Re: [sage-devel] Nauty as a default generator for graphs
On Fri, Mar 09, 2018 at 08:19:19AM +0200, Jori Mäntysalo wrote: > It is much faster to say sum(1 for _ in graphs.nauty_geng(7)) than sum(1 for > _ in graphs(7)), and after #19919 we have nauty as a standard package. > > Will I break something if I change graphs(n) without any additional > parameter to use nauty? A user really needing the old code could then say > graphs(n, property=lambda x: True). I think that Sage documentation makes no > promise at all about the order in which graphs are generated. I am all for it. Nauty is sooo much faster. In fact, I'd be glad if some of Nauty's arguments would be exposed, in particular to generate acyclic graphs, ... Cheers, Nicolas PS: +1 as well to Graphs(10), in particular to provide an easy access point for computing the number of graphs using Pólya enumeration. Yes, we need to settle for a definition of containment, but that should not be too hard. -- Nicolas M. Thiéry "Isil" http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Nauty as a default generator for graphs
On Fri, 9 Mar 2018, David Roe wrote: Will I break something if I change graphs(n) without any additional parameter to use nauty? It did the change at https://trac.sagemath.org/ticket/24951 Sounds good to me. You might add an algorithm keyword to the graphs function, which defaults to nauty. Not sure... It can be done with property=lambda _: True. I think that mostly algorithm-keyword should have a meaning -- there should be a situation where someone would prefer one over the other. On Fri, 9 Mar 2018, 'Martin R' via sage-devel wrote: Besides, it would also be supercool to have a class Graphs analogous to the class Posets, and have the cardinality of the first few layers built in (analogous to Posets(16).cardinality()) I am not sure about that. What should be the meaning of, say "g in graphs(10)" or "g in graphs"? -- Jori Mäntysalo
Re: [sage-devel] Nauty as a default generator for graphs
On Fri, Mar 9, 2018 at 1:19 AM, Jori Mäntysalo wrote: > It is much faster to say sum(1 for _ in graphs.nauty_geng(7)) than sum(1 > for _ in graphs(7)), and after #19919 we have nauty as a standard package. > > Will I break something if I change graphs(n) without any additional > parameter to use nauty? A user really needing the old code could then say > graphs(n, property=lambda x: True). I think that Sage documentation makes > no promise at all about the order in which graphs are generated. Sounds good to me. You might add an algorithm keyword to the graphs function, which defaults to nauty. David > > > -- > Jori Mäntysalo > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Nauty as a default generator for graphs
It is much faster to say sum(1 for _ in graphs.nauty_geng(7)) than sum(1 for _ in graphs(7)), and after #19919 we have nauty as a standard package. Will I break something if I change graphs(n) without any additional parameter to use nauty? A user really needing the old code could then say graphs(n, property=lambda x: True). I think that Sage documentation makes no promise at all about the order in which graphs are generated. -- Jori Mäntysalo