def test_quantum_state():
state_vector_1 = cirq.one_hot(shape=(4,), dtype=np.complex128)
state_tensor_1 = np.reshape(state_vector_1, (2, 2))
density_matrix_1 = np.outer(state_vector_1, np.conj(state_vector_1))
state = cirq.QuantumState(state_vector_1, qid_shape=(2, 2))
assert state.data is state_vector_1
assert state.qid_shape == (2, 2)
assert state.dtype == np.complex128
np.testing.assert_array_equal(state.state_vector(), state_vector_1)
np.testing.assert_array_equal(state.state_tensor(), state_tensor_1)
np.testing.assert_array_equal(state.density_matrix(), density_matrix_1)
np.testing.assert_array_equal(state.state_vector_or_density_matrix(), state_vector_1)
state = cirq.QuantumState(state_tensor_1, qid_shape=(2, 2))
assert state.data is state_tensor_1
assert state.qid_shape == (2, 2)
assert state.dtype == np.complex128
np.testing.assert_array_equal(state.state_vector(), state_vector_1)
np.testing.assert_array_equal(state.state_tensor(), state_tensor_1)
np.testing.assert_array_equal(state.density_matrix(), density_matrix_1)
np.testing.assert_array_equal(state.state_vector_or_density_matrix(), state_vector_1)
state = cirq.QuantumState(density_matrix_1, qid_shape=(2, 2))
assert state.data is density_matrix_1
assert state.qid_shape == (2, 2)
assert state.dtype == np.complex128
assert state.state_vector() is None
assert state.state_tensor() is None
np.testing.assert_array_equal(state.density_matrix(), density_matrix_1)
np.testing.assert_array_equal(state.state_vector_or_density_matrix(), density_matrix_1)
def test_quantum_state_quantum_state():
state_vector_1 = cirq.one_hot(shape=(4,), dtype=np.complex128)
quantum_state = cirq.QuantumState(state_vector_1, qid_shape=(2, 2))
state = cirq.quantum_state(quantum_state)
assert state is quantum_state
assert state.data is quantum_state.data
assert state.dtype == np.complex128
state = cirq.quantum_state(quantum_state, copy=True)
assert state is not quantum_state
assert state.data is not quantum_state.data
assert state.dtype == np.complex128
state = cirq.quantum_state(quantum_state, dtype=np.complex64)
assert state is not quantum_state
assert state.data is not quantum_state.data
assert state.dtype == np.complex64
with pytest.raises(ValueError, match='qid shape'):
state = cirq.quantum_state(quantum_state, qid_shape=(4,))