def _ml_defaults(hyperparams):
"""Uses hyperparameters or defaults to construct the components of the machine learning benchmark.
Args:
hyperparams (dict): hyperparameters provided by user
"""
# get hyperparameters or set default values
n_features = hyperparams.pop("n_features", 4)
n_samples = hyperparams.pop("n_samples", 20)
interface = hyperparams.pop("interface", "autograd")
diff_method = hyperparams.pop("diff_method", "best")
device = hyperparams.pop("device", "default.qubit")
# if device name is given, create device
if isinstance(device, str):
device = qml.device(device, wires=n_features)
# data
x0 = np.random.normal(loc=-1, scale=1, size=(n_samples // 2, n_features))
x1 = np.random.normal(loc=1, scale=1, size=(n_samples // 2, n_features))
x = np.concatenate([x0, x1], axis=0)
y = np.concatenate([-np.ones(50), np.ones(50)], axis=0)
data = list(zip(x, y))
return data, device, diff_method, interface
def test_wrong_dy_statevector(self, tol, dev):
"""Tests raise an exception when dy is incorrect"""
x, y, z = [0.5, 0.3, -0.7]
with qml.tape.QuantumTape() as tape:
qml.RX(0.4, wires=[0])
qml.Rot(x, y, z, wires=[0])
qml.RY(-0.2, wires=[0])
qml.state()
tape.trainable_params = {1, 2, 3}
dy1 = np.ones(3, dtype=dev.C_DTYPE)
with pytest.raises(
ValueError,
match=
"Size of the provided vector dy must be the same as the size of"
):
dev.vjp(tape.measurements, dy1)
dy2 = np.ones(4, dtype=dev.R_DTYPE)
with pytest.warns(
UserWarning,
match="The vjp method only works with complex-valued dy"):
dev.vjp(tape.measurements, dy2)
def test_calculate_WAW(self):
"""Test that the calculate_WAW method calculates correctly"""
const = 2
A = 0.1767767 * np.ones((4, 4))
params = const * np.ones(4)
waw = StrawberryFieldsGBS.calculate_WAW(params, A)
assert np.allclose(waw, const * A)
def test_caching_samples_at_input(self, mocker):
"""Test caching in non-analytic mode with pre-generated input samples. No call to the
QNode should result in more samples being generated."""
dev = qml.device(
"strawberryfields.gbs",
wires=4,
cutoff_dim=3,
use_cache=True,
shots=4,
samples=samples,
)
A = 0.1767767 * np.ones((4, 4), requires_grad=False)
params = np.ones(4)
@qml.qnode(dev)
def vgbs(params):
ParamGraphEmbed(params, A, 1, wires=range(4))
return qml.probs(wires=range(4))
spy = mocker.spy(sf.Engine, "run")
p1 = vgbs(params)
samps = dev.samples.copy()
p2 = vgbs(0.5 * params)
samps2 = dev.samples.copy()
p2_expected = dev._reparametrize_probability(p1.reshape((3, 3, 3, 3))).ravel()
assert np.allclose(samps, samples)
assert np.allclose(samps2, samples)
assert np.allclose(p2_expected, p2)
spy.assert_not_called()
def test_apply_mask(self):
size = 3
mp = DropoutMask((size, ))
with pytest.raises(IndexError):
mp.apply_mask(pnp.ones((size - 1, size)))
mp.mask[1] = True
result = mp.apply_mask(pnp.ones((size, ), dtype=bool))
assert pnp.sum(mp.mask) == 1
assert pnp.sum(result) == size - 1
def test_generate_hamiltonian(symbols, geometry, h_ref_data):
r"""Test that generate_hamiltonian returns the correct Hamiltonian."""
mol = Molecule(symbols, geometry)
args = []
h = generate_hamiltonian(mol)(*args)
h_ref = qml.Hamiltonian(h_ref_data[0], h_ref_data[1])
assert np.allclose(h.terms[0], h_ref.terms[0])
assert qml.Hamiltonian(np.ones(len(h.terms[0])), h.terms[1]).compare(
qml.Hamiltonian(np.ones(len(h_ref.terms[0])), h_ref.terms[1]))
def test_apply_mask(self):
size = 3
mp = ValueMask((size, ))
with pytest.raises(ValueError):
mp.apply_mask(pnp.ones((size - 1, )))
mp.mask[1] = 1
result = mp.apply_mask(pnp.ones((size, ), dtype=float))
assert pnp.sum(mp.mask) == 1
assert pnp.sum(result) == size + 1
mp.mask[1] = -1
result = mp.apply_mask(pnp.ones((size, ), dtype=float))
assert pnp.sum(result) == size - 1
def test_apply_wrong_dim(self):
"""Test that the apply method raises a ValueError when the number of variable parameters
does not match the number of modes"""
dev = qml.device("strawberryfields.gbs", wires=4, cutoff_dim=3)
op = "ParamGraphEmbed"
wires = list(range(4))
A = 0.1767767 * np.ones((4, 4), requires_grad=False)
params = np.ones(3)
n_mean = 1
par = [params, A, n_mean]
with pytest.raises(ValueError, match="The number of variable parameters must be"):
dev.apply(op, wires, par)
def optimize(alpha, beta):
"""Define a function that optimizes theta_A0, theta_A1, theta_B0, theta_B1 to maximize the probability of winning the game
Args:
- alpha (float): real coefficient of |00>
- beta (float): real coefficient of |11>
Returns:
- (float): Probability of winning
"""
def cost(params):
"""Define a cost function that only depends on params, given alpha and beta fixed"""
return -winning_prob(params, alpha, beta)
# QHACK #
#Initialize parameters, choose an optimization method and number of steps
init_params = np.ones(4)
opt = qml.AdagradOptimizer()
steps = 2000
# QHACK #
# set the initial parameter values
params = init_params
for i in range(steps):
# update the circuit parameters
# QHACK #
params = opt.step(cost, params)
# QHACK #
return winning_prob(params, alpha, beta)
def test_compile_autograd(self, diff_method):
"""Test QNode and gradient in autograd interface."""
original_qnode = qml.QNode(qfunc,
dev,
interface="autograd",
diff_method=diff_method)
transformed_qnode = qml.QNode(transformed_qfunc,
dev,
interface="autograd",
diff_method=diff_method)
x = np.array([0.1, 0.2, 0.3], requires_grad=False)
params = np.ones((2, 3))
# Check that the numerical output is the same
assert qml.math.allclose(original_qnode(x, params),
transformed_qnode(x, params))
# Check that the gradient is the same
assert qml.math.allclose(
qml.grad(original_qnode)(x, params),
qml.grad(transformed_qnode)(x, params))
# Check operation list
ops = transformed_qnode.qtape.operations
compare_operation_lists(ops, expected_op_list, expected_wires_list)
def test_with_qnode(self, qnode, params, ids, nums_frequency, spectra,
shifts, exp_calls, mocker):
"""Run a full reconstruction on a QNode."""
qnode = qml.QNode(qnode, dev_1)
with qml.Tracker(qnode.device) as tracker:
recons = reconstruct(qnode, ids, nums_frequency, spectra,
shifts)(*params)
assert tracker.totals["executions"] == exp_calls
arg_names = list(signature(qnode.func).parameters.keys())
for outer_key in recons:
outer_key_num = arg_names.index(outer_key)
for inner_key, rec in recons[outer_key].items():
x0 = params[outer_key_num]
if not pnp.isscalar(x0):
x0 = x0[inner_key]
shift_vec = qml.math.zeros_like(params[outer_key_num])
shift_vec[inner_key] = 1.0
shift_vec = 1.0 if pnp.isscalar(
params[outer_key_num]) else shift_vec
mask = (0.0 if pnp.isscalar(params[outer_key_num]) else
pnp.ones(qml.math.shape(params[outer_key_num])) -
shift_vec)
univariate = lambda x: qnode(
*params[:outer_key_num],
params[outer_key_num] * mask + x * shift_vec,
*params[outer_key_num + 1:],
)
assert np.isclose(rec(x0), qnode(*params))
assert np.isclose(rec(x0 + 0.1), univariate(x0 + 0.1))
assert fun_close(rec, univariate, 10)
def circuit_aux(cparams):
diag = np.ones(2**num_wires)
diag[0] *= -1
# Initialization
init_circuit(cparams)
# Non-Boolean Amplitude Amplification go brrrrr
for k in range(1, K + 1):
# Act the oracle during odd iterations, or its inverse during
# the even iterations
if k % 2 == 1:
self.oracle(cparams, num_qparams)
else:
qml.inv(self.oracle(cparams, num_qparams))
# Diffusion operator
qml.inv(init_circuit(cparams))
# Evan: This is incredibly painful to implement with a standard
# gate decomposition, so we can't actually use Floq beyond this
# point...
qml.DiagonalQubitUnitary(diag, wires=range(num_wires))
init_circuit(cparams)
# Measurement of the control registers post amplification
return qml.probs(wires=range(self.num_qubits, num_wires))
def diffusion_matrix():
# DO NOT MODIFY anything in this code block
psi_piece = (1 / 2**4) * np.ones(2**4)
ident_piece = np.eye(2**4)
return 2 * psi_piece - ident_piece
def test_compile_template(self):
"""Test that functions with templates are correctly expanded and compiled."""
# Push commuting gates to the right and merging rotations gives a circuit
# with alternating RX and CNOT gates
def qfunc(x, params):
qml.templates.AngleEmbedding(x, wires=range(3))
qml.templates.BasicEntanglerLayers(params, wires=range(3))
return qml.expval(qml.PauliZ(wires=2))
dev = qml.device("default.qubit", wires=3)
qnode = qml.QNode(qfunc, dev)
pipeline = [commute_controlled, merge_rotations]
transformed_qfunc = compile(pipeline=pipeline)(qfunc)
transformed_qnode = qml.QNode(transformed_qfunc, dev)
x = np.array([0.1, 0.2, 0.3])
params = np.ones((2, 3))
original_result = qnode(x, params)
transformed_result = transformed_qnode(x, params)
assert np.allclose(original_result, transformed_result)
names_expected = ["RX", "CNOT"] * 6
wires_expected = [
Wires(0),
Wires([0, 1]),
Wires(1),
Wires([1, 2]),
Wires(2),
Wires([2, 0]),
] * 2
compare_operation_lists(transformed_qnode.qtape.operations, names_expected, wires_expected)
def test_apply_mask(self):
size = 3
mp = self._create_circuit(size)
with pytest.raises(ValueError):
mp.apply_mask(pnp.ones((size, size - 1)))
mp.mask(Axis.WIRES)[:size - 1] = True
result = mp.apply_mask(pnp.ones((size, size), dtype=bool))
assert pnp.sum(~mp.full_mask(DropoutMask)) == size
assert pnp.sum(result) == size
mp.mask(Axis.LAYERS)[:size - 1] = True
result = mp.apply_mask(pnp.ones((size, size), dtype=bool))
assert pnp.sum(~mp.full_mask(DropoutMask)) == 1
assert pnp.sum(result) == 1
mp.mask(Axis.PARAMETERS)[(size - 1, size - 1)] = True
result = mp.apply_mask(pnp.ones((size, size), dtype=bool))
assert pnp.sum(~mp.full_mask(DropoutMask)) == 0
assert pnp.sum(result) == 0
def test_reparametrize_probability(self):
"""Test the _reparametrize_probability method applied to a fixed 2-mode example"""
dev = qml.device("strawberryfields.gbs", wires=2, cutoff_dim=3, shots=None)
A = 0.35355339 * np.ones((2, 2))
dev._WAW = 0.9 * A
dev.Z_inv = 1 / np.sqrt(2)
dev._params = 0.9 * np.ones(2)
p = np.array(
[0.70710678, 0.0, 0.04419417, 0.0, 0.08838835, 0.0, 0.04419417, 0.0, 0.02485922]
).reshape((3, 3))
p_reparam = dev._reparametrize_probability(p)
p_target = np.array(
[0.77136243, 0.0, 0.03905022, 0.0, 0.07810045, 0.0, 0.03905022, 0.0, 0.01779226]
).reshape((3, 3))
assert np.allclose(p_reparam, p_target)
def test_jacobian_all_wires(self):
"""Test that the _jacobian_all_wires method returns the correct jacobian for a fixed
input probability distribution"""
dev = qml.device("strawberryfields.gbs", wires=4, cutoff_dim=3)
dev._WAW = 0.1767767 * np.ones((4, 4))
params = np.array([1, 2, 3, 4])
n_mean = np.ones(4) / 4
dev._params = params
indices = np.indices([3, 3, 3, 3]).reshape(4, -1).T
probs = np.arange(3 ** 4)
jac_expected = np.zeros((3 ** 4, 4))
for i, ind in enumerate(indices):
jac_expected[i] = probs[i] * (ind - n_mean) / params
jac = dev._jacobian_all_wires(probs)
assert np.allclose(jac, jac_expected)
def test_apply_analytic(self):
"""Test that the apply method constructs the correct program"""
dev = qml.device("strawberryfields.gbs", wires=4, cutoff_dim=3)
op = "ParamGraphEmbed"
wires = list(range(4))
A = 0.1767767 * np.ones((4, 4), requires_grad=False)
params = 0.5 * np.ones(4)
n_mean = 1
par = [params, A, n_mean]
with dev.execution_context():
dev.apply(op, wires, par)
circ = dev.prog.circuit
assert len(circ) == 1
assert isinstance(circ[0].op, GraphEmbed)
assert np.allclose(circ[0].op.p[0], 0.5 * A)
def oracle(self, cparams, num_qparams):
diag = np.ones(2**self.num_qubits)
diag[0] *= -1
qml.inv(self.rand_circuit(cparams, num_qparams))
qml.DiagonalQubitUnitary(diag, wires=range(self.num_qubits))
self.rand_circuit(cparams, num_qparams)
qml.DiagonalQubitUnitary(diag, wires=range(self.num_qubits))
def test_pre_measure_eng(self, tol):
"""Test that the pre_measure method operates as expected by initializing the engine
correctly"""
dev = qml.device("strawberryfields.gbs", wires=4, cutoff_dim=3)
prog = Program(4)
op1 = GraphEmbed(0.1767767 * np.ones((4, 4)), mean_photon_per_mode=0.25)
prog.append(op1, prog.register)
dev.prog = prog
dev.pre_measure()
assert dev.eng.backend_name == "gaussian"
assert dev.eng.backend_options == {"cutoff_dim": 3}
def test_shape(self, wires, cutoff_dim):
"""Test that the probabilities and jacobian are returned with the expected shape"""
dev = qml.device("strawberryfields.gbs", wires=wires, cutoff_dim=cutoff_dim)
a = np.ones((wires, wires), requires_grad=False)
params = np.ones(wires)
@qnode_decorator(dev)
def vgbs(params):
ParamGraphEmbed(params, a, 1, wires=range(wires))
return qml.probs(wires=range(wires))
d_vgbs = qml.jacobian(vgbs, argnum=0)
p = vgbs(params)
dp = d_vgbs(params)
assert p.shape == (cutoff_dim ** wires,)
assert dp.shape == (cutoff_dim ** wires, wires)
assert (p >= 0).all()
assert (p <= 1).all()
assert np.sum(p) <= 1
def test_template_integration(self, strategy, tol):
"""Test that the metric tensor transform acts on QNodes
correctly when the QNode contains a template"""
dev = qml.device("default.qubit", wires=3)
@qml.beta.qnode(dev, expansion_strategy=strategy)
def circuit(weights):
qml.templates.StronglyEntanglingLayers(weights, wires=[0, 1, 2])
return qml.probs(wires=[0, 1])
weights = np.ones([2, 3, 3], dtype=np.float64, requires_grad=True)
res = qml.metric_tensor(circuit, approx="block-diag")(weights)
assert res.shape == (2, 3, 3, 2, 3, 3)
def test_pre_measure_non_analytic_cache(self, mocker):
"""Test that the pre_measure method does not overwrite existing samples if present in
non-analytic mode when use_cache is ``True``"""
samples = -1 * np.ones((10, 4))
dev = qml.device(
"strawberryfields.gbs",
wires=4,
cutoff_dim=3,
shots=10,
samples=samples,
use_cache=True,
)
prog = Program(4)
op1 = GraphEmbed(0.1767767 * np.ones((4, 4)), mean_photon_per_mode=0.25)
op2 = MeasureFock()
prog.append(op1, prog.register)
prog.append(op2, prog.register)
dev.prog = prog
dev.pre_measure()
spy = mocker.spy(sf.Engine, "run")
assert np.allclose(dev.samples, samples)
spy.assert_not_called()
def test_pre_measure_state_and_samples(self, tol):
"""Test that the pre_measure method operates as expected in analytic mode by generating the
correct output state and not generating samples"""
dev = qml.device("strawberryfields.gbs", wires=4, cutoff_dim=3)
prog = Program(4)
op1 = GraphEmbed(0.1767767 * np.ones((4, 4)), mean_photon_per_mode=0.25)
prog.append(op1, prog.register)
dev.prog = prog
dev.pre_measure()
assert np.allclose(dev.state.displacement(), np.zeros(4))
assert np.allclose(dev.state.cov(), target_cov, atol=tol)
assert dev.samples.size == 0
def test_shape_reduced_wires(self, wires, cutoff_dim):
"""Test that the probabilities and jacobian are returned with the expected shape when
probabilities are measured on a subset of wires"""
dev = qml.device("strawberryfields.gbs", wires=wires, cutoff_dim=cutoff_dim)
a = np.ones((wires, wires))
params = np.ones(wires)
@qml.qnode(dev)
def vgbs(params):
ParamGraphEmbed(params, a, 1, wires=range(wires))
return qml.probs(wires=[0, 1])
d_vgbs = qml.jacobian(vgbs, argnum=0)
p = vgbs(params)
dp = d_vgbs(params)
assert p.shape == (cutoff_dim ** 2,)
assert dp.shape == (cutoff_dim ** 2, wires)
assert (p >= 0).all()
assert (p <= 1).all()
assert np.sum(p) <= 1
def test_custom_rotation(self, rotation):
"""Tests that non-default rotation gates are used correctly."""
n_layers = 2
n_wires = 4
weights = np.ones(shape=(n_layers, n_wires))
with pennylane._queuing.OperationRecorder() as rec:
BasicEntanglerLayers(weights, wires=range(n_wires), rotation=rotation)
# assert queue contains the custom rotations and CNOTs only
gates = rec.queue
for op in gates:
if not isinstance(op, CNOT):
assert isinstance(op, rotation)
def test_pre_measure_state_and_samples_non_analytic(self, tol):
"""Test that the pre_measure method operates as expected in non-analytic mode by
generating the correct output state and samples of the right shape"""
dev = qml.device("strawberryfields.gbs", wires=4, cutoff_dim=3, analytic=False, shots=2)
prog = Program(4)
op1 = GraphEmbed(0.1767767 * np.ones((4, 4)), mean_photon_per_mode=0.25)
op2 = MeasureFock()
prog.append(op1, prog.register)
prog.append(op2, prog.register)
dev.prog = prog
dev.pre_measure()
assert np.allclose(dev.state.displacement(), np.zeros(4))
assert np.allclose(dev.state.cov(), target_cov, atol=tol)
assert dev.samples.shape == (2, 4)
def test_caching_samples(self, mocker):
"""Test caching in non-analytic mode. Samples should be generated upon first call and
then not generated subsequently."""
dev = qml.device(
"strawberryfields.gbs", wires=4, cutoff_dim=3, use_cache=True, shots=10
)
A = 0.1767767 * np.ones((4, 4), requires_grad=False)
params = np.ones(4)
@qml.qnode(dev)
def vgbs(params):
ParamGraphEmbed(params, A, 1, wires=range(4))
return qml.probs(wires=range(4))
vgbs(params)
samps = dev.samples.copy()
circ = dev.prog.circuit
assert np.allclose(circ[0].op.p[0], A)
spy = mocker.spy(sf.Engine, "run")
vgbs(0.5 * params)
samps2 = dev.samples.copy()
assert np.allclose(samps, samps2)
spy.assert_not_called()
def oracle(self, cparams, num_qparams):
diag = np.ones(2**self.num_qubits)
diag[0] *= -1
qml.inv(self.rand_circuit(cparams, num_qparams))
if self.floq:
decomposed_oracle(self.num_qubits)
else:
qml.DiagonalQubitUnitary(diag, wires=range(self.num_qubits))
self.rand_circuit(cparams, num_qparams)
if self.floq:
decomposed_oracle(self.num_qubits)
else:
qml.DiagonalQubitUnitary(diag, wires=range(self.num_qubits))
def test_apply_non_analytic(self, use_cache):
"""Test that the apply method constructs the correct program when in non-analytic mode"""
dev = qml.device(
"strawberryfields.gbs", wires=4, cutoff_dim=3, shots=100, use_cache=use_cache
)
op = "ParamGraphEmbed"
wires = list(range(4))
A = 0.1767767 * np.ones((4, 4), requires_grad=False)
params = 0.5 * np.ones(4)
n_mean = 1
par = [params, A, n_mean]
with dev.execution_context():
dev.apply(op, wires, par)
circ = dev.prog.circuit
assert len(circ) == 2
assert isinstance(circ[0].op, GraphEmbed)
if use_cache:
assert np.allclose(circ[0].op.p[0], A)
else:
assert np.allclose(circ[0].op.p[0], 0.5 * A)
assert isinstance(circ[1].op, MeasureFock)