bind SymPy's ComplexInfinity

[rwst]

sage: import sympy
sage: SR(sympy.factorial(-2))
---------------------------------------------------------------------------
...
AttributeError: 'ComplexInfinity' object has no attribute '_sage_'

Depends on #20185

Component: interfaces

Keywords: unsigned infinity

Author: Ralf Stephan

Branch/Commit: 0ef8018

Reviewer: Karl-Dieter Crisman, Marc Mezzarobba

Issue created by migration from https://trac.sagemath.org/ticket/17493

[rwst]

Branch: u/rws/bind_sympy_s_complexinfinity

[rwst]

Commit: 3dccb4e

[rwst]

comment:2

That would be all. However, I have no idea atm how to change sympify to convert to zoo. EDIT. it's not zoo, it's Infinity as well.

---

New commits:

3dccb4e

17493: add `_sage_` method to ComplexInfinity

[rwst]

Author: Ralf Stephan

[sagetrac-git]

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

7ca600a

17493: doctest

[sagetrac-git]

Changed commit from 3dccb4e to 7ca600a

[sagetrac-git]

Changed commit from 7ca600a to 4928fa4

[sagetrac-git]

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

4928fa4

17493: remove unrelated patchfile

[rwst]

Changed keywords from none to unsigned infinity

[kcrisman]

comment:6

How does this one relate to #14723? I assume this is also part of your large upstream patch? I guess in principle this one can just depend on #14723 since the .p1 is correct if that one is .p0.

[kcrisman]

Upstream: Not yet reported upstream; Will do shortly.

[rwst]

Dependencies: #14723

[rwst]

Changed upstream from Not yet reported upstream; Will do shortly. to Completely fixed; Fix reported upstream

[rwst]

comment:7

Replying to @kcrisman:

How does this one relate to #14723? I assume this is also part of your large upstream patch? I guess in principle this one can just depend on #14723 since the .p1 is correct if that one is .p0.

Yes and yes. Github pull request: sympy/sympy#8592

[kcrisman]

comment:8

I have to say I'm totally mystified as to why this is called zoo. Is this a pun?

Here is something we might as well take care of here. But the change here itself is fine and useful.

sage: a = oo
sage: b = -oo
sage: c = UnsignedInfinityRing.gen()  
# really, the easiest way?  probably should do better than that, not here
sage: a
+Infinity
sage: b
-Infinity
sage: c
Infinity
sage: a._sympy_()
oo
sage: b._sympy_()
-oo
sage: c._sympy_()
---------------------------------------------------------------------------
AttributeError: 'UnsignedInfinity' object has no attribute '_sympy_'

A nice test for that would be

gamma(-3)._sympy_() is sympy.factorial(-2)
gamma(-3) is sympy.factorial(-2)._sage_()

(note that putting it in SR makes it == but not is).

[kcrisman]

Reviewer: Karl-Dieter Crisman

[kcrisman]

comment:9

We really should have both directions on this ticket, I think.

[sagetrac-git]

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

1aff5f2	Merge branch 'develop' into t/17493/bind_sympy_s_complexinfinity
27e2fc7	17493: add unsigned_infinity conversion to sympy

[sagetrac-git]

Changed commit from 4928fa4 to 27e2fc7

[rwst]

comment:11

Ah it was easier than thought.

[kcrisman]

comment:12

Ah it was easier than thought.

That's why I asked, otherwise it would have been a separate ticket for sure. I'll get to this today for sure.

[mezzarobba]

comment:14

Conflicts with #14723

[rwst]

comment:15

Resolved in #14723.

[vbraun]

comment:21

Sorry, misunderstood the last comment.

Whats up with the dependency?

PSA: sage-pending tickets are not getting merged

[rwst]

comment:22

The dependency is pending (because there is still no new SymPy release---0.7.6.1 is just a quick fix of Jupyter stuff) so this is pending, too.

[rwst]

Changed branch from u/kcrisman/ticket/17493 to public/17493

[rwst]

Changed commit from a514394 to 0ef8018

[rwst]

New commits:

f89b9e8	Merge branch 'u/kcrisman/ticket/17493' of git://trac.sagemath.org/sage into i17493
0ef8018	remove now unnecessary patch

[rwst]

Changed upstream from Completely fixed; Fix reported upstream to none

[rwst]

Changed dependencies from #14723 to #20185

[mezzarobba]

Changed reviewer from Karl-Dieter Crisman to Karl-Dieter Crisman, Marc Mezzarobba

[vbraun]

Changed branch from public/17493 to 0ef8018