def _make_random_change(self, compiled_sequence: UnitarySequence) -> None:
'''
Chooses and implements a random change to the specified
unitary sequence.
'''
count_append = np.count_nonzero([
CompilerAction.is_append(action) for action in list(CompilerAction)
])
count_non_append = len(CompilerAction) - count_append
p_append = self.append_probability / count_append
p_non_append = (1 - self.append_probability) / count_non_append
action = np.random.choice(
list(CompilerAction),
1,
p=[
p_append if CompilerAction.is_append(action) else p_non_append
for action in list(CompilerAction)
])
new_sequence_entry = None
if CompilerAction.is_append(action):
new_sequence_entry = Compiler.create_random_sequence_entry(
self.dimension, self.unitary_primitives,
self.unitary_primitive_probabilities)
if action == CompilerAction.AppendFirst:
compiled_sequence.append_first(new_sequence_entry)
elif action == CompilerAction.AppendLast:
compiled_sequence.append_last(new_sequence_entry)
elif action == CompilerAction.RemoveFirst:
compiled_sequence.remove_first()
elif action == CompilerAction.RemoveLast:
compiled_sequence.remove_last()
def test_append_and_remove(self) -> None:
dimension = 2
identity = Unitary.identity(dimension)
sequence = UnitarySequence(dimension)
assert sequence.get_length() == 0
assert sequence.product().close_to(identity)
sequence.append_first(
UnitarySequenceEntry(UnitaryDefinitions.sigmax(), [0]))
assert sequence.get_length() == 1
assert sequence.product().close_to(UnitaryDefinitions.sigmax())
sequence.append_last(
UnitarySequenceEntry(UnitaryDefinitions.sigmay(), [0]))
assert sequence.get_length() == 2
assert sequence.product().close_to(UnitaryDefinitions.sigmaz())
sequence.append_first(
UnitarySequenceEntry(UnitaryDefinitions.sigmaz(), [0]))
assert sequence.get_length() == 3
assert sequence.product().close_to(identity)
sequence.remove_last()
assert sequence.get_length() == 2
assert sequence.product().close_to(UnitaryDefinitions.sigmay())
sequence.remove_first()
assert sequence.get_length() == 1
assert sequence.product().close_to(UnitaryDefinitions.sigmax())
sequence.remove_first()
assert sequence.get_length() == 0
assert sequence.product().close_to(identity)
def _make_random_change_layered(
self, compiled_sequence: UnitarySequence,
unitary_primitive_counts: Dict[UnitaryPrimitive, int]) -> None:
'''
Chooses and implements a random change to the specified
layered unitary sequence.
'''
count_append = np.count_nonzero([
CompilerAction.is_append(action) for action in list(CompilerAction)
])
count_non_append = len(CompilerAction) - count_append
p_append = self.append_probability / count_append
p_non_append = (1 - self.append_probability) / count_non_append
action = np.random.choice(
list(CompilerAction),
1,
p=[
p_append if CompilerAction.is_append(action) else p_non_append
for action in list(CompilerAction)
])
layer_length = sum(unitary_primitive_counts.values())
new_layer = None
if CompilerAction.is_append(action):
new_layer = Compiler.create_random_layer(self.dimension,
unitary_primitive_counts)
# only save the undo state for the first modification to the sequence
# this is so that a future undo() call will reverse the entire action
if action == CompilerAction.AppendFirst:
for i, sequence_entry in enumerate(new_layer):
compiled_sequence.append_first(sequence_entry,
save_undo=(i == 0))
elif action == CompilerAction.AppendLast:
for i, sequence_entry in enumerate(new_layer):
compiled_sequence.append_last(sequence_entry,
save_undo=(i == 0))
elif action == CompilerAction.RemoveFirst:
for i in range(layer_length):
compiled_sequence.remove_first(save_undo=(i == 0))
elif action == CompilerAction.RemoveLast:
for i in range(layer_length):
compiled_sequence.remove_last(save_undo=(i == 0))
def test_undo(self) -> None:
dimension = 2
identity = Unitary.identity(dimension)
sequence = UnitarySequence(dimension)
assert sequence.get_length() == 0
with pytest.raises(Exception):
sequence.undo()
sequence.append_first(
UnitarySequenceEntry(UnitaryDefinitions.sigmax(), [0]))
assert sequence.get_length() == 1
assert sequence.product().close_to(UnitaryDefinitions.sigmax())
sequence.undo()
assert sequence.get_length() == 0
assert sequence.product().close_to(identity)
with pytest.raises(Exception):
sequence.undo()
sequence.append_first(
UnitarySequenceEntry(UnitaryDefinitions.sigmay(), [0]))
sequence.append_first(
UnitarySequenceEntry(UnitaryDefinitions.sigmay(), [0]))
assert sequence.get_length() == 2
assert sequence.product().close_to(identity)
sequence.remove_last()
assert sequence.get_length() == 1
assert sequence.product().close_to(UnitaryDefinitions.sigmay())
sequence.undo()
assert sequence.get_length() == 2
assert sequence.product().close_to(identity)
with pytest.raises(Exception):
sequence.undo()