def test_bell_state(self):
p = qu.bell_state('psi-')
assert_allclose(qu.schmidt_gap(p, [2, 2], 0), 0.0)
p = qu.up() & qu.down()
assert_allclose(qu.schmidt_gap(p, [2, 2], 0), 1.0)
p = qu.rand_ket(2**3)
assert 0 < qu.schmidt_gap(p, [2] * 3, sysa=[0, 1]) < 1.0
def test_bell_state(self):
p = bell_state('psi-')
assert_allclose(schmidt_gap(p, [2, 2], 0), 0.0)
p = up() & down()
assert_allclose(schmidt_gap(p, [2, 2], 0), 1.0)
p = rand_ket(2**3)
assert 0 < schmidt_gap(p, [2] * 3, sysa=[0, 1]) < 1.0
def test_schmidt_values_entropy_gap_simple(self):
n = 12
p = MPS_rand_state(n, 16)
p.right_canonize()
svns = []
sgs = []
for i in range(1, n):
sgs.append(p.schmidt_gap(i, current_orthog_centre=i - 1))
svns.append(p.entropy(i, current_orthog_centre=i))
pd = p.to_dense()
ex_svns = [entropy_subsys(pd, [2] * n, range(i)) for i in range(1, n)]
ex_sgs = [schmidt_gap(pd, [2] * n, range(i)) for i in range(1, n)]
assert_allclose(ex_svns, svns)
assert_allclose(ex_sgs, sgs)