collateVertices(G)
Let G=mixedGraph(U,D,B) and denote the vertices of U by V1, the vertices of D by V2 and the vertices of B by V3. Then the method collateVertices(G) outputs a mixedGraph with same edges as before but with V1 \cup V2 \cup V3 as the vertices of U,D and B.





The object collateVertices is a method function.