VirtualBackend#

Options#

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

Option	Description
QiskitBackend	Allows to use a Qiskit Aer backend.
QiskitRuntimeBackend	Allows to use a Qiskit Runtime backend, exploiting the Qiskit’s Sampler primitive.
IQMBackend	Allows to use an IQM quantum computer as a backend via IQM Resonance.

class VirtualBackend(run_func, port=None)[source]#

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. It is required that the run_func specifies a default value for the shots parameter.

def run_func(qasm_str, shots = 1000, token = ""):

    from qiskit import QuantumCircuit

    qiskit_qc = QuantumCircuit.from_qasm_str(qasm_str)

    print(qiskit_qc)

    from qiskit_aer import AerSimulator
    qiskit_backend = AerSimulator()

    #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])