Rename BasicAer to BasicProvider and refactor interface to follow BackendV2

docs/apidoc/index.rst

@@ -18,8 +18,8 @@ API Reference
    assembler
    dagcircuit
    passmanager
-   providers_basicaer
    providers
+   providers_basic_provider
    providers_fake_provider
    providers_models
    pulse

docs/apidoc/providers_basic_provider.rst

@@ -0,0 +1,6 @@
+.. _qiskit-providers-basicprovider:
+
+.. automodule:: qiskit.providers.basic_provider
+   :no-members:
+   :no-inherited-members:
+   :no-special-members:

examples/python/ghz.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -14,8 +14,8 @@
 GHZ state example. It also compares running on experiment and simulator.
 """
 
-from qiskit import QuantumCircuit
-from qiskit import BasicAer, transpile
+from qiskit import QuantumCircuit, transpile
+from qiskit.providers.basic_provider import BasicSimulator
 
 
 ###############################################################
@@ -34,8 +34,8 @@
 for i in range(num_qubits):
     qc.measure(i, i)
 
-sim_backend = BasicAer.get_backend("qasm_simulator")
+sim_backend = BasicSimulator()
 job = sim_backend.run(transpile(qc, sim_backend), shots=1024)
 result = job.result()
-print("Qasm simulator : ")
+print("Basic simulator : ")
 print(result.get_counts(qc))

examples/python/initialize.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -15,7 +15,8 @@
 """
 
 import math
-from qiskit import QuantumCircuit, transpile, BasicAer
+from qiskit import QuantumCircuit, transpile
+from qiskit.providers.basic_provider import BasicSimulator
 
 
 ###############################################################
@@ -58,7 +59,7 @@
 print([format(abs(x * x), ".3f") for x in desired_vector])
 
 # Initialize on local simulator
-sim_backend = BasicAer.get_backend("qasm_simulator")
+sim_backend = BasicSimulator()
 job = sim_backend.run(transpile(circuit, sim_backend), shots=shots)
 result = job.result()
 

examples/python/load_qasm.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017, 2018.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -13,14 +13,13 @@
 """Example on how to load a file into a QuantumCircuit."""
 
 from qiskit import QuantumCircuit
-from qiskit import BasicAer
+from qiskit.providers.basic_provider import BasicSimulator
 
 circ = QuantumCircuit.from_qasm_file("examples/qasm/entangled_registers.qasm")
 print(circ)
 
 # See the backend
-sim_backend = BasicAer.get_backend("qasm_simulator")
-
+sim_backend = BasicSimulator()
 
 # Compile and run the Quantum circuit on a local simulator backend
 job_sim = sim_backend.run(circ)

examples/python/qft.py

@@ -16,7 +16,8 @@
 
 import math
 from qiskit import QuantumCircuit
-from qiskit import transpile, BasicAer
+from qiskit import transpile
+from qiskit.providers.basic_provider import BasicSimulator
 
 
 ###############################################################
@@ -66,8 +67,8 @@ def qft(circ, n):
 print(qft4)
 print(qft5)
 
-print("Qasm simulator")
-sim_backend = BasicAer.get_backend("qasm_simulator")
+print("Basic simulator")
+sim_backend = BasicSimulator()
 job = sim_backend.run(transpile([qft3, qft4, qft5], sim_backend), shots=1024)
 result = job.result()
 print(result.get_counts(qft3))

examples/python/rippleadd.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -16,13 +16,13 @@
 """
 
 from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit
-from qiskit import BasicAer
 from qiskit import transpile
+from qiskit.providers.basic_provider import BasicSimulator
 
 ###############################################################
 # Set the backend name and coupling map.
 ###############################################################
-backend = BasicAer.get_backend("qasm_simulator")
+backend = BasicSimulator()
 coupling_map = [
     [0, 1],
     [0, 8],

examples/python/teleport.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -18,14 +18,14 @@
 """
 
 from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit
-from qiskit import BasicAer
 from qiskit import transpile
+from qiskit.providers.basic_provider import BasicSimulator
 
 ###############################################################
 # Set the backend name and coupling map.
 ###############################################################
 coupling_map = [[0, 1], [0, 2], [1, 2], [3, 2], [3, 4], [4, 2]]
-backend = BasicAer.get_backend("qasm_simulator")
+backend = BasicSimulator()
 
 ###############################################################
 # Make a quantum program for quantum teleportation.

examples/python/using_qiskit_terra_level_0.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017, 2018.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -14,16 +14,13 @@
 Example showing how to use Qiskit at introduction level.
 
 This example shows the most basic way to use Qiskit. It builds some circuits
-and runs them on both the BasicAer (local Qiskit provider) or IBM Quantum (remote IBM Quantum provider).
-
-To control the compile parameters we have provided a transpile function which can be used
-as a level 1 user.
-
+and runs them on the BasicProvider (local Qiskit provider).
 """
 
 # Import the Qiskit modules
 from qiskit import QuantumCircuit
-from qiskit import transpile, BasicAer
+from qiskit import transpile
+from qiskit.providers.basic_provider import BasicSimulator
 
 # making first circuit: bell state
 qc1 = QuantumCircuit(2, 2)
@@ -36,12 +33,8 @@
 qc2.h([0, 1])
 qc2.measure([0, 1], [0, 1])
 
-# setting up the backend
-print("(BasicAER Backends)")
-print(BasicAer.backends())
-
 # running the job
-sim_backend = BasicAer.get_backend("qasm_simulator")
+sim_backend = BasicSimulator()
 job_sim = sim_backend.run(transpile([qc1, qc2], sim_backend))
 sim_result = job_sim.result()
 

qiskit/__init__.py

@@ -59,9 +59,6 @@
 import qiskit.circuit.measure
 import qiskit.circuit.reset
 
-# Please note these are global instances, not modules.
-from qiskit.providers.basicaer import BasicAer
-
 _config = _user_config.get_config()
 
 from qiskit.compiler import transpile, assemble, schedule, sequence
@@ -70,7 +67,6 @@
 
 __all__ = [
     "AncillaRegister",
-    "BasicAer",
     "ClassicalRegister",
     "MissingOptionalLibraryError",
     "QiskitError",

qiskit/circuit/__init__.py

@@ -71,8 +71,7 @@
 .. plot::
    :include-source:
 
-   from qiskit import BasicAer, transpile, QuantumRegister, ClassicalRegister, QuantumCircuit
-
+   from qiskit import transpile, QuantumRegister, ClassicalRegister, QuantumCircuit
    qr = QuantumRegister(1)
    cr = ClassicalRegister(1)
    qc = QuantumCircuit(qr, cr)
@@ -82,7 +81,8 @@
 
 .. code-block::
 
-   backend = BasicAer.get_backend('qasm_simulator')
+   from qiskit.providers.basic_provider import BasicSimulator
+   backend = BasicSimulator()
    tqc = transpile(qc, backend)
    counts = backend.run(tqc).result().get_counts()
 
@@ -100,7 +100,7 @@
 .. plot::
    :include-source:
 
-   from qiskit import BasicAer, transpile, QuantumRegister, ClassicalRegister, QuantumCircuit
+   from qiskit import transpile, QuantumRegister, ClassicalRegister, QuantumCircuit
 
    qr = QuantumRegister(1)
    cr = ClassicalRegister(1)
@@ -115,7 +115,8 @@
 
 .. code-block::
 
-   backend = BasicAer.get_backend('qasm_simulator')
+   from qiskit.providers.basic_provider import BasicSimulator
+   backend = BasicSimulator()
    tqc = transpile(qc, backend)
    counts = backend.run(tqc).result().get_counts()
 

qiskit/providers/basicaer/__init__.py → qiskit/providers/basic_provider/__init__.py

@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017, 2018.
+# (C) Copyright IBM 2017, 2023.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -11,20 +11,20 @@
 # that they have been altered from the originals.
 
 """
-====================================================================
-BasicAer: Python-based Simulators (:mod:`qiskit.providers.basicaer`)
-====================================================================
+================================================================================
+BasicProvider: Python-based Simulators (:mod:`qiskit.providers.basic_provider`)
+================================================================================
 
-.. currentmodule:: qiskit.providers.basicaer
+.. currentmodule:: qiskit.providers.basic_provider
 
-A module of Python-based quantum simulators.  Simulators are accessed
-via the `BasicAer` provider, e.g.:
+A module of Python-based quantum simulators. Simulators can be accessed
+via the `BasicProvider` provider, e.g.:
 
 .. code-block::
 
-   from qiskit import BasicAer
+   from qiskit.providers.basic_provider import BasicProvider
 
-   backend = BasicAer.get_backend('qasm_simulator')
+   backend = BasicProvider().get_backend('basic_simulator')
 
 
 Simulators
@@ -33,41 +33,34 @@
 .. autosummary::
    :toctree: ../stubs/
 
-   QasmSimulatorPy
-   StatevectorSimulatorPy
-   UnitarySimulatorPy
+   BasicSimulator
 
 Provider
 ========
 
 .. autosummary::
    :toctree: ../stubs/
 
-   BasicAerProvider
+   BasicProvider
 
 Job Class
 =========
 
 .. autosummary::
    :toctree: ../stubs/
 
-   BasicAerJob
+   BasicProviderJob
 
 Exceptions
 ==========
 
 .. autosummary::
    :toctree: ../stubs/
 
-   BasicAerError
+   BasicProviderError
 """
 
-from .basicaerprovider import BasicAerProvider
-from .basicaerjob import BasicAerJob
-from .qasm_simulator import QasmSimulatorPy
-from .statevector_simulator import StatevectorSimulatorPy
-from .unitary_simulator import UnitarySimulatorPy
-from .exceptions import BasicAerError
-
-# Global instance to be used as the entry point for convenience.
-BasicAer = BasicAerProvider()
+from .basic_provider import BasicProvider
+from .basic_provider_job import BasicProviderJob
+from .basic_simulator import BasicSimulator
+from .exceptions import BasicProviderError