Attributes in the linegraph function

Usage
1

I am currently looking into the differences between the linegraph() function compared to a one-node-projection in a bipartite graph and was wondering, if there was a way to conserve the edge attributes and move them to the vertices using the igraph.GraphBase.linegraph() function?

2

You can copy the attributes manually with something like:

lg = g.linegraph()
for attr in g.edge_attributes():
    lg.vs[attr] = g.es[attr]

You are welcome to submit a feature request to preserve vertex attributes, but please discuss realistic use cases in detail.

3

Thank you very much for the input.

I wasn’t sure the indexing would be preserved. This should solve my problem and I will think a bit about the use cases.

4

Good point. We will document that it is preserved.

1 Like
5

I should point out that when the python-igraph documentation is sparse on details, it’s usually worth checking the C documentation, which tends to give more details:

https://igraph.org/c/html/latest/igraph-Operators.html#igraph_linegraph

I have now updated the python-igraph docs with this information.