def state_vector() -> ResultType:
"""Registers this function into the circuit class.
Returns:
ResultType: state vector as a requested result type
Examples:
>>> circ = Circuit().state_vector()
"""
return ResultType.StateVector()
def _get_result(completed_task: Union[AwsQuantumTask, LocalQuantumTask],
want_state: bool) -> Dict[str, BackendResult]:
result = completed_task.result()
kwargs = {}
if want_state:
kwargs["state"] = result.get_value_by_result_type(
ResultType.StateVector())
else:
kwargs["shots"] = OutcomeArray.from_readouts(result.measurements)
return {"result": BackendResult(**kwargs)}
def process_circuits(
self,
circuits: Iterable[Circuit],
n_shots: Optional[int] = None,
valid_check: bool = True,
**kwargs: KwargTypes,
) -> List[ResultHandle]:
"""
Supported `kwargs`: none
"""
if not self.supports_shots and not self.supports_state:
raise RuntimeError("Backend does not support shots or state")
if n_shots is None:
n_shots = 0
want_state = n_shots == 0
if (not want_state) and (n_shots < self._sample_min_shots
or n_shots > self._sample_max_shots):
raise ValueError(
"For sampling, n_shots must be between "
f"{self._sample_min_shots} and {self._sample_max_shots}. "
"For statevector simulation, omit this parameter.")
if valid_check:
self._check_all_circuits(circuits, nomeasure_warn=False)
handles = []
for circ in circuits:
bkcirc = self._to_bkcirc(circ)
if want_state:
bkcirc.add_result_type(ResultType.StateVector())
if not bkcirc.instructions and len(circ.bits) == 0:
task = None
else:
task = self._run(bkcirc, n_shots=n_shots)
if self._device_type == _DeviceType.LOCAL:
# Results are available now. Put them in the cache.
if task is not None:
assert task.state() == "COMPLETED"
results = _get_result(task, want_state)
else:
results = {
"result": self.empty_result(circ, n_shots=n_shots)
}
else:
# Task is asynchronous. Must wait for results.
results = {}
if task is not None:
handle = ResultHandle(task.id, want_state)
else:
handle = ResultHandle(str(uuid4()), False)
self._cache[handle] = results
handles.append(handle)
return handles