Hi, > 1) I am looking for the definitions of graph operations such as > intersection, union, etc., but could not find them in the API > documentation. Is there any place where I can find their definitions? In cases when the documentation of the Python interface is not detailed enough, you can try to find the corresponding functions in the documentation of the C core:
http://igraph.org/c/doc/igraph-Operators.html Although, to be honest, it seems that the documentation of the C core is not too verbose either. Let me know if you need more information about these operators. > 2) I tried to glean out the current state of augmenting attributes to > edges when adding them through add_edges() from the mailing list > archives, but could not. I understand this is possible when using > add_edge(), but it is clear from the authors' replies that add_edges() > is much more faster. Unfortunately this is not supported directly by add_edges() yet, but you can create a helper function like: def better_add_edges(graph, es, **kwds): m = graph.ecount() graph.add_edges(es) for attr_name, values in kwds.iteritems(): graph.es[m:][attr_name] = values (If you use igraph from Python 3.x, use kwds.items() instead of kwds.iteritems()) Then you can do something like this: better_add_edges(graph, [(2,3), (2,4)], weight=[21,42], color=["red", "green"]) Actually, this is probably what the "real" imlpementation of add_edges() would do if it weren't for me being too lazy to add it in the first place ;) Best, Tamas _______________________________________________ igraph-help mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/igraph-help
