def test_get_state():
q = Qubits(2)
q.set_state('11')
assert np.allclose(
q.get_state(),
np.array([0, 0, 0, 1])
)
q.set_state('01')
assert np.allclose(
q.get_state(flatten=False),
np.array([[0, 1], [0, 0]])
)
def test_expect():
q = Qubits(2)
res = q.expect(np.kron(I, I))
assert res == 1
q = Qubits(2)
res = q.expect(np.kron(I, X))
assert res == 0
q = Qubits(2)
res = q.expect({'YI': 2.5, 'II': 2, 'IX': 1.5, 'IZ': 1})
assert res == 3
q = Qubits(2)
q.set_state('01')
res = q.expect({'IZ': 2})
assert res == -2
q = Qubits(2)
q.set_state('10')
res = q.expect({'IZ': 2})
assert res == 2
q = Qubits(2)
q.set_state('01')
res = q.expect({'ZI': 2})
assert res == 2
q = Qubits(2)
q.set_state('11')
res = q.expect({'ZZ': 2})
assert res == 2
def test_set_state():
q = Qubits(2)
q.set_state('10')
assert q.data[0, 0] == 0
assert q.data[0, 1] == 0
assert q.data[1, 0] == 1
assert q.data[1, 1] == 0
assert np.allclose(
q.data.flatten(),
np.array([0, 0, 1, 0])
)
q.set_state([0, 1, 0, 0])
assert q.data[0, 0] == 0
assert q.data[0, 1] == 1
assert q.data[1, 0] == 0
assert q.data[1, 1] == 0
assert np.allclose(
q.data.flatten(),
np.array([0, 1, 0, 0])
)
q.set_state([[0, 0], [0, 1]])
assert q.data[0, 0] == 0
assert q.data[0, 1] == 0
assert q.data[1, 0] == 0
assert q.data[1, 1] == 1
assert np.allclose(
q.data,
np.array([[0, 0], [0, 1]])
)