Add Hankel functions and make spherical Bessel and Hankel functions symbolic

[eviatarbach]

For some reason Sage has spherical Hankel functions but not regular ones. This patch adds Hankel functions and makes spherical Hankel and Bessel functions symbolic, as well as adding arbitrary-precision numeric evaluation.

Depends on #18257

CC: @burcin @fchapoton @paulmasson

Component: symbolics

Author: Eviatar Bach, Ralf Stephan

Branch/Commit: 7e48705

Reviewer: Paul Masson

Issue created by migration from https://trac.sagemath.org/ticket/15024

[eviatarbach]

Attachment: trac15024.patch.gz

[eviatarbach]

comment:1

Note that this also changes the LaTeX representation for the other Bessel functions by removing \operatorname, since in all sources I've seen the function name is italicized.

Patchbot apply trac15024.patch

[eviatarbach]

comment:2

New patch gets coverage to 100%, adds _latex_ methods (for getting a LaTeX representation for the function without arguments), and adds \left and \right to _print_latex_, which I forgot before.

Patchbot apply trac15024_2.patch

[sagetrac-vbraun-spam]

comment:3

Attachment: trac15024_2.patch.gz

[kcrisman]

comment:4

Note also the Struve functions

struve_h (v,z)                 Struve H function
struve_l (v,z)                 Struve L function

noted at the symbolics wiki on Trac, which seem to go with the Hankels...

[eviatarbach]

comment:5

Yeah, those should be easy to add, although maybe in another ticket.

[kcrisman]

comment:6

Sure, this is #16221 now. By the way, do we really want the Hankel stuff in bessel.py?