Opened 3 years ago
Closed 3 years ago
#19180 closed enhancement (fixed)
A (220,84,38,28)strongly regular graph
Reported by:  ncohen  Owned by:  

Priority:  major  Milestone:  sage6.9 
Component:  graph theory  Keywords:  
Cc:  dimpase  Merged in:  
Authors:  Nathann Cohen  Reviewers:  Dima Pasechnik 
Report Upstream:  N/A  Work issues:  
Branch:  6ce1899 (Commits)  Commit:  6ce189941a6a7d63f0fd100ef3cc8c680483c1f0 
Dependencies:  #19133  Stopgaps: 
Description
A new graph to be added to our collection.
Nathann
Change History (10)
comment:1 Changed 3 years ago by
 Branch set to public/19180
 Commit set to d9be4b94f02e6cb0ce6335025916098c2c0e770f
 Status changed from new to needs_review
comment:2 Changed 3 years ago by
 Commit changed from d9be4b94f02e6cb0ce6335025916098c2c0e770f to 7cbfa8b1425fccb6ca404a6f72f253b5ccf99eeb
Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:
7cbfa8b  trac #19180: A (220,84,38,28)strongly regular graph

comment:3 followup: ↓ 5 Changed 3 years ago by
You mentioned (on https://groups.google.com/forum/#!topic/sagesupport/dPG73HQZKY) that the function takes 40s. I don't have time right now to check out the ticket and compile and test, but I get
sage: %timeit L = [ w for w in codes.ExtendedQuadraticResidueCode(47,GF(2)) if w.hamming_weight() == 12 ] 1 loops, best of 3: 16.4 s per loop
By the way, glancing through your code, you should probably use hamming_weight
and not sum
to determine the hamming weight. Sum could (should?) behave as over GF(2)
in something like this code.
comment:4 followup: ↓ 7 Changed 3 years ago by
Pretty awesome way you compacted and cached the results, btw :)
comment:5 in reply to: ↑ 3 Changed 3 years ago by
By the way, glancing through your code, you should probably use
hamming_weight
Right, it is faster indeed. It now takes ~12s. hamming_weight
does the job at a much lower level.
and not
sum
to determine the hamming weight. Sum could (should?) behave as overGF(2)
in something like this code.
I apply it to ints, not to GF(2)
elements.
Thanks,
Nathann
comment:6 Changed 3 years ago by
 Commit changed from 7cbfa8b1425fccb6ca404a6f72f253b5ccf99eeb to 6ce189941a6a7d63f0fd100ef3cc8c680483c1f0
Branch pushed to git repo; I updated commit sha1. New commits:
6ce1899  trac #19180: Speedup

comment:7 in reply to: ↑ 4 Changed 3 years ago by
Pretty awesome way you compacted and cached the results, btw :)
The first version was in base 10, but I know Dima does not like to see long lists like that. So I tried to make it a bit smaller :P
Nathann
comment:8 Changed 3 years ago by
 Reviewers set to Dima Pasechnik
 Status changed from needs_review to positive_review
looks good to me.
comment:9 Changed 3 years ago by
Thaaaaaaaaaaaaaanks !!!
comment:10 Changed 3 years ago by
 Branch changed from public/19180 to 6ce189941a6a7d63f0fd100ef3cc8c680483c1f0
 Resolution set to fixed
 Status changed from positive_review to closed
New commits:
trac #19133: Three Wittbased strongly regular graphs
trac #19133: Merged with 6.9.beta5
trac #19133: Broken doctests
trac #19180: A (220,84,38,28)strongly regular graph