def test_generate(): a = Permutation([1, 0]) g = list(PermutationGroup([a]).generate()) assert g == [Permutation([0, 1]), Permutation([1, 0])] assert len(list(PermutationGroup(Permutation((0, 1))).generate())) == 1 g = PermutationGroup([a]).generate(method='dimino') assert list(g) == [Permutation([0, 1]), Permutation([1, 0])] a = Permutation([2, 0, 1]) b = Permutation([2, 1, 0]) G = PermutationGroup([a, b]) g = G.generate() v1 = [p.array_form for p in list(g)] v1.sort() assert v1 == [[0, 1, 2], [0, 2, 1], [1, 0, 2], [1, 2, 0], [2, 0, 1], [2, 1, 0]] v2 = list(G.generate(method='dimino', af=True)) assert v1 == sorted(v2) a = Permutation([2, 0, 1, 3, 4, 5]) b = Permutation([2, 1, 3, 4, 5, 0]) g = PermutationGroup([a, b]).generate(af=True) assert len(list(g)) == 360
def test_coset_rank(): gens_cube = [[1, 3, 5, 7, 0, 2, 4, 6], [1, 3, 0, 2, 5, 7, 4, 6]] gens = [Permutation(p) for p in gens_cube] G = PermutationGroup(gens) i = 0 for h in G.generate(af=True): rk = G.coset_rank(h) assert rk == i h1 = G.coset_unrank(rk, af=True) assert h == h1 i += 1 assert G.coset_unrank(48) is None assert G.coset_unrank(G.coset_rank(gens[0])) == gens[0]
def canonicalize_naive(g, dummies, sym, *v): """ Canonicalize tensor formed by tensors of the different types g permutation representing the tensor dummies list of dummy indices msym symmetry of the metric v is a list of (base_i, gens_i, n_i, sym_i) for tensors of type `i` base_i, gens_i BSGS for tensors of this type n_i number ot tensors of type `i` sym_i symmetry under exchange of two component tensors of type `i` None no symmetry 0 commuting 1 anticommuting Return 0 if the tensor is zero, else return the array form of the permutation representing the canonical form of the tensor. Examples ======== >>> from diofant.combinatorics.testutil import canonicalize_naive >>> from diofant.combinatorics.tensor_can import get_symmetric_group_sgs >>> from diofant.combinatorics import Permutation, PermutationGroup >>> g = Permutation([1, 3, 2, 0, 4, 5]) >>> base2, gens2 = get_symmetric_group_sgs(2) >>> canonicalize_naive(g, [2, 3], 0, (base2, gens2, 2, 0)) [0, 2, 1, 3, 4, 5] """ from diofant.combinatorics.perm_groups import PermutationGroup from diofant.combinatorics.tensor_can import gens_products, dummy_sgs from diofant.combinatorics.permutations import Permutation, _af_rmul v1 = [] for i in range(len(v)): base_i, gens_i, n_i, sym_i = v[i] v1.append((base_i, gens_i, [[]]*n_i, sym_i)) size, sbase, sgens = gens_products(*v1) dgens = dummy_sgs(dummies, sym, size-2) if isinstance(sym, int): num_types = 1 dummies = [dummies] sym = [sym] else: num_types = len(sym) dgens = [] for i in range(num_types): dgens.extend(dummy_sgs(dummies[i], sym[i], size - 2)) S = PermutationGroup(sgens) D = PermutationGroup([Permutation(x) for x in dgens]) dlist = list(D.generate(af=True)) g = g.array_form st = set() for s in S.generate(af=True): h = _af_rmul(g, s) for d in dlist: q = tuple(_af_rmul(d, h)) st.add(q) a = list(st) a.sort() prev = (0,)*size for h in a: if h[:-2] == prev[:-2]: if h[-1] != prev[-1]: return 0 prev = h return list(a[0])