def test_sympyissue_11020():
Lorentz = TensorIndexType('Lorentz', metric=False, dummy_fmt='i', dim=2)
Lorentz.data = [-1, 1]
a, b, c, d = tensor_indices('a, b, c, d', Lorentz)
i0, _ = tensor_indices('i_0:2', Lorentz)
Vec = TensorType([Lorentz], tensorsymmetry([1]))
S2 = TensorType([Lorentz] * 2, tensorsymmetry([1] * 2))
# metric tensor
g = S2('g')
g.data = Lorentz.data
u = Vec('u')
u.data = [1, 0]
add_1 = g(b, c) * g(d, i0) * u(-i0) - g(b, c) * u(d)
assert (add_1.data == numpy.zeros(shape=(2, 2, 2))).all()
# Now let us replace index `d` with `a`:
add_2 = g(b, c) * g(a, i0) * u(-i0) - g(b, c) * u(a)
assert (add_2.data == numpy.zeros(shape=(2, 2, 2))).all()
# some more tests
# perp is tensor orthogonal to u^\mu
perp = u(a) * u(b) + g(a, b)
mul_1 = u(-a) * perp(a, b)
assert (mul_1.data == numpy.array([0, 0])).all()
mul_2 = u(-c) * perp(c, a) * perp(d, b)
assert (mul_2.data == numpy.zeros(shape=(2, 2, 2))).all()
def test_tensorsymmetry():
sym = tensorsymmetry([1]*2)
sym1 = TensorSymmetry(get_symmetric_group_sgs(2))
assert sym == sym1
sym = tensorsymmetry([2])
sym1 = TensorSymmetry(get_symmetric_group_sgs(2, 1))
assert sym == sym1
sym2 = tensorsymmetry()
assert sym2.base == Tuple() and sym2.generators == Tuple(Permutation(1))
pytest.raises(NotImplementedError, lambda: tensorsymmetry([2, 1]))
def test_TensMul_data():
Lorentz = TensorIndexType('Lorentz', metric=False, dummy_fmt='L', dim=4)
Lorentz.data = [-1, 1, 1, 1]
mu, nu, alpha, beta = tensor_indices('\\mu, \\nu, \\alpha, \\beta',
Lorentz)
Vec = TensorType([Lorentz], tensorsymmetry([1]))
A2 = TensorType([Lorentz] * 2, tensorsymmetry([2]))
u = Vec('u')
u.data = [1, 0, 0, 0]
F = A2('F')
Ex, Ey, Ez, Bx, By, Bz = symbols('E_x E_y E_z B_x B_y B_z')
F.data = [[0, Ex, Ey, Ez],
[-Ex, 0, Bz, -By],
[-Ey, -Bz, 0, Bx],
[-Ez, By, -Bx, 0]]
E = F(mu, nu) * u(-nu)
assert ((E(mu) * E(nu)).data ==
numpy.array([[0, 0, 0, 0],
[0, Ex ** 2, Ex * Ey, Ex * Ez],
[0, Ex * Ey, Ey ** 2, Ey * Ez],
[0, Ex * Ez, Ey * Ez, Ez ** 2]])).all()
assert ((E(mu) * E(nu)).canon_bp().data == (E(mu) * E(nu)).data).all()
assert ((F(mu, alpha) * F(beta, nu) * u(-alpha) * u(-beta)).data ==
- (E(mu) * E(nu)).data).all()
assert ((F(alpha, mu) * F(beta, nu) * u(-alpha) * u(-beta)).data ==
(E(mu) * E(nu)).data).all()
S2 = TensorType([Lorentz] * 2, tensorsymmetry([1] * 2))
g = S2('g')
g.data = Lorentz.data
# tensor 'perp' is orthogonal to vector 'u'
perp = u(mu) * u(nu) + g(mu, nu)
mul_1 = u(-mu) * perp(mu, nu)
assert (mul_1.data == numpy.array([0, 0, 0, 0])).all()
mul_2 = u(-mu) * perp(mu, alpha) * perp(nu, beta)
assert (mul_2.data == numpy.zeros(shape=(4, 4, 4))).all()
Fperp = perp(mu, alpha) * perp(nu, beta) * F(-alpha, -beta)
assert (Fperp.data[0, :] == numpy.array([0, 0, 0, 0])).all()
assert (Fperp.data[:, 0] == numpy.array([0, 0, 0, 0])).all()
mul_3 = u(-mu) * Fperp(mu, nu)
assert (mul_3.data == numpy.array([0, 0, 0, 0])).all()
def test_TensorIndexType():
D = Symbol('D')
G = Metric('g', False)
Lorentz = TensorIndexType('Lorentz', metric=G, dim=D, dummy_fmt='L')
sym2 = tensorsymmetry([1] * 2)
sym2n = tensorsymmetry(*get_symmetric_group_sgs(2))
assert sym2 == sym2n
g = Lorentz.metric
assert str(g) == 'g(Lorentz,Lorentz)'
assert Lorentz.eps_dim == Lorentz.dim
TSpace = TensorIndexType('TSpace')
i0 = tensor_indices('i0', TSpace)
g = TSpace.metric
A = tensorhead('A', [TSpace] * 2, [[1] * 2])
assert str(A(i0, -i0).canon_bp()) == 'A(TSpace_0, -TSpace_0)'
def test_TensorHead():
assert TensAdd() == 0
# simple example of algebraic expression
Lorentz = TensorIndexType('Lorentz', dummy_fmt='L')
# A, B symmetric
A = tensorhead('A', [Lorentz] * 2, [[1] * 2])
assert A.rank == 2
assert A.symmetry == tensorsymmetry([1] * 2)
def test_canonicalize_no_dummies():
Lorentz = TensorIndexType('Lorentz', dummy_fmt='L')
a, b, c, d = tensor_indices('a, b, c, d', Lorentz)
sym1 = tensorsymmetry([1])
sym2 = tensorsymmetry([1]*2)
# A commuting
# A^c A^b A^a
# T_c = A^a A^b A^c
S1 = TensorType([Lorentz], sym1)
A = S1('A')
t = A(c)*A(b)*A(a)
tc = t.canon_bp()
assert str(tc) == 'A(a)*A(b)*A(c)'
# A anticommuting
# A^c A^b A^a
# T_c = -A^a A^b A^c
A = S1('A', 1)
t = A(c)*A(b)*A(a)
tc = t.canon_bp()
assert str(tc) == '-A(a)*A(b)*A(c)'
# A commuting and symmetric
# A^{b,d}*A^{c,a}
# T_c = A^{a c}*A^{b d}
S2 = TensorType([Lorentz]*2, sym2)
A = S2('A')
t = A(b, d)*A(c, a)
tc = t.canon_bp()
assert str(tc) == 'A(a, c)*A(b, d)'
# A anticommuting and symmetric
# A^{b,d}*A^{c,a}
# T_c = -A^{a c}*A^{b d}
A = S2('A', 1)
t = A(b, d)*A(c, a)
tc = t.canon_bp()
assert str(tc) == '-A(a, c)*A(b, d)'
# A^{c,a}*A^{b,d}
# T_c = A^{a c}*A^{b d}
t = A(c, a)*A(b, d)
tc = t.canon_bp()
assert str(tc) == 'A(a, c)*A(b, d)'
def test_TensorType():
Lorentz = TensorIndexType('Lorentz', dummy_fmt='L')
sym = tensorsymmetry([1]*2)
A = tensorhead('A', [Lorentz]*2, [[1]*2])
assert A.typ == TensorType([Lorentz]*2, sym)
assert A.types == [Lorentz]
typ = TensorType([Lorentz]*2, sym)
assert str(typ) == "TensorType(['Lorentz', 'Lorentz'])"
pytest.raises(ValueError, lambda: typ(2))
def test_hash():
D = Symbol('D')
Lorentz = TensorIndexType('Lorentz', dim=D, dummy_fmt='L')
a, b, c, d, e = tensor_indices('a,b,c,d,e', Lorentz)
g = Lorentz.metric
p, q = tensorhead('p q', [Lorentz], [[1]])
p_type = p.args[1]
t1 = p(a)*q(b)
t2 = p(a)*p(b)
assert hash(t1) != hash(t2)
t3 = p(a)*p(b) + g(a, b)
t4 = p(a)*p(b) - g(a, b)
assert hash(t3) != hash(t4)
assert a.func(*a.args) == a
assert Lorentz.func(*Lorentz.args) == Lorentz
assert g.func(*g.args) == g
assert p.func(*p.args) == p
assert p_type.func(*p_type.args) == p_type
assert p(a).func(*(p(a)).args) == p(a)
assert t1.func(*t1.args) == t1
assert t2.func(*t2.args) == t2
assert t3.func(*t3.args) == t3
assert t4.func(*t4.args) == t4
assert hash(a.func(*a.args)) == hash(a)
assert hash(Lorentz.func(*Lorentz.args)) == hash(Lorentz)
assert hash(g.func(*g.args)) == hash(g)
assert hash(p.func(*p.args)) == hash(p)
assert hash(p_type.func(*p_type.args)) == hash(p_type)
assert hash(p(a).func(*(p(a)).args)) == hash(p(a))
assert hash(t1.func(*t1.args)) == hash(t1)
assert hash(t2.func(*t2.args)) == hash(t2)
assert hash(t3.func(*t3.args)) == hash(t3)
assert hash(t4.func(*t4.args)) == hash(t4)
def check_all(obj):
return all(isinstance(_, Basic) for _ in obj.args)
assert check_all(a)
assert check_all(Lorentz)
assert check_all(g)
assert check_all(p)
assert check_all(p_type)
assert check_all(p(a))
assert check_all(t1)
assert check_all(t2)
assert check_all(t3)
assert check_all(t4)
tsymmetry = tensorsymmetry([2], [1], [1, 1, 1])
assert tsymmetry.func(*tsymmetry.args) == tsymmetry
assert hash(tsymmetry.func(*tsymmetry.args)) == hash(tsymmetry)
assert check_all(tsymmetry)
def test_sympyissue_10972_TensMul_data():
Lorentz = TensorIndexType('Lorentz', metric=False, dummy_fmt='i', dim=2)
Lorentz.data = [-1, 1]
mu, nu, alpha, beta = tensor_indices('\\mu, \\nu, \\alpha, \\beta',
Lorentz)
Vec = TensorType([Lorentz], tensorsymmetry([1]))
A2 = TensorType([Lorentz] * 2, tensorsymmetry([2]))
u = Vec('u')
u.data = [1, 0]
F = A2('F')
F.data = [[0, 1], [-1, 0]]
mul_1 = F(mu, alpha) * u(-alpha) * F(nu, beta) * u(-beta)
assert (mul_1.data == numpy.array([[0, 0], [0, 1]])).all()
mul_2 = F(mu, alpha) * F(nu, beta) * u(-alpha) * u(-beta)
assert (mul_2.data == mul_1.data).all()
assert ((mul_1 + mul_1).data == 2 * mul_1.data).all()
def test_mul():
Lorentz = TensorIndexType('Lorentz', dummy_fmt='L')
a, b, c, d = tensor_indices('a,b,c,d', Lorentz)
t = TensMul.from_data(Integer(1), [], [], [])
assert str(t) == '1'
A, B = tensorhead('A B', [Lorentz]*2, [[1]*2])
t = (1 + x)*A(a, b)
assert str(t) == '(x + 1)*A(a, b)'
assert t.types == [Lorentz]
assert t.rank == 2
assert t.dum == []
assert t.coeff == 1 + x
assert sorted(t.free) == [(a, 0, 0), (b, 1, 0)]
assert t.components == [A]
ts = A(a, b)
assert str(ts) == 'A(a, b)'
assert ts.types == [Lorentz]
assert ts.rank == 2
assert ts.dum == []
assert ts.coeff == 1
assert sorted(ts.free) == [(a, 0, 0), (b, 1, 0)]
assert ts.components == [A]
t = A(-b, a)*B(-a, c)*A(-c, d)
t1 = tensor_mul(*t.split())
assert t == t(-b, d)
assert t == t1
assert tensor_mul(*[]) == TensMul.from_data(Integer(1), [], [], [])
t = TensMul.from_data(1, [], [], [])
zsym = tensorsymmetry()
typ = TensorType([], zsym)
C = typ('C')
assert str(C()) == 'C'
assert str(t) == '1'
assert t.split()[0] == t
pytest.raises(ValueError, lambda: TIDS.free_dum_from_indices(a, a))
pytest.raises(ValueError, lambda: TIDS.free_dum_from_indices(-a, -a))
pytest.raises(ValueError, lambda: A(a, b)*A(a, c))
t = A(a, b)*A(-a, c)
pytest.raises(ValueError, lambda: t(a, b, c))
def test_canonicalize_no_slot_sym():
# A_d0 * B^d0; T_c = A^d0*B_d0
Lorentz = TensorIndexType('Lorentz', dummy_fmt='L')
a, b, d0, d1 = tensor_indices('a,b,d0,d1', Lorentz)
sym1 = tensorsymmetry([1])
S1 = TensorType([Lorentz], sym1)
A, B = S1('A,B')
t = A(-d0)*B(d0)
tc = t.canon_bp()
assert str(tc) == 'A(L_0)*B(-L_0)'
# A^a * B^b; T_c = T
t = A(a)*B(b)
tc = t.canon_bp()
assert tc == t
# B^b * A^a
t1 = B(b)*A(a)
tc = t1.canon_bp()
assert str(tc) == 'A(a)*B(b)'
# A symmetric
# A^{b}_{d0}*A^{d0, a}; T_c = A^{a d0}*A{b}_{d0}
sym2 = tensorsymmetry([1]*2)
S2 = TensorType([Lorentz]*2, sym2)
A = S2('A')
t = A(b, -d0)*A(d0, a)
tc = t.canon_bp()
assert str(tc) == 'A(a, L_0)*A(b, -L_0)'
# A^{d1}_{d0}*B^d0*C_d1
# T_c = A^{d0 d1}*B_d0*C_d1
B, C = S1('B,C')
t = A(d1, -d0)*B(d0)*C(-d1)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-L_0)*C(-L_1)'
# A without symmetry
# A^{d1}_{d0}*B^d0*C_d1 ord=[d0,-d0,d1,-d1]; g = [2,1,0,3,4,5]
# T_c = A^{d0 d1}*B_d1*C_d0; can = [0,2,3,1,4,5]
nsym2 = tensorsymmetry([1], [1])
NS2 = TensorType([Lorentz]*2, nsym2)
A = NS2('A')
B, C = S1('B, C')
t = A(d1, -d0)*B(d0)*C(-d1)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-L_1)*C(-L_0)'
# A, B without symmetry
# A^{d1}_{d0}*B_{d1}^{d0}
# T_c = A^{d0 d1}*B_{d0 d1}
B = NS2('B')
t = A(d1, -d0)*B(-d1, d0)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-L_0, -L_1)'
# A_{d0}^{d1}*B_{d1}^{d0}
# T_c = A^{d0 d1}*B_{d1 d0}
t = A(-d0, d1)*B(-d1, d0)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-L_1, -L_0)'
# A, B, C without symmetry
# A^{d1 d0}*B_{a d0}*C_{d1 b}
# T_c=A^{d0 d1}*B_{a d1}*C_{d0 b}
C = NS2('C')
t = A(d1, d0)*B(-a, -d0)*C(-d1, -b)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-a, -L_1)*C(-L_0, -b)'
# A symmetric, B and C without symmetry
# A^{d1 d0}*B_{a d0}*C_{d1 b}
# T_c = A^{d0 d1}*B_{a d0}*C_{d1 b}
A = S2('A')
t = A(d1, d0)*B(-a, -d0)*C(-d1, -b)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-a, -L_0)*C(-L_1, -b)'
# A and C symmetric, B without symmetry
# A^{d1 d0}*B_{a d0}*C_{d1 b} ord=[a,b,d0,-d0,d1,-d1]
# T_c = A^{d0 d1}*B_{a d0}*C_{b d1}
C = S2('C')
t = A(d1, d0)*B(-a, -d0)*C(-d1, -b)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1)*B(-a, -L_0)*C(-b, -L_1)'
pytest.raises(TypeError, lambda: TensorType(1, 2, 3))
pytest.raises(ValueError, lambda: TensorHead((1, 2), NS2))
def test_canonicalize1():
Lorentz = TensorIndexType('Lorentz', dummy_fmt='L')
a, a0, a1, a2, a3, b, d0, d1, d2, d3 = \
tensor_indices('a,a0,a1,a2,a3,b,d0,d1,d2,d3', Lorentz)
sym1 = tensorsymmetry([1])
base3, gens3 = get_symmetric_group_sgs(3)
sym2 = tensorsymmetry([1]*2)
sym2a = tensorsymmetry([2])
sym3 = tensorsymmetry([1]*3)
sym3a = tensorsymmetry([3])
# A_d0*A^d0; ord = [d0,-d0]
# T_c = A^d0*A_d0
S1 = TensorType([Lorentz], sym1)
A = S1('A')
t = A(-d0)*A(d0)
tc = t.canon_bp()
assert str(tc) == 'A(L_0)*A(-L_0)'
# A commuting
# A_d0*A_d1*A_d2*A^d2*A^d1*A^d0
# T_c = A^d0*A_d0*A^d1*A_d1*A^d2*A_d2
t = A(-d0)*A(-d1)*A(-d2)*A(d2)*A(d1)*A(d0)
tc = t.canon_bp()
assert str(tc) == 'A(L_0)*A(-L_0)*A(L_1)*A(-L_1)*A(L_2)*A(-L_2)'
# A anticommuting
# A_d0*A_d1*A_d2*A^d2*A^d1*A^d0
# T_c 0
A = S1('A', 1)
t = A(-d0)*A(-d1)*A(-d2)*A(d2)*A(d1)*A(d0)
tc = t.canon_bp()
assert tc == 0
# A commuting symmetric
# A^{d0 b}*A^a_d1*A^d1_d0
# T_c = A^{a d0}*A^{b d1}*A_{d0 d1}
S2 = TensorType([Lorentz]*2, sym2)
A = S2('A')
t = A(d0, b)*A(a, -d1)*A(d1, -d0)
tc = t.canon_bp()
assert str(tc) == 'A(a, L_0)*A(b, L_1)*A(-L_0, -L_1)'
# A, B commuting symmetric
# A^{d0 b}*A^d1_d0*B^a_d1
# T_c = A^{b d0}*A_d0^d1*B^a_d1
B = S2('B')
t = A(d0, b)*A(d1, -d0)*B(a, -d1)
tc = t.canon_bp()
assert str(tc) == 'A(b, L_0)*A(-L_0, L_1)*B(a, -L_1)'
# A commuting symmetric
# A^{d1 d0 b}*A^{a}_{d1 d0}; ord=[a,b, d0,-d0,d1,-d1]
# T_c = A^{a d0 d1}*A^{b}_{d0 d1}
S3 = TensorType([Lorentz]*3, sym3)
A = S3('A')
t = A(d1, d0, b)*A(a, -d1, -d0)
tc = t.canon_bp()
assert str(tc) == 'A(a, L_0, L_1)*A(b, -L_0, -L_1)'
# A^{d3 d0 d2}*A^a0_{d1 d2}*A^d1_d3^a1*A^{a2 a3}_d0
# T_c = A^{a0 d0 d1}*A^a1_d0^d2*A^{a2 a3 d3}*A_{d1 d2 d3}
t = A(d3, d0, d2)*A(a0, -d1, -d2)*A(d1, -d3, a1)*A(a2, a3, -d0)
tc = t.canon_bp()
assert str(tc) == 'A(a0, L_0, L_1)*A(a1, -L_0, L_2)*A(a2, a3, L_3)*A(-L_1, -L_2, -L_3)'
# A commuting symmetric, B antisymmetric
# A^{d0 d1 d2} * A_{d2 d3 d1} * B_d0^d3
# in this esxample and in the next three,
# renaming dummy indices and using symmetry of A,
# T = A^{d0 d1 d2} * A_{d0 d1 d3} * B_d2^d3
# can = 0
S2a = TensorType([Lorentz]*2, sym2a)
A = S3('A')
B = S2a('B')
t = A(d0, d1, d2)*A(-d2, -d3, -d1)*B(-d0, d3)
tc = t.canon_bp()
assert tc == 0
# A anticommuting symmetric, B anticommuting
# A^{d0 d1 d2} * A_{d2 d3 d1} * B_d0^d3
# T_c = A^{d0 d1 d2} * A_{d0 d1}^d3 * B_{d2 d3}
A = S3('A', 1)
B = S2a('B')
t = A(d0, d1, d2)*A(-d2, -d3, -d1)*B(-d0, d3)
tc = t.canon_bp()
assert str(tc) == 'A(L_0, L_1, L_2)*A(-L_0, -L_1, L_3)*B(-L_2, -L_3)'
# A anticommuting symmetric, B antisymmetric commuting, antisymmetric metric
# A^{d0 d1 d2} * A_{d2 d3 d1} * B_d0^d3
# T_c = -A^{d0 d1 d2} * A_{d0 d1}^d3 * B_{d2 d3}
Spinor = TensorIndexType('Spinor', metric=1, dummy_fmt='S')
a, a0, a1, a2, a3, b, d0, d1, d2, d3 = \
tensor_indices('a,a0,a1,a2,a3,b,d0,d1,d2,d3', Spinor)
S3 = TensorType([Spinor]*3, sym3)
S2a = TensorType([Spinor]*2, sym2a)
A = S3('A', 1)
B = S2a('B')
t = A(d0, d1, d2)*A(-d2, -d3, -d1)*B(-d0, d3)
tc = t.canon_bp()
assert str(tc) == '-A(S_0, S_1, S_2)*A(-S_0, -S_1, S_3)*B(-S_2, -S_3)'
# A anticommuting symmetric, B antisymmetric anticommuting,
# no metric symmetry
# A^{d0 d1 d2} * A_{d2 d3 d1} * B_d0^d3
# T_c = A^{d0 d1 d2} * A_{d0 d1 d3} * B_d2^d3
Mat = TensorIndexType('Mat', metric=None, dummy_fmt='M')
a, a0, a1, a2, a3, b, d0, d1, d2, d3 = \
tensor_indices('a,a0,a1,a2,a3,b,d0,d1,d2,d3', Mat)
S3 = TensorType([Mat]*3, sym3)
S2a = TensorType([Mat]*2, sym2a)
A = S3('A', 1)
B = S2a('B')
t = A(d0, d1, d2)*A(-d2, -d3, -d1)*B(-d0, d3)
tc = t.canon_bp()
assert str(tc) == 'A(M_0, M_1, M_2)*A(-M_0, -M_1, -M_3)*B(-M_2, M_3)'
# Gamma anticommuting
# Gamma_{mu nu} * gamma^rho * Gamma^{nu mu alpha}
# T_c = -Gamma^{mu nu} * gamma^rho * Gamma_{alpha mu nu}
S1 = TensorType([Lorentz], sym1)
S2a = TensorType([Lorentz]*2, sym2a)
S3a = TensorType([Lorentz]*3, sym3a)
alpha, beta, gamma, mu, nu, rho = \
tensor_indices('alpha,beta,gamma,mu,nu,rho', Lorentz)
Gamma = S1('Gamma', 2)
Gamma2 = S2a('Gamma', 2)
Gamma3 = S3a('Gamma', 2)
t = Gamma2(-mu, -nu)*Gamma(rho)*Gamma3(nu, mu, alpha)
tc = t.canon_bp()
assert str(tc) == '-Gamma(L_0, L_1)*Gamma(rho)*Gamma(alpha, -L_0, -L_1)'
# Gamma_{mu nu} * Gamma^{gamma beta} * gamma_rho * Gamma^{nu mu alpha}
# T_c = Gamma^{mu nu} * Gamma^{beta gamma} * gamma_rho * Gamma^alpha_{mu nu}
t = Gamma2(mu, nu)*Gamma2(beta, gamma)*Gamma(-rho)*Gamma3(alpha, -mu, -nu)
tc = t.canon_bp()
assert str(tc) == 'Gamma(L_0, L_1)*Gamma(beta, gamma)*Gamma(-rho)*Gamma(alpha, -L_0, -L_1)'
# f^a_{b,c} antisymmetric in b,c; A_mu^a no symmetry
# f^c_{d a} * f_{c e b} * A_mu^d * A_nu^a * A^{nu e} * A^{mu b}
# g = [8,11,5, 9,13,7, 1,10, 3,4, 2,12, 0,6, 14,15]
# T_c = -f^{a b c} * f_a^{d e} * A^mu_b * A_{mu d} * A^nu_c * A_{nu e}
Flavor = TensorIndexType('Flavor', dummy_fmt='F')
a, b, c, d, e, ff = tensor_indices('a,b,c,d,e,f', Flavor)
mu, nu = tensor_indices('mu,nu', Lorentz)
sym_f = tensorsymmetry([1], [2])
S_f = TensorType([Flavor]*3, sym_f)
sym_A = tensorsymmetry([1], [1])
S_A = TensorType([Lorentz, Flavor], sym_A)
f = S_f('f')
A = S_A('A')
t = f(c, -d, -a)*f(-c, -e, -b)*A(-mu, d)*A(-nu, a)*A(nu, e)*A(mu, b)
tc = t.canon_bp()
assert str(tc) == '-f(F_0, F_1, F_2)*f(-F_0, F_3, F_4)*A(L_0, -F_1)*A(-L_0, -F_3)*A(L_1, -F_2)*A(-L_1, -F_4)'
