Opened 22 months ago
Closed 18 months ago
#30346 closed defect (fixed)
Exception for the unknot in Homfly-PT polynomial
Reported by: | soehms | Owned by: | |
---|---|---|---|
Priority: | major | Milestone: | sage-9.3 |
Component: | algebraic topology | Keywords: | link, knot, homfly |
Cc: | mmarco | Merged in: | |
Authors: | Sebastian Oehms | Reviewers: | Samuel Lelièvre |
Report Upstream: | N/A | Work issues: | |
Branch: | da6e768 (Commits, GitHub, GitLab) | Commit: | da6e768ffde18db3137a0cde1ee23aed08debec8 |
Dependencies: | Stopgaps: |
Description (last modified by )
Define the trivial link:
sage: L = Link([]); L Link with 1 component represented by 0 crossings
Before this ticket:
sage: L.homfly_polynomial() Traceback (most recent call last): ... SignalError: Bus error
After this ticket:
sage: L.homfly_polynomial() 1
Change History (10)
comment:1 Changed 22 months ago by
- Branch set to u/soehms/homfly_unknot
comment:2 Changed 22 months ago by
- Cc mmarco added
- Commit set to da6e768ffde18db3137a0cde1ee23aed08debec8
- Status changed from new to needs_review
comment:3 follow-up: ↓ 4 Changed 22 months ago by
Thanks for catching this. It would need a doctest.
Also, the unknot (or rather, the trivial diagram) is such a special case that i wouldn't be surprised if other methods also failed with it. It would be worth checking more carefully.
comment:4 in reply to: ↑ 3 Changed 22 months ago by
Replying to mmarco:
Thanks for catching this. It would need a doctest.
What further doctest do you mean?
Also, the unknot (or rather, the trivial diagram) is such a special case that i wouldn't be surprised if other methods also failed with it. It would be worth checking more carefully.
I will pay attention to that during my further development of the KnotInfo? package!
comment:5 Changed 21 months ago by
- Description modified (diff)
- Reviewers set to Samuel Lelièvre
- Status changed from needs_review to positive_review
Thanks!
comment:6 Changed 21 months ago by
- Status changed from positive_review to needs_work
[dochtml] [knots ] /home/release/Sage/local/lib/python3.8/site-packages/sage/knots/link.py:docstring of sage.knots.link.Link:95: WARNING: Exception occurred in plotting link-3 [dochtml] [knots ] from /home/release/Sage/src/doc/en/reference/knots/sage/knots/link.rst: [dochtml] [knots ] Traceback (most recent call last): [dochtml] [knots ] File "/home/release/Sage/local/lib/python3.8/site-packages/matplotlib/sphinxext/plot_directive.py", line 472, in run_code [dochtml] [knots ] exec(code, ns) [dochtml] [knots ] File "<string>", line 2, in <module> [dochtml] [knots ] File "sage/structure/parent.pyx", line 900, in sage.structure.parent.Parent.__call__ (build/cythonized/sage/structure/parent.c:9337) [dochtml] [knots ] return mor._call_(x) [dochtml] [knots ] File "sage/structure/coerce_maps.pyx", line 161, in sage.structure.coerce_maps.DefaultConvertMap_unique._call_ (build/cythonized/sage/structure/coerce_maps.c:4623) [dochtml] [knots ] raise [dochtml] [knots ] File "sage/structure/coerce_maps.pyx", line 156, in sage.structure.coerce_maps.DefaultConvertMap_unique._call_ (build/cythonized/sage/structure/coerce_maps.c:4515) [dochtml] [knots ] return C._element_constructor(x) [dochtml] [knots ] File "/home/release/Sage/local/lib/python3.8/site-packages/sage/groups/braid.py", line 1581, in _element_constructor_ [dochtml] [knots ] return self.element_class(self, x) [dochtml] [knots ] File "/home/release/Sage/local/lib/python3.8/site-packages/sage/groups/finitely_presented.py", line 236, in __init__ [dochtml] [knots ] fp_family = parent.gap().Identity().FamilyObj() [dochtml] [knots ] File "sage/libs/gap/element.pyx", line 2679, in sage.libs.gap.element.GapElement_MethodProxy.__call__ (build/cythonized/sage/libs/gap/element.c:20845) [dochtml] [knots ] return GapElement_Function.__call__(self, self.first_argument) [dochtml] [knots ] File "sage/libs/gap/element.pyx", line 2525, in sage.libs.gap.element.GapElement_Function.__call__ (build/cythonized/sage/libs/gap/element.c:19781) [dochtml] [knots ] sig_on() [dochtml] [knots ] sage.libs.gap.util.GAPError: Error, no method found! Error, no 2nd choice method found for `OneMutable' on 1 arguments [dochtml] [knots ] /home/release/Sage/local/lib/python3.8/site-packages/sage/knots/link.py:docstring of sage.knots.link.Link:108: WARNING: Exception occurred in plotting link-4
comment:7 Changed 20 months ago by
comment:8 Changed 19 months ago by
- Milestone changed from sage-9.2 to sage-9.3
comment:9 Changed 18 months ago by
- Status changed from needs_work to positive_review
I cannot reproduce this error and I completely don't understand how this could be caused by the changes of that ticket which don't use braid groups.
It looks very similar to me as the issue I reported in this comment and which I detected on all of my facilities as an interference between the upgrade of the Gap version and the cysignals
package (see comment 76 and 96 of #29314)
So lets have a try with that again!
comment:10 Changed 18 months ago by
- Branch changed from u/soehms/homfly_unknot to da6e768ffde18db3137a0cde1ee23aed08debec8
- Resolution set to fixed
- Status changed from positive_review to closed
New commits:
30346: initial version