Opened 8 years ago
Closed 21 months ago
#14068 closed defect (fixed)
nauty_geng is naughty
| Reported by: | azi | Owned by: | jason, ncohen, rlm |
|---|---|---|---|
| Priority: | major | Milestone: | sage-9.0 |
| Component: | graph theory | Keywords: | |
| Cc: | dimpase | Merged in: | |
| Authors: | David Coudert, Dima Pasechnik | Reviewers: | Dima Pasechnik |
| Report Upstream: | N/A | Work issues: | |
| Branch: | 93edfb0 (Commits, GitHub, GitLab) | Commit: | 93edfb05921b4fba999b9eda0c7f128d99be1f36 |
| Dependencies: | Stopgaps: |
Status badges
Description (last modified by )
I think nauty_geng should not ignore geng's return value and return an exception if the returned value is not 0. Consider the following:
def find_counterexample(n):
for G in graphs.nauty_geng("-c" + str(n)):
if is_counterexample(G):
print 'Yeees, there is a counterexample'
return
print 'No counterexamples! Conjecture holds'
the code appears to be just fine but it has a bug! Namely it tries to run the program geng with the parameter "-cn" instead of "-c n". Hence geng returns an error and instead of getting an error in Sage, it simply does not generate any graphs.
The branch implements the catching of geng's error. We also clean up the code of graph_generators a bit.
Change History (14)
comment:1 Changed 8 years ago by
- Cc changed from rbeezer,ncohen, dcoudert to rbeezer, ncohen, dcoudert
- Milestone changed from sage-5.11 to sage-5.12
comment:2 Changed 7 years ago by
- Milestone changed from sage-6.1 to sage-6.2
comment:3 Changed 7 years ago by
- Milestone changed from sage-6.2 to sage-6.3
comment:4 Changed 7 years ago by
- Milestone changed from sage-6.3 to sage-6.4
comment:5 Changed 21 months ago by
- Branch set to public/graphs/14068_nauty
- Commit set to 759fab2f8961aa5ab7e6d5e57ac96f9625f70080
- Milestone changed from sage-6.4 to sage-8.9
- Status changed from new to needs_review
comment:6 follow-up: ↓ 8 Changed 21 months ago by
I don't understand the reported pyflakes error with sage.graphs.strongly_regular_db. Other modules are imported the same way without causing pyflakes errors.
comment:7 Changed 21 months ago by
- Cc dimpase added; rbeezer ncohen dcoudert removed
comment:8 in reply to: ↑ 6 Changed 21 months ago by
Replying to dcoudert:
I don't understand the reported pyflakes error with
sage.graphs.strongly_regular_db. Other modules are imported the same way without causing pyflakes errors.
perhaps pyflakes is confused by staticmethod() thing.
The only place where a method from strongly_regular_db is used is
strongly_regular_graph = staticmethod(sage.graphs.strongly_regular_db.strongly_regular_graph)
by the way, I don't understand why it's not written as
from . import strongly_regular_db ... strongly_regular_graph = staticmethod(strongly_regular_db.strongly_regular_graph)
Is it cause this code pre-dates from . syntax?
comment:9 Changed 21 months ago by
- Commit changed from 759fab2f8961aa5ab7e6d5e57ac96f9625f70080 to 93edfb05921b4fba999b9eda0c7f128d99be1f36
Branch pushed to git repo; I updated commit sha1. New commits:
| 93edfb0 | refactoring using 'from .' syntax
|
comment:10 Changed 21 months ago by
OK, otherwise looks good. let's see if this commit makes pyflakes happy
comment:11 Changed 21 months ago by
pyflakes is now happy !
comment:12 Changed 21 months ago by
- Description modified (diff)
- Reviewers set to Dima Pasechnik
- Status changed from needs_review to positive_review
comment:13 Changed 21 months ago by
- Milestone changed from sage-8.9 to sage-9.0
moving milestone to 9.0 (after release of 8.9)
comment:14 Changed 21 months ago by
- Branch changed from public/graphs/14068_nauty to 93edfb05921b4fba999b9eda0c7f128d99be1f36
- Resolution set to fixed
- Status changed from positive_review to closed
A possible fix is to raise an error only when parameter debug is False and that something goes wrong.
When debug is True, the behavior remains the same as before and so we continue to display the message output by geng in stderr.
New commits:
trac #14068: check input when debug is False