IBMCircuitJob
IBMCircuitJob(backend, api_client, job_id, creation_date=None, status=None, runtime_client=None, kind=None, name=None, time_per_step=None, result=None, error=None, session_id=None, tags=None, run_mode=None, client_info=None, **kwargs)
Representation of a job that executes on an IBM Quantum backend.
The job may be executed on a simulator or a real device. A new IBMCircuitJob instance is returned when you call IBMBackend.run() to submit a job to a particular backend.
If the job is successfully submitted, you can inspect the job’s status by calling status(). Job status can be one of the JobStatus members. For example:
from qiskit.providers.jobstatus import JobStatus
job = backend.run(...)
try:
job_status = job.status() # Query the backend server for job status.
if job_status is JobStatus.RUNNING:
print("The job is still running")
except IBMJobApiError as ex:
print("Something wrong happened!: {}".format(ex))An error may occur when querying the remote server to get job information. The most common errors are temporary network failures and server errors, in which case an IBMJobApiError is raised. These errors usually clear quickly, so retrying the operation is likely to succeed.
Some of the methods in this class are blocking, which means control may not be returned immediately. result() is an example of a blocking method:
job = backend.run(...)
try:
job_result = job.result() # It will block until the job finishes.
print("The job finished with result {}".format(job_result))
except JobError as ex:
print("Something wrong happened!: {}".format(ex))Job information retrieved from the server is attached to the IBMCircuitJob instance as attributes. Given that Qiskit and the server can be updated independently, some of these attributes might be deprecated or experimental. Supported attributes can be retrieved via methods. For example, you can use creation_date() to retrieve the job creation date, which is a supported attribute.
IBMCircuitJob constructor.
Parameters
- backend (
IBMBackend) – The backend instance used to run this job. - api_client (
AccountClient) – Object for connecting to the server. - job_id (
str) – Job ID. - creation_date (
Optional[str]) – Job creation date. - status (
Optional[str]) – Job status returned by the server. - runtime_client (
Optional[RuntimeClient]) – Object for connecting to the runtime server - kind (
Optional[str]) – Job type. - name (
Optional[str]) – Job name. - time_per_step (
Optional[dict]) – Time spent for each processing step. - result (
Optional[dict]) – Job result. - error (
Optional[dict]) – Job error. - tags (
Optional[List[str]]) – Job tags. - run_mode (
Optional[str]) – Scheduling mode the job runs in. - client_info (
Optional[Dict[str,str]]) – Client information from the API. - kwargs (
Any) – Additional job attributes.
Attributes
client_version
Return version of the client used for this job.
Return type
Dict[str, str]
Returns
Client version in dictionary format, where the key is the name
of the client and the value is the version.
usage_estimation
Return usage estimation information for this job.
Return type
Dict[str, Any]
Returns
quantum_seconds which is the estimated quantum time of the job in seconds. Quantum time represents the time that the QPU complex is occupied exclusively by the job.
version
= 1
Methods
backend
backend()
backend_options
backend_options()
Return the backend configuration options used for this job.
Options that are not applicable to the job execution are not returned. Some but not all of the options with default values are returned. You can use qiskit_ibm_provider.IBMBackend.options to see all backend options.
Return type
Dict
Returns
Backend options used for this job. An empty dictionary is returned if the options cannot be retrieved.
cancel
cancel()
Attempt to cancel the job.
Depending on the state the job is in, it might be impossible to cancel the job.
Return type
bool
Returns
True if the job is cancelled, else False.
Raises
- IBMJobInvalidStateError – If the job is in a state that cannot be cancelled.
- IBMJobError – If unable to cancel job.
cancelled
cancelled()
Return whether the job has been cancelled.
Return type
bool
circuits
circuits()
Return the circuits for this job.
Return type
List[QuantumCircuit]
Returns
The circuits or for this job. An empty list is returned if the circuits cannot be retrieved (for example, if the job uses an old format that is no longer supported).
creation_date
creation_date()
Return job creation date, in local time.
Return type
datetime
Returns
The job creation date as a datetime object, in local time.
done
done()
Return whether the job has successfully run.
Return type
bool
error_message
error_message()
Provide details about the reason of failure.
Return type
Optional[str]
Returns
An error report if the job failed or None otherwise.
header
header()
Return the user header specified for this job.
Return type
Dict
Returns
User header specified for this job. An empty dictionary is returned if the header cannot be retrieved.
in_final_state
in_final_state()
Return whether the job is in a final job state such as DONE or ERROR.
Return type
bool
job_id
job_id()
Return the job ID assigned by the server.
Return type
str
Returns
Job ID.
name
name()
Return the name assigned to this job.
Return type
Optional[str]
Returns
Job name or None if no name was assigned to this job.
properties
properties(refresh=False)
Return the backend properties for this job.
Parameters
refresh (bool) – If True, re-query the server for the backend properties. Otherwise, return a cached version.
Return type
Optional[BackendProperties]
Returns
The backend properties used for this job, at the time the job was run, or None if properties are not available.
queue_info
queue_info()
Return queue information for this job.
The queue information may include queue position, estimated start and end time, and dynamic priorities for the hub, group, and project. See QueueInfo for more information.
The queue information is calculated after the job enters the queue. Therefore, some or all of the information may not be immediately available, and this method may return None.
Return type
Optional[QueueInfo]
Returns
A QueueInfo instance that contains queue information for this job, or None if queue information is unknown or not applicable.
queue_position
queue_position(refresh=False)
Return the position of the job in the server queue.
The position returned is within the scope of the provider and may differ from the global queue position.
Parameters
refresh (bool) – If True, re-query the server to get the latest value. Otherwise return the cached value.
Return type
Optional[int]
Returns
Position in the queue or None if position is unknown or not applicable.
refresh
refresh()
Obtain the latest job information from the server.
This method may add additional attributes to this job instance, if new information becomes available.
Raises
IBMJobApiError – If an unexpected error occurred when communicating with the server.
Return type
None
result
result(timeout=None, refresh=False)
Return the result of the job.
Some IBM Quantum job results can only be read once. A second attempt to query the server for the same job will fail, since the job has already been “consumed”.
The first call to this method in an IBMCircuitJob instance will query the server and consume any available job results. Subsequent calls to that instance’s result() will also return the results, since they are cached. However, attempting to retrieve the results again in another instance or session might fail due to the job results having been consumed.
When partial=True, this method will attempt to retrieve partial results of failed jobs. In this case, precaution should be taken when accessing individual experiments, as doing so might cause an exception. The success attribute of the returned Result instance can be used to verify whether it contains partial results.
For example, if one of the experiments in the job failed, trying to get the counts of the unsuccessful experiment would raise an exception since there are no counts to return:
try:
counts = result.get_counts("failed_experiment")
except QiskitError:
print("Experiment failed!")If the job failed, you can use error_message() to get more information.
Parameters
- timeout (
Optional[float]) – Number of seconds to wait for job. - refresh (
bool) – IfTrue, re-query the server for the result. Otherwise return the cached value.
Return type
Returns
Job result.
Raises
- IBMJobInvalidStateError – If the job was cancelled.
- IBMJobFailureError – If the job failed.
- IBMJobApiError – If an unexpected error occurred when communicating with the server.
running
running()
Return whether the job is actively running.
Return type
bool
scheduling_mode
scheduling_mode()
Return the scheduling mode the job is in.
Return type
Optional[str]
Returns
The scheduling mode the job is in or None if the information is not available.
status
status()
Query the server for the latest job status.
This method is not designed to be invoked repeatedly in a loop for an extended period of time. Doing so may cause the server to reject your request. Use wait_for_final_state() if you want to wait for the job to finish.
If the job failed, you can use error_message() to get more information.
Return type
Returns
The status of the job.
Raises
IBMJobApiError – If an unexpected error occurred when communicating with the server.
submit
submit()
Unsupported method.
This method is not supported, please use run() to submit a job.
Raises
NotImplementedError – Upon invocation.
Return type
None
tags
tags()
Return the tags assigned to this job.
Return type
List[str]
Returns
Tags assigned to this job.
time_per_step
time_per_step()
Return the date and time information on each step of the job processing.
The output dictionary contains the date and time information on each step of the job processing, in local time. The keys of the dictionary are the names of the steps, and the values are the date and time data, as a datetime object with local timezone info. For example:
{'CREATING': datetime(2020, 2, 13, 15, 19, 25, 717000, tzinfo=tzlocal(),
'CREATED': datetime(2020, 2, 13, 15, 19, 26, 467000, tzinfo=tzlocal(),
'VALIDATING': datetime(2020, 2, 13, 15, 19, 26, 527000, tzinfo=tzlocal()}Return type
Optional[Dict]
Returns
Date and time information on job processing steps, in local time, or None if the information is not yet available.
update_name
update_name(name)
Update the name associated with this job.
Parameters
name (str) – The new name for this job.
Return type
str
Returns
The new name associated with this job.
update_tags
update_tags(new_tags)
Update the tags associated with this job.
Parameters
new_tags (List[str]) – New tags to assign to the job.
Return type
List[str]
Returns
The new tags associated with this job.
Raises
- IBMJobApiError – If an unexpected error occurred when communicating with the server or updating the job tags.
- IBMJobInvalidStateError – If none of the input parameters are specified or if any of the input parameters are invalid.
wait_for_final_state
wait_for_final_state(timeout=None, wait=3)
Use the websocket server to wait for the final the state of a job. The server
will remain open if the job is still running and the connection will be terminated once the job completes. Then update and return the status of the job.
Parameters
timeout (Optional[float]) – Seconds to wait for the job. If None, wait indefinitely.
Raises
IBMJobTimeoutError – If the job does not complete within given timeout.
Return type
None