def _add_layer(self, gate: gates.Gate):
"""Called automatically by `add` when `gate` is measurement."""
gate.prepare()
for unitary in gate.unitaries:
self.set_nqubits(unitary)
self.queue.append(unitary)
if gate.additional_unitary is not None:
self.set_nqubits(gate.additional_unitary)
self.queue.append(gate.additional_unitary)
def _add(self, gate: gates.Gate):
if gate.density_matrix and not self.density_matrix:
raise_error(
ValueError, "Cannot add {} on circuits that uses state "
"vectors. Please switch to density matrix "
"circuit.".format(gate.name))
elif self.density_matrix:
gate.density_matrix = True
if self._final_state is not None:
raise_error(
RuntimeError, "Cannot add gates to a circuit after it is "
"executed.")
for q in gate.target_qubits:
if q >= self.nqubits:
raise_error(
ValueError, "Attempting to add gate with target qubits {} "
"on a circuit of {} qubits."
"".format(gate.target_qubits, self.nqubits))
self.check_measured(gate.qubits)
if isinstance(gate, gates.M):
self._add_measurement(gate)
elif isinstance(gate, gates.VariationalLayer):
self._add_layer(gate)
else:
self.set_nqubits(gate)
self.queue.append(gate)
if isinstance(gate, gates.UnitaryChannel):
self.repeated_execution = not self.density_matrix
if isinstance(gate, gates.ParametrizedGate):
self.parametrized_gates.append(gate)
if gate.trainable:
self.trainable_gates.append(gate)
def _add(self, gate: gates.Gate):
"""Adds a gate in the circuit (inherited from :class:`qibo.base.circuit.BaseCircuit`).
Also checks that there are sufficient qubits to use as global.
"""
if not isinstance(gate, gate_module.TensorflowGate):
raise_error(
NotImplementedError, "Distributed circuit does not support "
"native tensorflow gates.")
if isinstance(gate, gates.VariationalLayer):
gate._prepare()
elif (self.nqubits - len(gate.target_qubits) < self.nglobal
and not isinstance(gate, gates.M)):
raise_error(
ValueError, "Insufficient qubits to use for global in "
"distributed circuit.")
super(TensorflowDistributedCircuit, self)._add(gate)
def _add_measurement(self, gate: gates.Gate):
"""Called automatically by `add` when `gate` is measurement.
This is because measurement gates (`gates.M`) are treated differently
than all other gates.
The user is not supposed to use the `add_measurement` method.
"""
# Set register's name and log the set of qubits in `self.measurement_tuples`
name = gate.register_name
if name is None:
name = "register{}".format(len(self.measurement_tuples))
gate.register_name = name
elif name in self.measurement_tuples:
raise_error(
KeyError, "Register name {} has already been used."
"".format(name))
# Update circuit's global measurement gate
if self.measurement_gate is None:
self.measurement_gate = gate
self.measurement_tuples[name] = tuple(gate.target_qubits)
else:
self.measurement_gate.add(gate)
self.measurement_tuples[name] = gate.target_qubits