def test_program_subroutine(self, setup_eng, tol):
"""Simple quantum program with a subroutine and references."""
eng, prog = setup_eng(2)
# define some gates
D = ops.Dgate(0.5)
BS = ops.BSgate(0.7 * np.pi, np.pi / 2)
R = ops.Rgate(np.pi / 3)
def subroutine(a, b):
"""Subroutine for the quantum program"""
R | a
BS | (a, b)
R.H | a
# main program
with prog.context as q:
# get register references
alice, bob = q
ops.All(ops.Vacuum()) | (alice, bob)
D | alice
subroutine(alice, bob)
BS | (alice, bob)
subroutine(bob, alice)
state = eng.run(prog).state
# state norm must be invariant
if isinstance(eng.backend, BaseFock):
assert np.allclose(state.trace(), 1, atol=tol, rtol=0)
def test_exceptions(self, state):
"""Test exceptions raised if state prep used on invalid modes"""
G = state()
prog = Program(2)
with prog.context:
# all states act on a single mode
with pytest.raises(ValueError):
G.__or__([0, 1])
# can't repeat the same index
with pytest.raises(RegRefError):
ops.All(G).__or__([0, 0])
def test_interferometer(self, setup_eng, tol):
"""Test applying an interferometer"""
eng, q = setup_eng(3)
with eng:
ops.All(ops.Squeezed(0.5)) | q
init = eng.run()
ops.Interferometer(u1) | q
state = eng.run()
O = np.vstack(
[np.hstack([u1.real, -u1.imag]),
np.hstack([u1.imag, u1.real])])
assert np.allclose(state.cov(), O @ init.cov() @ O.T, atol=tol)
def test_interferometer(self, setup_eng, tol):
"""Test applying an interferometer"""
eng, p1 = setup_eng(3)
with p1.context as q:
ops.All(ops.Squeezed(0.5)) | q
init = eng.run(p1).state
p2 = sf.Program(p1)
with p2.context as q:
ops.Interferometer(u1) | q
state = eng.run(p2).state
O = np.vstack([np.hstack([u1.real, -u1.imag]), np.hstack([u1.imag, u1.real])])
assert np.allclose(state.cov(), O @ init.cov() @ O.T, atol=tol)
def test_passive_gaussian_transform(self, setup_eng, tol):
"""Test applying a passive Gaussian symplectic transform,
which is simply an interferometer"""
eng, q = setup_eng(3)
O = np.vstack(
[np.hstack([u1.real, -u1.imag]),
np.hstack([u1.imag, u1.real])])
with eng:
ops.All(ops.Squeezed(0.5)) | q
init = eng.run()
ops.GaussianTransform(O) | q
state = eng.run()
assert np.allclose(state.cov(), O @ init.cov() @ O.T, atol=tol)
def test_dispatch_one_mode_gates(self, gate):
"""test one mode gates automatically add to the queue"""
prog = sf.Program(2)
G = gate(a)
if G.ns == 2:
pytest.skip("test only for 1 mode gates.")
with prog.context:
G | 0
ops.All(G) | (0, 1)
assert len(prog) == 3
assert all(cmd.op == G for cmd in prog.circuit)
assert prog.circuit[0].reg[0].ind == 0
assert prog.circuit[1].reg[0].ind == 0
assert prog.circuit[2].reg[0].ind == 1
def test_dispatch_one_mode_gates(self, gate):
"""test one mode gates automatically add to the queue"""
eng, _ = sf.Engine(2)
G = gate(a)
if G.ns == 2:
pytest.skip("test only for 1 mode gates.")
with eng:
G | 0
ops.All(G) | (0, 1)
assert len(eng.cmd_queue) == 3
assert all(cmd.op == G for cmd in eng.cmd_queue)
assert eng.cmd_queue[0].reg[0].ind == 0
assert eng.cmd_queue[1].reg[0].ind == 0
assert eng.cmd_queue[2].reg[0].ind == 1
