This function produces has the same output map(F,G,matrix f). This function is most useful when the either source/target of $f$ is isomorphic to $F/G$ as a module with basis, but not as a labeled module.
i1 : S=QQ[x,y,z];
i2 : A=labeledModule(S^2)
2
o2 = S
o2 : free S-module with labeled basis
i3 : F=(A**A)**A
8
o3 = S
o3 : free S-module with labeled basis
i4 : G=A**(A**A)
8
o4 = S
o4 : free S-module with labeled basis