def adjoint(self):
"""Create a tape that is the adjoint of this one.
Adjointed tapes are the conjugated and transposed version of the
original tapes. Adjointed ops are equivalent to the inverted operation for unitary
gates.
Returns:
~.QuantumTape: the adjointed tape
"""
new_tape = self.copy(copy_operations=True)
qml.transforms.invisible(new_tape.inv)()
# the current implementation of the adjoint
# transform requires that the returned inverted object
# is automatically queued.
QuantumTape._lock.acquire()
try:
QueuingContext.append(new_tape)
except Exception as _:
QuantumTape._lock.release()
raise
QuantumTape._lock.release()
return new_tape
def __enter__(self):
QuantumTape._lock.acquire()
try:
if self.do_queue:
QueuingContext.append(self)
return super().__enter__()
except Exception as _:
QuantumTape._lock.release()
raise
def queue(self):
QueuingContext.append(self, owns=tuple(self.obs))
for o in self.obs:
try:
QueuingContext.update_info(o, owner=self)
except AttributeError:
pass
return self
def _process_queue(self):
super()._process_queue()
for obj, info in self._queue.items():
QueuingContext.append(obj, **info)
# remove the operation recorder from the queuing
# context
QueuingContext.remove(self)
new_tape = self.expand(depth=5, stop_at=lambda obj: not isinstance(obj, QuantumTape))
self.ops = new_tape.operations
self.obs = new_tape.observables
def adjoint(self):
"""Create a tape that is the adjoint of this one.
Adjointed tapes are the conjugated and transposed version of the
original tapes. Adjointed ops are equivalent to the inverted operation for unitary
gates.
Returns:
~.QuantumTape: the adjointed tape
"""
new_tape = self.copy(copy_operations=True)
with qml.tape.stop_recording():
new_tape.inv()
# the current implementation of the adjoint
# transform requires that the returned inverted object
# is automatically queued.
with QuantumTape._lock:
QueuingContext.append(new_tape)
return new_tape
def test_append_no_context(self):
"""Test that append does not fail when no context is present."""
QueuingContext.append(qml.PauliZ(0))