qiskit.providers.BackendV1
class BackendV1(configuration, provider=None, **fields)
Abstract class for Backends
This abstract class is to be used for all Backend objects created by a provider. There are several classes of information contained in a Backend. The first are the attributes of the class itself. These should be used to defined the immutable characteristics of the backend. The options
attribute of the backend is used to contain the dynamic user configurable options of the backend. It should be used more for runtime options that configure how the backend is used. For example, something like a shots
field for a backend that runs experiments which would contain an int for how many shots to execute. The properties
attribute is optionally defined BackendProperties
object and is used to return measured properties, or properties of a backend that may change over time. The simplest example of this would be a version string, which will change as a backend is updated, but also could be something like noise parameters for backends that run experiments.
This first version of the Backend abstract class is written to be mostly backwards compatible with the legacy providers interface. This includes reusing the model objects BackendProperties
and BackendConfiguration
. This was done to ease the transition for users and provider maintainers to the new versioned providers. Expect, future versions of this abstract class to change the data model and interface.
Initialize a backend class
Parameters
- configuration (BackendConfiguration) – A backend configuration object for the backend object.
- provider (qiskit.providers.Provider) – Optionally, the provider object that this Backend comes from.
- fields – kwargs for the values to use to override the default options.
Raises
AttributeError – if input field not a valid options
__init__
__init__(configuration, provider=None, **fields)
Initialize a backend class
Parameters
- configuration (BackendConfiguration) – A backend configuration object for the backend object.
- provider (qiskit.providers.Provider) – Optionally, the provider object that this Backend comes from.
- fields – kwargs for the values to use to override the default options.
Raises
AttributeError – if input field not a valid options
Methods
__init__ (configuration[, provider]) | Initialize a backend class |
configuration () | Return the backend configuration. |
name () | Return the backend name. |
properties () | Return the backend properties. |
provider () | Return the backend Provider. |
run (run_input, **options) | Run on the backend. |
set_options (**fields) | Set the options fields for the backend |
status () | Return the backend status. |
Attributes
options | Return the options for the backend |
version |
configuration
configuration()
Return the backend configuration.
Returns
the configuration for the backend.
Return type
name
name()
Return the backend name.
Returns
the name of the backend.
Return type
str
options
Return the options for the backend
The options of a backend are the dynamic parameters defining how the backend is used. These are used to control the run()
method.
properties
properties()
Return the backend properties.
Returns
the configuration for the backend. If the backend does not support properties, it returns None
.
Return type
provider
provider()
Return the backend Provider.
Returns
the Provider responsible for the backend.
Return type
run
abstract run(run_input, **options)
Run on the backend.
This method that will return a Job
object that run circuits. Depending on the backend this may be either an async or sync call. It is the discretion of the provider to decide whether running should block until the execution is finished or not. The Job class can handle either situation.
Parameters
- run_input (QuantumCircuit orSchedule or list) – An individual or a list of
QuantumCircuit
orSchedule
objects to run on the backend. For legacy providers migrating to the new versioned providers, provider interface aQasmQobj
orPulseQobj
objects should probably be supported too (but deprecated) for backwards compatibility. Be sure to update the docstrings of subclasses implementing this method to document that. New provider implementations should not do this though asqiskit.qobj
will be deprecated and removed along with the legacy providers interface. - options – Any kwarg options to pass to the backend for running the config. If a key is also present in the options attribute/object then the expectation is that the value specified will be used instead of what’s set in the options object.
Returns
The job object for the run
Return type
set_options
set_options(**fields)
Set the options fields for the backend
This method is used to update the options of a backend. If you need to change any of the options prior to running just pass in the kwarg with the new value for the options.
Parameters
fields – The fields to update the options
Raises
AttributeError – If the field passed in is not part of the options