Argument, x >= 0 (NaN for negative x; -Infinity at 0).
Order, any real number. For nu < 0, Y(x, -nu) = sin(pi nu) J(x, nu) + cos(pi nu) Y(x, nu)
(A&S 9.1.2, as in R).
Y_nu(x).
For orders above 1000, results far out of the range of doubles are returned at once (Infinity or 0, decided by
bounds on their log); otherwise the time grows with the order (a recurrence of about nu steps): about 2.4 s for
besselY(0.9e8, 1e8). Beyond 2^28 steps, or 2^25 terms of the continued fraction for x above nu (as for
besselJ), a RangeError is thrown before the computation, and likewise for a phase correction nu^2 / (2x)
beyond 2^26 in the asymptotic expansion for large x.
Bessel function of the second kind. Equivalent to R's
besselY(x, nu). Takes single numbers.