Qiskit IBMQ Provider 0.4.0

Added

• A new IBMQJobManager class that takes a list of circuits or pulse schedules
  as input, splits them into one or more jobs, and submits the jobs.
  (#389, #400, #407)
• New features to provider.backends:
  • it contains the available backends as attributes. A user can now use
    provider.backends.<tab> to see a list of backend names, and make
    use of the attributes as regular IBMQBackend instances. (#303)
  • the methods provider.backends.jobs() and
    provider.backends.retrieve_job() can be used for retrieving
    provider-wide jobs. (#354)

Changed

• IBMQBackend.run() now accepts an optional job_name parameter. If
  specified, the job_name is assigned to the job, which can also be used
  as a filter in IBMQBackend.jobs(). (#300, #384)
• IBMQBackend.run() now accepts an optional job_share_level
  parameter. If specified, the job could be shared with other users at the
  global, hub, group, project, or none level. (#414)
• The signature of IBMQBackend.jobs() is changed. db_filter, which was the
  4th parameter, is now the 5th parameter. (#300)
• The backend.properties() function now accepts an optional datetime
  parameter. If specified, the function returns the backend properties closest
  to, but older than, the specified datetime filter. (#277)
• The WebsocketClient.get_job_status() method now accepts two optional
  parameters: retries and backoff_factor. (#341)
• The IBMQJob class has been refactored:
  • The IBMQJob attributes are now automatically populated based on the
    information contained in the remote API. As a result, the IBMQJob
    constructor signature has changed. (#329)
  • IBMQJob.submit() can no longer be called directly, and jobs are expected
    to be submitted via IBMQBackend.run(). (#329)
  • IBMQJob.error_message() now gives more information on why a job failed.
    (#375)
  • IBMQJob.queue_position() now accepts an optional refresh parameter that
    indicates whether it should query the API for the latest queue position.
    (#387)
  • The IBMQJob.result() function now accepts an optional partial parameter.
    If specified, IBMQJob.result() will return partial results for jobs with
    experiments that failed. (#399)
• The Exception hierarchy has been refined with more specialized classes, and
  exception chaining is used in some cases - please inspect the complete
  traceback for more informative failures. (#395, #396)
• Some warnings have been toned down to logger.warning messages. (#379)

Removed

• Support for the legacy Quantum Experience and QConsole is fully deprecated.
  Only credentials from the new Quantum Experience can be used. (#344)
• The circuits functionality has been temporarily removed from the provider. It
  will be reintroduced in future versions. (#429)