A bit more explanation of FPSim2Engine.substructure

[PatWalters]

First, thank you for a very helpful piece of code.

Second, could someone provide a bit more explanation for the FPSim2Engine.substructure function? I'm a bit confused by the search results. An example would be very helpful.

Thanks!

[eloyfelix]

Sorry for the very late reply — this one slipped through the cracks.

That kind of search is actually running a Tversky substructure screenout (as documented in the docs). It does not perform the subgraph isomorphism step on the candidates — it simply returns them. Because of that, you’ll see false positives compared to a strict substructure match.