[GAP Forum] finding automorphisms of finitely presented groups

[Robert Heffernan]

I am dealing with groups constructed in this manner:
F:=FreeGroup("x","y","z");G:=F/rels;
where rels is some list of relations in terms of x,y and z.
If the group is large GAP seems to have trouble constructing the groupof automorphisms of G.
I understand that doing this:G:=Image(IsomorphismPermGroup(G));would give me a representation of the group that GAP can deal witheasily (and easily compute Aut G, etc.), but I want to look at theautomorphisms in terms of the generators x,y and z above.
Specifially, I am trying to find all the automorphisms G->G of a given order.
Is there an efficient way to do this?
thank you,
Bob