# Revision history [back]

### combinatorial equivalence for Polyhedra / isomorphism for lattices

Is there an easy way to check whether two polyhedra are combinatorial equivalent, i.e. have have isomorphic face lattices.

this does not work:

Poly1=Polyhedron(vertices=[[0,1],[1,0],[1,1]], base_ring=QQ)
Poly2=Polyhedron(vertices=[[2,0],[2,2],[0,2]], base_ring=QQ)
Poly1.face_lattice()==Poly2.face_lattice()


In this case this would work:

str(Poly1.faces(1))==str(Poly2.faces(1))


but what would be a good way to check this in general?

 2 retagged FrédéricC 5151 ●3 ●43 ●112

### combinatorial equivalence for Polyhedra / isomorphism for lattices

Is there an easy way to check whether two polyhedra are combinatorial equivalent, i.e. have have isomorphic face lattices.

this does not work:

Poly1=Polyhedron(vertices=[[0,1],[1,0],[1,1]], base_ring=QQ)
Poly2=Polyhedron(vertices=[[2,0],[2,2],[0,2]], base_ring=QQ)
Poly1.face_lattice()==Poly2.face_lattice()


In this case this would work:

str(Poly1.faces(1))==str(Poly2.faces(1))


but what would be a good way to check this in general?

 3 retagged FrédéricC 5151 ●3 ●43 ●112

### combinatorial equivalence for Polyhedra / isomorphism for lattices

Is there an easy way to check whether two polyhedra are combinatorial equivalent, i.e. have have isomorphic face lattices.

this does not work:

Poly1=Polyhedron(vertices=[[0,1],[1,0],[1,1]], base_ring=QQ)
Poly2=Polyhedron(vertices=[[2,0],[2,2],[0,2]], base_ring=QQ)
Poly1.face_lattice()==Poly2.face_lattice()


In this case this would work:

str(Poly1.faces(1))==str(Poly2.faces(1))


but what would be a good way to check this in general?