def test_kraus_through_qvm_t2():
noise = NoiseModel(T1=INFINITY, ro_fidelity=1.0)
qvm = QVMConnection(type_trans='density', noise_model=noise)
rho = random_1q_density()
identity_program = Program().inst(Igate(0))
qvm._density = sps.csc_matrix(rho)
qvm.num_qubits = 1
qvm.load_program(identity_program)
qvm.kernel()
p = 1 - np.exp(-noise.gate_time_1q / noise.T2)
final_density = np.array([[rho[0, 0], (1 - p) * rho[0, 1]],
[(1 - p) * rho[1, 0], rho[1, 1]]])
assert np.allclose(final_density, qvm._density.todense())
def test_occupation_basis(qvm):
prog = Program().inst([Xgate(0), Xgate(1), Igate(2), Igate(3)])
state = np.zeros(2**4)
state[3] = 1.0
meanfield_state, _ = qvm.wavefunction(prog)
assert np.allclose(meanfield_state.amplitudes, state)