[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

Craig Citro wrote: >>> There is such a search right here: >>> >>>http://groups..google.com/group/sage-devel >>> >> >> Yes. I meant "I love that Sage has a google search. I wish the nauty >> list had a google search, but I can't seem to find any sea

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

>> There is such a search right here: >> >>    http://groups..google.com/group/sage-devel >> > > > Yes.  I meant "I love that Sage has a google search.  I wish the nauty > list had a google search, but I can't seem to find any search for their > archives

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

William Stein wrote: > > > On Thu, Jul 30, 2009 at 10:26 AM, Jason Grout > mailto:jason-s...@creativetrax.com>> wrote: > > > William Stein wrote: > > > > > > On Thu, Jul 30, 2009 at 10:02 AM, Jason Grout > > mailto:jason-s...@creativetrax.com> >

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Jul 30, 9:51 am, Nathann Cohen wrote: > Wonderful ! It was just a mistake coming from my own code ( please > accept my apologies ! ). The coloring it now returns is : > [[5, 1, 2], [7, 6, 3], [9, 0], [8, 4]] That works. ;-) No apologies needed - it is good to get bugs squashed early in the

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

There's a lot of data out there in graph6 format (e.g. Gordon Royle's collections) so it is good that Sage supports it (and should continue to do so). This would certainly cause pain if there was a movement for any kind of wholesale conversion.But for Trac, cut/paste, doctests, etc, etc, I th

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Thu, Jul 30, 2009 at 10:31 AM, Jason Grout wrote: > > Rob Beezer wrote: > > On Jul 30, 10:04 am, William Stein wrote: > >> What did he say? I've only seen him speak on the History Channel > >> (seriously). > > > > LOL. Topic is now graph codes, not Bible Codes. > > > > I think graph7 would b

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

Rob Beezer wrote: > On Jul 30, 10:04 am, William Stein wrote: >> What did he say? I've only seen him speak on the History Channel >> (seriously). > > LOL. Topic is now graph codes, not Bible Codes. > > I think graph7 would be worse since then we'd have 7 bits to a > character and more bad cha

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Thu, Jul 30, 2009 at 10:26 AM, Jason Grout wrote: > > William Stein wrote: > > > > > > On Thu, Jul 30, 2009 at 10:02 AM, Jason Grout > > mailto:jason-s...@creativetrax.com>> > wrote: > > > > > > Robert Miller wrote: > > > On Thu, Jul 30, 2009 at 9:27 AM, Rob > > Beezermailto:goo...

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

William Stein wrote: > > > On Thu, Jul 30, 2009 at 10:02 AM, Jason Grout > mailto:jason-s...@creativetrax.com>> wrote: > > > Robert Miller wrote: > > On Thu, Jul 30, 2009 at 9:27 AM, Rob > Beezermailto:goo...@beezer.cotse.net>> wrote: > >> As an aside, maybe the graph6 forma

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

William Stein wrote: > > > On Thu, Jul 30, 2009 at 9:38 AM, Robert Miller > wrote: > > > On Thu, Jul 30, 2009 at 9:27 AM, Rob Beezer > wrote: > > > > As an aside, maybe the graph6 format doesn't work so well in >

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Jul 30, 10:04 am, William Stein wrote: > What did he say?  I've only seen him speak on the History Channel > (seriously). LOL. Topic is now graph codes, not Bible Codes. I think graph7 would be worse since then we'd have 7 bits to a character and more bad characters. Maybe graph5? But ser

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Thu, Jul 30, 2009 at 10:02 AM, Jason Grout wrote: > > Robert Miller wrote: > > On Thu, Jul 30, 2009 at 9:27 AM, Rob Beezer > wrote: > >> As an aside, maybe the graph6 format doesn't work so well in Trac? The > >> back-ticks seem to have disappeared, leading to quite a different > >> graph. ;-)

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

Robert Miller wrote: > On Thu, Jul 30, 2009 at 9:27 AM, Rob Beezer wrote: >> As an aside, maybe the graph6 format doesn't work so well in Trac? The >> back-ticks seem to have disappeared, leading to quite a different >> graph. ;-) > > Never trust graph6 string conversion -- almost every bad char

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Thu, Jul 30, 2009 at 9:38 AM, Robert Miller wrote: > > On Thu, Jul 30, 2009 at 9:27 AM, Rob Beezer > wrote: > > > > As an aside, maybe the graph6 format doesn't work so well in Trac? The > > back-ticks seem to have disappeared, leading to quite a different > > graph. ;-) > > Never trust graph

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

Wonderful ! It was just a mistake coming from my own code ( please accept my apologies ! ). The coloring it now returns is : [[5, 1, 2], [7, 6, 3], [9, 0], [8, 4]] Which is a partition into stable sets ( no repeated element, no missing one ).. and is of cardinal 4 ! ;-) Thank you for your help,

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

Ooops, then it is another of my mistakes... I'm checking and I tell you ;-) Thanks !!! On Jul 30, 6:38 pm, Robert Miller wrote: > On Thu, Jul 30, 2009 at 9:27 AM, Rob Beezer wrote: > > > As an aside, maybe the graph6 format doesn't work so well in Trac? The > > back-ticks seem to have disappear

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Thu, Jul 30, 2009 at 9:27 AM, Rob Beezer wrote: > > As an aside, maybe the graph6 format doesn't work so well in Trac? The > back-ticks seem to have disappeared, leading to quite a different > graph.  ;-) Never trust graph6 string conversion -- almost every bad character is legal! > Rob --

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Jul 30, 5:41 am, Nathann Cohen wrote: > Trying to write a Linear Program version of the coloring problem, I > found a graph ( pure luck, it was a RandomGNP ) for which the > functions chromatic_number() and coloring() return a wrong value. > > sage: h=Graph(":I`ASWCaG`WaJC{afP") > sage: h.chro

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

The graph is defined in the previous message ! ;-) sage: h=Graph(":I`ASWCaG`WaJC{afP") You can obtain a string describing a graph by using the Graph.graph6_string method. Pretty useful ! And this ticket you mentionned is there : http://trac.sagemath.org/sage_trac/ticket/6660 ;-) Nathann This

[sage-devel] Re: Error in Graph.chromatic_number() and Graph.coloring()

On Jul 30, 2009, at 5:41 AM, Nathann Cohen wrote: > > Hello !! > > Trying to write a Linear Program version of the coloring problem, I > found a graph ( pure luck, it was a RandomGNP ) for which the > functions chromatic_number() and coloring() return a wrong value. > > sage: h=Graph(":I`ASWCaG`W