I have generated an extremely large list of graphs. Do you know if there is a way to determine which graphs in the list are Complete Bipartite graphs? I have tried a filter function: dd = filter(lambda x:x.completebipatitegraphs(), d), but it gives me an "attribute needed" error. Any help is greatly appreciated!
You can use the following function to test if a graph is complete bipartite:
def is_complete_bipartite(p):
return p.is_bipartite() and p.num_edges() == mul(map(len, p.bipartite_sets()))
Then, you can do
dd = filter(is_complete_bipartite, d)
to get your list of complete bipartites.
in case you want to practice writing lambdas, you can do
dd=filter(lambda p: p.is_bipartite() and p.num_edges() == mul(map(len, p.bipartite_sets())), d)
I have been reading the Sage References, and it does not seem that complete multipartite graphs are defined in Sage yet. I have tried to critique the code you have provide to try and see if it would work for complete multipartite graphs. I get a "graph attribute needed" error. I just wanted to verify that this is the case. Thanks again for the help!
Asked: 2011-08-30 11:56:35 +0100
Seen: 681 times
Last updated: Sep 04 '11
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