[GAP Forum] labels in xgap

[William DeMeo]

Dear Forum,

Is it possible to change the labels of vertices in a subgroup lattice
drawn by XGAP using the command line (rather than using "Change
Labels" in the "Poset" menu)?

Here's an example:

L:=GraphicSubgroupLattice(G1xG2);

InsertVertex(L, HxK);
# insert here some command to change vertex label to "HxK"

InsertVertex(L, HxG2);
# insert here some command to change vertex label to "HxG2"

InsertVertex(L, G1xK);
# insert here some command to change vertex label to "G1xK"

intsubs:=IntermediateSubgroups(G1xG2, HxK);
for j in [1..Size(intsubs.subgroups)] do
    InsertVertex(L,intsubs.subgroups[j]);
od;

After I execute the loop, it's hard to tell what's what unless I have
already changed some labels with names like "HxK", "HxG2", etc. before
the loop.  Using the menu to do this each time is a bit tedious.

(Also, it would be nice if I could use some stored list of short names
-- maybe acquired from StructureDescription -- to insert labels inside
the loop as well, but maybe that's asking too much... and perhaps such
a labelling would be even harder to interpret than the default number
labels; e.g. when the names are not unique.)

Thanks in advance for any tips!

-William