#include "test_helpers.h"
#include "arb.h"
TEST_FUNCTION_START(arb_lambertw, state)
{
slong iter;
for (iter = 0; iter < 10000 * 0.1 * flint_test_multiplier(); iter++)
{
arb_t x1, x2, t, w1, w2;
slong prec1, prec2, ebits;
int branch;
arb_init(x1);
arb_init(x2);
arb_init(t);
arb_init(w1);
arb_init(w2);
branch = n_randint(state, 2);
if (n_randint(state, 4) == 0)
{
prec1 = 2 + n_randint(state, 3000);
prec2 = 2 + n_randint(state, 3000);
ebits = 1 + n_randint(state, 1000);
}
else
{
prec1 = 2 + n_randint(state, 300);
prec2 = 2 + n_randint(state, 300);
ebits = 1 + n_randint(state, 50);
}
arb_randtest(x1, state, 1 + n_randint(state, 1000), ebits);
arb_randtest(x2, state, 1 + n_randint(state, 1000), ebits);
arb_randtest(t, state, 1 + n_randint(state, 1000), ebits);
arb_randtest(w1, state, 1 + n_randint(state, 1000), ebits);
arb_randtest(w2, state, 1 + n_randint(state, 1000), ebits);
if (n_randint(state, 4) == 0)
{
arb_const_e(t, 2 * prec1);
arb_inv(t, t, 2 * prec1);
arb_sub(x1, x1, t, 2 * prec1);
}
if (n_randint(state, 2))
{
arb_set(x2, x1);
}
else
{
arb_add(x2, x1, t, 2 * prec1);
arb_sub(x2, x2, t, 2 * prec1);
}
arb_lambertw(w1, x1, branch, prec1);
if (n_randint(state, 2))
{
arb_set(w2, x2);
arb_lambertw(w2, w2, branch, prec1);
}
else
{
arb_lambertw(w2, x2, branch, prec1);
}
if (!arb_overlaps(w1, w2))
{
flint_printf("FAIL: overlap\n\n");
flint_printf("branch = %d, prec1 = %wd, prec2 = %wd\n\n", branch, prec1, prec2);
flint_printf("x1 = "); arb_printd(x1, 50); flint_printf("\n\n");
flint_printf("x2 = "); arb_printd(x2, 50); flint_printf("\n\n");
flint_printf("w1 = "); arb_printd(w1, 50); flint_printf("\n\n");
flint_printf("w2 = "); arb_printd(w2, 50); flint_printf("\n\n");
flint_abort();
}
arb_exp(t, w1, prec1);
arb_mul(t, t, w1, prec1);
if (!arb_contains(t, x1))
{
flint_printf("FAIL: functional equation\n\n");
flint_printf("branch = %d, prec1 = %wd, prec2 = %wd\n\n", branch, prec1, prec2);
flint_printf("x1 = "); arb_printd(x1, 50); flint_printf("\n\n");
flint_printf("x2 = "); arb_printd(x2, 50); flint_printf("\n\n");
flint_printf("w1 = "); arb_printd(w1, 50); flint_printf("\n\n");
flint_printf("w2 = "); arb_printd(w2, 50); flint_printf("\n\n");
flint_printf("t = "); arb_printd(t, 50); flint_printf("\n\n");
flint_abort();
}
arb_clear(x1);
arb_clear(x2);
arb_clear(t);
arb_clear(w1);
arb_clear(w2);
}
TEST_FUNCTION_END(state);
}