VirtualBackend

Options

From qrisp.interface is it possible to import the following kind of backends.

Option	Description
VirtualQiskitBackend	Allows to use a Qiskit Aer backend.
QiskitRuntimeBackend	Allows to use a Qiskit Runtime backend, exploiting the Qiskit’s Sampler primitive.

class VirtualBackend(run_func, port=None)

This class provides a virtual backend for circuit execution. Virtual means that the server is running on the same machine as a separate Python thread. This structure allows setting up convenient wrappers for foreign/ modified circuit dispatching code.

Circuits can be run using virtual_backend_instance.run(qc). The function that should be used to run a circuit can be specified during construction using the run_func parameter.

Parameters

run_funcfunction

A function that recieves a QuantumCircuit, an integer specifiying the amount of shots and a token in the form of a string. It returns the counts as a dictionary of bitstrings.

namestr, optional

A name for the virtual backend. The default is None.

portint, optional

The port on which to listen. The default is None.

Examples

We set up a VirtualBackend, which prints the received QuantumCircuit and returns the results of the QASM simulator.

def run_func(qasm_str, shots, token = ""):

    from qiskit import QuantumCircuit

    qiskit_qc = QuantumCircuit.from_qasm_str(qasm_str)

    print(qiskit_qc)

    from qiskit import Aer
    qiskit_backend = Aer.get_backend('qasm_simulator')

    #Run Circuit on the Qiskit backend
    return qiskit_backend.run(qiskit_qc, shots = shots).result().get_counts()

>>> from qrisp.interface import VirtualBackend
>>> example_backend = VirtualBackend(run_func)
>>> from qrisp import QuantumFloat
>>> qf = QuantumFloat(3)
>>> qf[:] = 4
>>> qf.get_measurement(backend = example_backend)
             ┌─┐
qf.0:   ─────┤M├──────
             └╥┘┌─┐
qf.1:   ──────╫─┤M├───
        ┌───┐ ║ └╥┘┌─┐
qf.2:   ┤ X ├─╫──╫─┤M├
        └───┘ ║  ║ └╥┘
cb_0: 1/══════╩══╬══╬═
              0  ║  ║
cb_1: 1/═════════╩══╬═
                 0  ║
cb_2: 1/════════════╩═
{4: 1.0}

Methods

VirtualBackend.__init__(run_func[, port])