Opened 7 years ago
Closed 7 years ago
#15503 closed defect (fixed)
DegreeSequences(n) returns false positive
Reported by: | ppurka | Owned by: | |
---|---|---|---|
Priority: | major | Milestone: | sage-6.1 |
Component: | graph theory | Keywords: | |
Cc: | ncohen | Merged in: | |
Authors: | Nathann Cohen | Reviewers: | Punarbasu Purkayastha |
Report Upstream: | N/A | Work issues: | |
Branch: | u/ncohen/15503 (Commits, GitHub, GitLab) | Commit: | fd217a518be20b8dc0fcda19ed30cb4f8ba651c6 |
Dependencies: | Stopgaps: |
Description
From google spreadsheet which no one reads X-(
[2,2,2,2,1,1,1] in DegreeSequences(7)
returns "true."
Change History (14)
comment:1 follow-up: ↓ 3 Changed 7 years ago by
- Branch set to u/ncohen/15503
- Status changed from new to needs_review
comment:2 Changed 7 years ago by
- Commit set to fd217a518be20b8dc0fcda19ed30cb4f8ba651c6
Branch pushed to git repo; I updated commit sha1. New commits:
fd217a5 | trac #15503: DegreeSequences?(n) returns false positive |
comment:3 in reply to: ↑ 1 ; follow-up: ↓ 4 Changed 7 years ago by
Replying to ncohen:
Sorryyyyyyyyy
T_T
I forgot the first (and easiest) part of this theorem : the sum of all integers must be even. There even was a "S" variable equal to this sum that wasn't even ever used in the code
T_T
No idea what degree sequences mean :-/
What is google spreadsheet by the way ?
Open your sagenb notebook and on the top right you will see "Report a problem". That goes to a google form. And the bug report gets collected in this google spreadsheet (which no one reads).
comment:4 in reply to: ↑ 3 ; follow-up: ↓ 6 Changed 7 years ago by
No idea what degree sequences mean
:-/
Some graph stuff. It's fixed with this patch. You can review it yourself if you want, just notice that on wikipedia the "Erdos-Gallai" theorem begins by saying that the sum of the degrees must be even, and this is exactly what I had forgotten in this patch. Otherwise somebody will probably review it someday ^^;
What is google spreadsheet by the way ?
Open your sagenb notebook and on the top right you will see "Report a problem". That goes to a google form. And the bug report gets collected in this google spreadsheet (which no one reads).
...................... We have this amount of bug reports, and they are just rotting there ?....
T_T
Nathann
comment:5 Changed 7 years ago by
- Reviewers set to Punarbasu Purkayastha
- Status changed from needs_review to positive_review
Given the wikipedia definition, this patch looks correct to me.
EDIT: BTW, this passes all doctests in combinat/degree_sequences.pyx
, graphs/generators
and graphs/graph_generators.py
where the DegreeSequences
is used.
comment:6 in reply to: ↑ 4 Changed 7 years ago by
Replying to ncohen:
Open your sagenb notebook and on the top right you will see "Report a problem". That goes to a google form. And the bug report gets collected in this google spreadsheet (which no one reads).
...................... We have this amount of bug reports, and they are just rotting there ?....
Unfortunately, yes.
comment:7 Changed 7 years ago by
comment:8 follow-up: ↓ 9 Changed 7 years ago by
Oh. Can we remove lines from this spreadsheet once they have been translated into trac tickets ?
comment:9 in reply to: ↑ 8 Changed 7 years ago by
Replying to ncohen:
Oh. Can we remove lines from this spreadsheet once they have been translated into trac tickets ?
No idea which account that google spreadsheet belongs to. Perhaps you can ask on sage-devel.
comment:10 Changed 7 years ago by
Well we should definitely write about that... T_T
Do you ? Do I ?
Nathann
comment:11 Changed 7 years ago by
Go ahead. You can make a more dramatic mail than I can ;-)
That's probably a good thing in this case!
comment:12 Changed 7 years ago by
I'm always too dramatic (and aggressive). That's why I wanted too give the guys a rest :-PPP
comment:13 Changed 7 years ago by
Eek, I hope that degree sequence wasn't my fault five years ago...
Harald can give you write permissions on this document, guys. And I highly recommend putting some note in the "Comments" field I created a year or two ago that these are opened. If we were really on it we'd even respond to the emailers! Maybe I need to take a month and do this follow-up full time... except I have a day job.
comment:14 Changed 7 years ago by
- Resolution set to fixed
- Status changed from positive_review to closed
Sorryyyyyyyyy
T_T
I forgot the first (and easiest) part of this theorem : the sum of all integers must be even. There even was a "S" variable equal to this sum that wasn't even ever used in the code
T_T
What is google spreadsheet by the way ?
Nathann