intrinsic WG2GroupRep(W::GrpFPCox,wg::GrphUnd) -> SeqEnum { The matrix representation of a W-graph } rank := Rank(W); V := Vertices(wg); E := Edges(wg); L:=Parent(Label(E[1])); graphrank := #V; JR:=[]; for s in [1..rank] do Q := [ s in Label(u) select else : u in V | true where i is Index(u) ]; for e in E do u := InitialVertex(e); v := TerminalVertex(e); if s in Label(u) and s notin Label(v) then Append(~Q, ); elif s in Label(v) and s notin Label(u) then Append(~Q, ); end if; end for; JR[s] := SparseMatrix( L,graphrank,graphrank,Q ); vprint WGraph, 2 : "Matrix representing generator",s,"constructed"; end for; return JR; end intrinsic; intrinsic WG2GroupRep(W::GrpFPCox,wg::GrphDir) -> SeqEnum { The matrix representation of a W-graph } rank := Rank(W); V := Vertices(wg); E := Edges(wg); L:=Parent(Label(E[1])); graphrank := #V; JR:=[]; for s in [1..rank] do Q := [ s in Label(u) select else : u in V | true where i is Index(u) ]; for e in E do u := InitialVertex(e); v := TerminalVertex(e); if s in Label(u) and s notin Label(v) then Append(~Q, ); end if; end for; JR[s] := SparseMatrix( L,graphrank,graphrank,Q ); vprint WGraph, 2 : "Matrix representing generator",s,"constructed"; end for; return JR; end intrinsic;