly_init(C);
acb_poly_init(a);
acb_poly_init(b);
acb_poly_init(c);
acb_poly_init(d);
fmpq_poly_randtest(A, state, m, qbits);
do {
fmpq_poly_randtest_not_zero(B, state, n, qbits);
} while (B->coeffs[0] == 0);
fmpq_poly_div_series(C, A, B, p);
acb_poly_set_fmpq_poly(a, A, rbits1);
acb_poly_set_fmpq_poly(b, B, rbits1);
acb_poly_div_series(c, a, b, p, rbits2);
if (!acb_poly_contains_fmpq_poly(c, C))
{
flint_printf("FAIL\n\n");
flint_printf("bits2 = %wd\n", rbits2);
flint_printf("A = ");
fmpq_poly_print(A);
flint_printf("\n\n");
flint_printf("B = ");
fmpq_poly_print(B);
flint_printf("\n\n");
flint_printf("C = ");
fmpq_poly_print(C);
flint_printf("\n\n");
flint_printf("a = ");
acb_poly_printd(a, 15);
flint_printf("\n\n");
flint_printf("b = ");
acb_poly_printd(b, 15);
flint_printf("\n\n");
flint_printf("c = ");
acb_poly_printd(c, 15);
flint_printf("\n\n");
abort();
}
acb_poly_set(d, a);
acb_poly_div_series(d, d, b, p, rbits2);
if (!acb_poly_equal(d, c))
{
flint_printf("FAIL (aliasing 1)\n\n");
abort();
}
acb_poly_set(d, b);
acb_poly_div_series(d, a, d, p, rbits2);
if (!acb_poly_equal(d, c))
{
flint_printf("FAIL (aliasing 2)\n\n");
abort();
}
acb_poly_set(d, b);
acb_poly_div_series(c, d, d, p, rbits2);
acb_poly_div_series(d, d, d, p, rbits2);
if (!acb_poly_equal(d, c))
{
flint_printf("FAIL (aliasing 3)\n\n");
abort();
}
fmpq_poly_clear(A);
fmpq_poly_clear(B);
fmpq_poly_clear(C);
acb_poly_clear(a);
acb_poly_clear(b);
acb_poly_clear(c);
acb_poly_clear(d);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");
return EXIT_SUCCESS;
}
int main()
{
slong iter;
flint_rand_t state;
flint_printf("tan_series....");
fflush(stdout);
flint_randinit(state);
for (iter = 0; iter < 2000 * arb_test_multiplier(); iter++)
{
slong m, n, rbits1, rbits2;
acb_poly_t a, b, c, d, e;
rbits1 = 2 + n_randint(state, 100);
rbits2 = 2 + n_randint(state, 100);
if (n_randint(state, 10) == 0)
{
m = 1 + n_randint(state, 50);
n = 1 + n_randint(state, 50);
}
else
{
m = 1 + n_randint(state, 20);
n = 1 + n_randint(state, 20);
}
acb_poly_init(a);
acb_poly_init(b);
acb_poly_init(c);
acb_poly_init(d);
acb_poly_init(e);
acb_poly_randtest(a, state, m, rbits1, 10);
acb_poly_tan_series(b, a, n, rbits2);
/* check tan(x) = 2*tan(x/2)/(1-tan(x/2)^2) */
acb_poly_scalar_mul_2exp_si(c, a, -1);
acb_poly_tan_series(c, c, n, rbits2);
acb_poly_mullow(d, c, c, n, rbits2);
acb_poly_one(e);
acb_poly_sub(e, e, d, rbits2);
acb_poly_div_series(c, c, e, n, rbits2);
acb_poly_scalar_mul_2exp_si(c, c, 1);
if (!acb_poly_overlaps(b, c))
{
flint_printf("FAIL\n\n");
flint_printf("bits2 = %wd\n", rbits2);
flint_printf("a = ");
acb_poly_printd(a, 15);
flint_printf("\n\n");
flint_printf("b = ");
acb_poly_printd(b, 15);
flint_printf("\n\n");
flint_printf("c = ");
acb_poly_printd(c, 15);
flint_printf("\n\n");
abort();
}
acb_poly_tan_series(a, a, n, rbits2);
if (!acb_poly_equal(a, b))
{
flint_printf("FAIL (aliasing)\n\n");
abort();
}
acb_poly_clear(a);
acb_poly_clear(b);
acb_poly_clear(c);
acb_poly_clear(d);
acb_poly_clear(e);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");
return EXIT_SUCCESS;
}
void
acb_hypgeom_u_1f1_series(acb_poly_t res,
const acb_poly_t a, const acb_poly_t b, const acb_poly_t z,
long len, long prec)
{
acb_poly_t s, u, A, B;
acb_poly_struct aa[3];
arb_t c;
long wlen;
int singular;
acb_poly_init(s);
acb_poly_init(u);
acb_poly_init(A);
acb_poly_init(B);
acb_poly_init(aa + 0);
acb_poly_init(aa + 1);
acb_poly_init(aa + 2);
arb_init(c);
singular = (b->length == 0) || acb_is_int(b->coeffs);
wlen = len + (singular != 0);
/* A = rgamma(a-b+1) * 1F~1(a,b,z) */
acb_poly_sub(u, a, b, prec);
acb_poly_add_si(u, u, 1, prec);
acb_poly_rgamma_series(A, u, wlen, prec);
/* todo: handle a = 1 efficiently */
acb_poly_set(aa, a);
acb_poly_set(aa + 1, b);
acb_poly_one(aa + 2);
acb_hypgeom_pfq_series_direct(s, aa, 1, aa + 1, 2, z, 1, -1, wlen, prec);
acb_poly_mullow(A, A, s, wlen, prec);
/* B = rgamma(a) * 1F~1(a-b+1,2-b,z) * z^(1-b) */
acb_poly_set(aa, u);
acb_poly_add_si(aa + 1, b, -2, prec);
acb_poly_neg(aa + 1, aa + 1);
acb_hypgeom_pfq_series_direct(s, aa, 1, aa + 1, 2, z, 1, -1, wlen, prec);
acb_poly_rgamma_series(B, a, wlen, prec);
acb_poly_mullow(B, B, s, wlen, prec);
acb_poly_add_si(u, b, -1, prec);
acb_poly_neg(u, u);
acb_poly_pow_series(s, z, u, wlen, prec);
acb_poly_mullow(B, B, s, wlen, prec);
acb_poly_sub(A, A, B, prec);
/* multiply by pi csc(pi b) */
acb_poly_sin_pi_series(B, b, wlen, prec);
if (singular)
{
acb_poly_shift_right(A, A, 1);
acb_poly_shift_right(B, B, 1);
}
acb_poly_div_series(res, A, B, len, prec);
arb_const_pi(c, prec);
_acb_vec_scalar_mul_arb(res->coeffs, res->coeffs, res->length, c, prec);
acb_poly_clear(s);
acb_poly_clear(u);
acb_poly_clear(A);
acb_poly_clear(B);
acb_poly_clear(aa + 0);
acb_poly_clear(aa + 1);
acb_poly_clear(aa + 2);
arb_clear(c);
}
