def test_single_qubit_fusion_multiple_qubits(self):
"""Test that all sequences of single-qubit gates across multiple qubits fuse properly."""
def qfunc():
qml.RZ(0.3, wires="a")
qml.RY(0.5, wires="a")
qml.Rot(0.1, 0.2, 0.3, wires="b")
qml.RX(0.1, wires="a")
qml.CNOT(wires=["b", "a"])
qml.SX(wires="b")
qml.S(wires="b")
qml.PhaseShift(0.3, wires="b")
transformed_qfunc = single_qubit_fusion()(qfunc)
original_ops = qml.transforms.make_tape(qfunc)().operations
transformed_ops = qml.transforms.make_tape(
transformed_qfunc)().operations
names_expected = ["Rot", "Rot", "CNOT", "Rot"]
wires_expected = [
Wires("a"), Wires("b"),
Wires(["b", "a"]),
Wires("b")
]
compare_operation_lists(transformed_ops, names_expected,
wires_expected)
# Check matrix representation
matrix_expected = compute_matrix_from_ops_two_qubit(
original_ops, ["a", "b"])
matrix_obtained = compute_matrix_from_ops_two_qubit(
transformed_ops, ["a", "b"])
assert check_matrix_equivalence(matrix_expected, matrix_obtained)
def test_single_qubit_cancelled_fusion(self):
"""Test if a sequence of single-qubit gates that all cancel yields no operations."""
def qfunc():
qml.RZ(0.1, wires=0)
qml.RX(0.2, wires=0)
qml.RX(-0.2, wires=0)
qml.RZ(-0.1, wires=0)
transformed_qfunc = single_qubit_fusion()(qfunc)
transformed_ops = qml.transforms.make_tape(
transformed_qfunc)().operations
assert len(transformed_ops) == 0
def test_single_qubit_fusion_no_gates_after(self):
"""Test that gates with nothing after are applied without modification."""
def qfunc():
qml.RZ(0.1, wires=0)
qml.Hadamard(wires=1)
transformed_qfunc = single_qubit_fusion()(qfunc)
transformed_ops = qml.transforms.make_tape(
transformed_qfunc)().operations
names_expected = ["RZ", "Hadamard"]
wires_expected = [Wires(0), Wires(1)]
compare_operation_lists(transformed_ops, names_expected,
wires_expected)
def test_single_qubit_fusion_not_implemented(self):
"""Test that fusion is correctly skipped for single-qubit gates where
the rotation angles are not specified."""
def qfunc():
qml.RZ(0.1, wires=0)
qml.Hadamard(wires=0)
# No rotation angles specified for PauliRot since it is a gate that
# in principle acts on an arbitrary number of wires.
qml.PauliRot(0.2, "X", wires=0)
qml.RZ(0.1, wires=0)
qml.Hadamard(wires=0)
transformed_qfunc = single_qubit_fusion()(qfunc)
transformed_ops = qml.transforms.make_tape(
transformed_qfunc)().operations
names_expected = ["Rot", "PauliRot", "Rot"]
wires_expected = [Wires(0)] * 3
compare_operation_lists(transformed_ops, names_expected,
wires_expected)
def test_single_qubit_full_fusion(self):
"""Test that a sequence of single-qubit gates all fuse."""
def qfunc():
qml.RZ(0.3, wires=0)
qml.Hadamard(wires=0)
qml.Rot(0.1, 0.2, 0.3, wires=0)
qml.RX(0.1, wires=0)
qml.SX(wires=0)
qml.T(wires=0)
qml.PauliX(wires=0)
transformed_qfunc = single_qubit_fusion()(qfunc)
# Compare matrices
compute_matrix = get_unitary_matrix(qfunc, [0])
matrix_expected = compute_matrix()
compute_transformed_matrix = get_unitary_matrix(transformed_qfunc, [0])
matrix_obtained = compute_transformed_matrix()
assert check_matrix_equivalence(matrix_expected, matrix_obtained)
def test_single_qubit_fusion_exclude_gates(self):
"""Test that fusion is correctly skipped for gates explicitly on an
exclusion list."""
def qfunc():
# Excluded gate at the start
qml.RZ(0.1, wires=0)
qml.Hadamard(wires=0)
qml.PauliX(wires=0)
qml.RZ(0.1, wires=1)
qml.CNOT(wires=[0, 1])
qml.Hadamard(wires=0)
# Excluded gate after another gate
qml.RZ(0.1, wires=0)
qml.PauliX(wires=1)
qml.PauliZ(wires=1)
# Excluded gate after multiple others
qml.RZ(0.2, wires=1)
original_ops = qml.transforms.make_tape(qfunc)().operations
transformed_qfunc = single_qubit_fusion(exclude_gates=["RZ"])(qfunc)
transformed_ops = qml.transforms.make_tape(
transformed_qfunc)().operations
names_expected = [
"RZ", "Rot", "RZ", "CNOT", "Hadamard", "RZ", "Rot", "RZ"
]
wires_expected = ([Wires(0)] * 2 + [Wires(1)] + [Wires([0, 1])] +
[Wires(0)] * 2 + [Wires(1)] * 2)
compare_operation_lists(transformed_ops, names_expected,
wires_expected)
# Compare matrices
compute_matrix = get_unitary_matrix(qfunc, [0, 1])
matrix_expected = compute_matrix()
compute_transformed_matrix = get_unitary_matrix(
transformed_qfunc, [0, 1])
matrix_obtained = compute_transformed_matrix()
assert check_matrix_equivalence(matrix_expected, matrix_obtained)
def test_single_qubit_full_fusion(self):
"""Test that a sequence of single-qubit gates all fuse."""
def qfunc():
qml.RZ(0.3, wires=0)
qml.Hadamard(wires=0)
qml.Rot(0.1, 0.2, 0.3, wires=0)
qml.RX(0.1, wires=0)
qml.SX(wires=0)
qml.T(wires=0)
qml.PauliX(wires=0)
transformed_qfunc = single_qubit_fusion()(qfunc)
original_ops = qml.transforms.make_tape(qfunc)().operations
transformed_ops = qml.transforms.make_tape(
transformed_qfunc)().operations
assert len(transformed_ops) == 1
# Compare matrices
matrix_expected = compute_matrix_from_ops_one_qubit(original_ops)
matrix_obtained = compute_matrix_from_ops_one_qubit(transformed_ops)
assert check_matrix_equivalence(matrix_expected, matrix_obtained)
# Test each of single-qubit, two-qubit, and Rot gates
def qfunc(theta):
qml.Hadamard(wires=0)
qml.RZ(theta[0], wires=0)
qml.PauliY(wires=1)
qml.RZ(theta[1], wires=0)
qml.CNOT(wires=[1, 2])
qml.CRY(theta[2], wires=[1, 2])
qml.PauliZ(wires=0)
qml.CRY(theta[3], wires=[1, 2])
qml.Rot(theta[0], theta[1], theta[2], wires=1)
qml.Rot(theta[2], theta[3], theta[0], wires=1)
return qml.expval(qml.PauliX(0) @ qml.PauliX(2))
transformed_qfunc = single_qubit_fusion()(qfunc)
expected_op_list = ["Rot", "Rot", "CNOT", "CRY", "CRY", "Rot"]
expected_wires_list = [
Wires(0),
Wires(1),
Wires([1, 2]),
Wires([1, 2]),
Wires([1, 2]),
Wires(1)
]
class TestSingleQubitFusionInterfaces:
"""Test that rotation merging works in all interfaces."""
def test_single_qubit_fusion_autograd(self):