ParityOS Qiskit

ParityOS extension adding an interface to Qiskit.

Installation

It is recommended to install this package in a separate Python virtual environment. For example:

# To create a standard Python virtual environment:
python -m venv my_new_venv && source my_new_venv/bin/activate
# Alternatively, to create a Anaconda/Miniconda environment:
conda create --name my_new_conda_env python=<version> && conda activate my_new_conda_env
# or a pyenv environment
pyenv virtualenv <version> my_new_venv && pyenv activate my_new_venv
# or a uv managed environment
uv venv -p <version>

where <version> is a python version and one of [3.11, 3.12, 3.13].

After activating the virtual environment, install via your favorite package manager, e.g.:

# using pip
pip install parityos-qiskit
# using uv
uv pip install parityos-qiskit

Exporter

parityos-qiskit offers an exporter of ParityOS to Qiskit quantum circuits.

from parityos.bits import get_q
from parityos.operators.circuit import Circuit
from parityos.operators.controlled_operator import CNOT
from parityos.operators.elementary_operator import H, Z
from parityos.operators.rotation_operator import RX
from parityos_qiskit.exporter import export_parityos_to_qiskit

# Create circuit qubits.
qubits = [get_q(name) for name in ("a", "b", "c")]

# Create the following circuit as sequence of gates, followed by a measurement of all qubits.
#     ┌───────┐┌───┐┌───┐   ┌─┐
# qa: ┤ Rx(2) ├┤ H ├┤ Z ├───┤M├
#     └───────┘├───┤└┬─┬┘   └╥┘
# qb: ─────────┤ X ├─┤M├─────╫─
#       ┌───┐  └─┬─┘ └╥┘ ┌─┐ ║
# qc: ──┤ H ├────■────╫──┤M├─╫─
#       └───┘         ║  └╥┘ ║
# c: 3/═══════════════╩═══╩══╩═
#                     1   2  0
circuit = Circuit(
    [
        RX(qubits[0], 2),
        H(qubits[0]),
        H(qubits[2]),
        CNOT(qubits[2], qubits[1]),
        Z(qubits[0]),
    ]
).measure_all()

# Export to Qiskit.
# Qiskit qubits are integer labeled. Passing `qubits` explicitly controls how ParityOS qubits are
# mapped to Qiskit qubits.
qiskit_result = export_parityos_to_qiskit(circuit, qubits=reversed(qubits))

print(qiskit_result.circuit.draw("text"))
#        ┌───┐               ┌─┐
# q_0: ──┤ H ├────■──────────┤M├───
#        └───┘  ┌─┴─┐     ┌─┐└╥┘
# q_1: ─────────┤ X ├─────┤M├─╫────
#      ┌───────┐├───┤┌───┐└╥┘ ║ ┌─┐
# q_2: ┤ Rx(2) ├┤ H ├┤ Z ├─╫──╫─┤M├
#      └───────┘└───┘└───┘ ║  ║ └╥┘
# c: 3/════════════════════╩══╩══╩═
#                          1  2  0

print(qiskit_result.qubit_map)  # Maps ParityOS qubits to Qiskit Qubit integer labels
# {Qubit(id='c'): 0, Qubit(id='b'): 1, Qubit(id='a'): 2}

print(qiskit_result.cbit_map)  # Maps ParityOS cbits to Qiskit Clbit integer labels
# {Cbit(id=0): 0, Cbit(id=1): 1, Cbit(id=2): 2}

License

This software package is made available under the 3-Clause BSD License. See License.txt for details.