Add (symbolic) Struve functions

[kcrisman]

Apparently Maxima has this.

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

See #15024 and the symbolic wiki on Trac for more detail.

Component: symbolics

Keywords: special, holonomic

Author: Ralf Stephan

Branch/Commit: cf92ce3

Reviewer: Karl-Dieter Crisman, Frédéric Chapoton

Issue created by migration from https://trac.sagemath.org/ticket/16221

[rwst]

Branch: u/rws/add__symbolic__struve_functions

[rwst]

Author: Ralf Stephan

[rwst]

Changed keywords from none to special, holonomic

[rwst]

Commit: 03e076a

[rwst]

New commits:

03e076a

16221: implement Struve H/L functions

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

a6a6310

Merge branch 'develop' into t/16221/add__symbolic__struve_functions

[sagetrac-git]

Changed commit from 03e076a to a6a6310

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

8b4b908	Merge branch 'develop' into t/16221/add__symbolic__struve_functions
e7ad2ee	16221: simplification due to improved BuiltinFunction; better doctests

[sagetrac-git]

Changed commit from a6a6310 to e7ad2ee

[kcrisman]

Reviewer: Karl-Dieter Crisman

[kcrisman]

comment:7

Comments, putting 'needs info' just so the status is clear.

• Think we should implement A&S 12.1.15 or 12.2.10?
• This

sage: struve_L(i.n(),100)
1.07916123209824e42 + 4.90584803419713e22*I

doesn't seem to agree with W|A, though I don't know whether it should even be implemented.

• W functions claims something that isn't in A&S but that certainly works with mpmath:

sage: struve_H(-2,0)
struve_H(-2, 0)
sage: struve_H(-3,0)
struve_H(-3, 0)
sage: struve_H(-3,0).n()
0.000000000000000
sage: struve_H(-2,0).n()
0.000000000000000
sage: struve_H(-7/2,0)
struve_H(-7/2, 0)
sage: struve_H(-7/2,0).n()
0.000000000000000

• Maybe doctest at least a couple of the interfaces, at least with mpmath and Maxima? (I don't know if Maxima returns any of these when you plug in this particular DE, but if it did that would be perfect.)

Otherwise I think this is definitely ready to get in, and a useful addition!

[kcrisman]

comment:8

One more thing - just like in #15024, probably there should be a little top-matter added, just for completeness.

[kcrisman]

comment:9

(Interestingly, #18257 doesn't seem to afflict this one - maybe it didn't add as many functions as #15024.)

[rwst]

Changed branch from u/rws/add__symbolic__struve_functions to u/rws/16221

[rwst]

comment:12

That should do it. Could you please have a final glance?

---

New commits:

34c4d1e

16221: Struve functions

[rwst]

Changed commit from e7ad2ee to 34c4d1e

[rwst]

Changed branch from u/rws/16221 to u/rws/16221-1

[fchapoton]

comment:17

doc of _print_latex_ is not formatted correctly (twice)

REFERENCE blocks are not formatted correctly either.

[sagetrac-git]

Changed commit from faf5fd5 to fbb6999

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

2980d87	Merge branch 'u/rws/16221-1' of git://trac.sagemath.org/sage into tmp05
fbb6999	16221: fix doc refs and formatting

[fchapoton]

comment:20

doc does not build: duplicate citation ASHandbook

[sagetrac-git]

Changed commit from fbb6999 to cf92ce3

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

cf92ce3

16221: complete references

[rwst]

comment:22

The references in functions/ need some love in general.

[fchapoton]

comment:23

ok, let it be

[fchapoton]

Changed reviewer from Karl-Dieter Crisman to Karl-Dieter Crisman, Frédéric Chapoton

[rwst]

comment:24

Thanks for the review!

[vbraun]

Changed branch from u/rws/16221-1 to cf92ce3