longer paths in metapath2vec

[nabihach]

I'm trying to use PyG's MetaPath2Vec and I have a question about this line:

pytorch_geometric/torch_geometric/nn/models/metapath2vec.py

Line 30 in 58eb6b4

:obj:`(source_node_type, relation_type, target_node_type)` tuples.

Why must each metapath be a 3-tuple? How can I specify longer metapaths, e.g. a metapath which has 5 items node_A --> Link A_A -> node_B --> link B_C --> node_C?

[rusty1s]

Yes, that is well possible. Note that metapath is a list of tuples, e.g.:

[
    (author, writes, paper),
    (paper, cites, paper),
    (paper, written_by, author),
    ...
]

[nabihach]

I see, so the tuples together specify one metapath.
My follow-up question would be, how do I specify more than 1 metapaths?

[rusty1s]

That is not possible. Does the original metapath2vec model provide this functionality?

[nabihach]

Reading the paper again, I now realize it only uses a single metapath at a time. Thanks for answering and clearing it up!