[Lemon-user] Nauty reader / subgraphs

[Gwenaël Joret]

Dear all,

I recently had a look at the latest version of Lemon (0.7) and have
two unrelated questions.

1. I played a bit with the Nauty reader function. It seems that,
whatever the input graph is (in graph6 format, from the geng program),
the graph produced by the readNauty() function is always a complete
graph. Is it a known issue (or a problem on my side)?

2. I have some trouble figuring out how to handle subgraphs of a
graph. The following situation best illustrates my problem: Say f() is
some function taking a ListUGraph as a parameter, G is a ListUGraph,
and I want to call f() on some subgraph H of G.  Looking at Lemon's
documentation, it seems that the natural way to get H from G is to use
a SubUGraphAdaptor (or one of its variants). But then, I cannot call
f() on H, because H is not of ListUGraph type. Any clue?  (I am even
ready to make a whole copy of G and remove the extra nodes and edges,
but it appears that one cannot delete a node/edge from a ListUGraph.)

Best,
Gwenael