pub(crate) fn spherical_hankels(
first: u32,
last: u32,
z: Complex,
) -> Result<Vec<Complex>>Expand description
Spherical Hankel functions h_p(z) of the first kind for p = first..=last at a
nonzero argument. Real positive arguments use the elementary outgoing seed and
upward recurrence (DLMF 10.49.6, 10.51.1). Unlike regular J, H contains the dominant
irregular solution, so this direction is stable below the turning point too.
The bounded domain keeps every intermediate finite and agrees with AMOS to the
existing 1e-13 sequence tolerance; other arguments retain one AMOS sequence.