On 2014-02-24, Marc Mezzarobba <[email protected]> wrote: > Hi Dror, > > dror fidler wrote: >> i recently used is_distance_regular() in the graph package. >> however the definition of the function in the documentation page does >> not fit the definition of distance regular graphs. i would be very >> interested to find the source of the information the author used for >> this alternative definition. the wikipedia page they refer to does not >> trivially show this relation. > > To find who added some particular piece of code to Sage, use "git blame" > on the file containing the code. In our case, > > $ git blame src/sage/graphs/distances_all_pairs.pyx > > reveals that is_distance_regular() was added by Nathann Cohen as part of > commit 4d84feb2a, implementing trac ticket #14619. > > You can then find more information on the ticket's page: > > http://trac.sagemath.org/ticket/14619
I just checked this out, and I agree that the definition is not right. With such a definition e.g. every vertex-transitive graph is distance-regular, and this is clearly nonsense! I'll ping the author on the ticket... Dima > > Hope this helps, > > -- > Marc > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/groups/opt_out.
