jax.scipy.special.yn

Contents

jax.scipy.special.yn#

jax.scipy.special.yn(n, z)[source]#

Bessel function of the second kind of integer order n.

JAX implementation of scipy.special.yn.

\[Y_n(z) = -\frac{1}{\pi} \sum_{k=0}^{n-1} \frac{(n - k - 1)!}{k!} \left(\frac{z}{2}\right)^{2k - n} + \frac{2}{\pi} \ln\left(\frac{z}{2}\right) J_n(z) - \frac{1}{\pi} \sum_{k=0}^{\infty} \frac{\psi(k + 1) + \psi(n + k + 1)}{k!\,(n + k)!} \left(-\frac{z^2}{4}\right)^k \left(\frac{z}{2}\right)^n\]

for integer order \(n \ge 0\) (with \(Y_{-n}(z) = (-1)^n Y_n(z)\)).

Parameters:
  • n (int) – The integer order of the Bessel function (must be a static integer).

  • z (ArrayLike) – The argument(s) at which to evaluate \(Y_n(z)\). Real and complex inputs are supported.

Returns:

An array containing the evaluated Bessel function values.

Return type:

Array

Notes

Unlike scipy.special.yn, jax.scipy.special.yn requires n to be a concrete integer order (so n cannot be traced or batched with jax.vmap()), and supports complex inputs directly (matching scipy.special.yv on the complex plane).