Exemple #1
0
def test_PermutationGroup():
    assert PermutationGroup() == PermutationGroup(Permutation())

    a = Permutation(1, 2)
    b = Permutation(2, 3, 1)
    G = PermutationGroup(a, b, degree=5)
    assert G.contains(G[0])

    A = AlternatingGroup(4)
    A.schreier_sims()
    assert A.base == [0, 1]
    assert A.basic_stabilizers == [
        PermutationGroup(Permutation(0, 1, 2), Permutation(1, 2, 3)),
        PermutationGroup(Permutation(1, 2, 3))
    ]

    D = DihedralGroup(12)
    assert D.is_primitive(randomized=False) is False

    D = DihedralGroup(10)
    assert D.is_primitive() is False

    p = Permutation(0, 1, 2, 3, 4, 5)
    G1 = PermutationGroup([Permutation(0, 1, 2), Permutation(0, 1)])
    G2 = PermutationGroup([Permutation(0, 2), Permutation(0, 1, 2)])
    G3 = PermutationGroup([p, p**2])
    assert G1.order() == G2.order() == G3.order() == 6
    assert G1.is_subgroup(G2) is True
    assert G1.is_subgroup(G3) is False

    a, b = [Permutation([1, 0, 3, 2]), Permutation([1, 3, 0, 2])]
    G = PermutationGroup([a, b])
    assert G.make_perm([0, 1, 0]) == Permutation(0, 2, 3, 1)

    S = SymmetricGroup(5)
    base, strong_gens = S.schreier_sims_random()
    assert _verify_bsgs(S, base, strong_gens)

    D = DihedralGroup(4)
    assert D.strong_gens == [
        Permutation(0, 1, 2, 3),
        Permutation(0, 3)(1, 2),
        Permutation(1, 3)
    ]

    a = Permutation([1, 2, 0])
    b = Permutation([1, 0, 2])
    G = PermutationGroup([a, b])
    assert G.transitivity_degree == 3

    a = Permutation([1, 2, 0, 4, 5, 6, 3])
    G = PermutationGroup([a])
    assert G.orbit(0) == {0, 1, 2}
    assert G.orbit([0, 4], 'union') == {0, 1, 2, 3, 4, 5, 6}
    assert G.orbit([0, 4], 'sets') == {(0, 3), (0, 4), (0, 5), (0, 6), (1, 3),
                                       (1, 4), (1, 5), (1, 6), (2, 3), (2, 4),
                                       (2, 5), (2, 6)}
    assert G.orbit([0, 4], 'tuples') == {(0, 3), (0, 4), (0, 5), (0, 6),
                                         (1, 3), (1, 4), (1, 5), (1, 6),
                                         (2, 3), (2, 4), (2, 5), (2, 6)}
def test_orbits():
    a = Permutation([2, 0, 1])
    b = Permutation([2, 1, 0])
    g = PermutationGroup([a, b])
    assert g.orbit(0) == {0, 1, 2}
    assert g.orbits() == [{0, 1, 2}]
    assert g.is_transitive() and g.is_transitive(strict=False)
    assert g.orbit_transversal(0) == \
        [Permutation(
            [0, 1, 2]), Permutation([2, 0, 1]), Permutation([1, 2, 0])]
    assert g.orbit_transversal(0, True) == \
        [(0, Permutation([0, 1, 2])), (2, Permutation([2, 0, 1])),
         (1, Permutation([1, 2, 0]))]

    a = Permutation(list(range(1, 100)) + [0])
    G = PermutationGroup([a])
    assert [min(o) for o in G.orbits()] == [0]
    G = PermutationGroup(rubik_cube_generators())
    assert [min(o) for o in G.orbits()] == [0, 1]
    assert not G.is_transitive() and not G.is_transitive(strict=False)
    G = PermutationGroup([Permutation(0, 1, 3), Permutation(3)(0, 1)])
    assert not G.is_transitive() and G.is_transitive(strict=False)
    assert PermutationGroup(
        Permutation(3)).is_transitive(strict=False) is False