void
arb_max(arb_t z, const arb_t x, const arb_t y, slong prec)
{
arf_t left, right, t, xr, yr;
if (arf_is_nan(arb_midref(x)) || arf_is_nan(arb_midref(y)))
{
arb_indeterminate(z);
return;
}
arf_init(left);
arf_init(right);
arf_init(t);
arf_init_set_mag_shallow(xr, arb_radref(x));
arf_init_set_mag_shallow(yr, arb_radref(y));
arf_sub(left, arb_midref(x), xr, prec, ARF_RND_FLOOR);
arf_sub(t, arb_midref(y), yr, prec, ARF_RND_FLOOR);
arf_max(left, left, t);
arf_add(right, arb_midref(x), xr, prec, ARF_RND_CEIL);
arf_add(t, arb_midref(y), yr, prec, ARF_RND_CEIL);
arf_max(right, right, t);
arb_set_interval_arf(z, left, right, prec);
arf_clear(left);
arf_clear(right);
arf_clear(t);
}
/* sample (x, y) so that x /in y */
void _sample_arf_in_arb(arf_t x, arb_t y, flint_rand_t state)
{
slong bits, prec, expbits;
arf_t a, b;
slong i, n;
arf_init(a);
arf_init(b);
bits = 2 + n_randint(state, 1000);
prec = 2 + n_randint(state, 1000);
expbits = n_randint(state, 14);
n = n_randint(state, 3);
arf_randtest(x, state, bits, expbits);
arf_set(a, x);
arf_set(b, x);
for (i = 0; i < n; i++)
{
arf_randtest(x, state, bits, expbits);
arf_min(a, a, x);
arf_max(b, b, x);
}
arb_set_interval_arf(y, a, b, prec);
arf_clear(a);
arf_clear(b);
}