Source code for qiskit.quantum_info.operators.symplectic.pauli_utils

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# (C) Copyright IBM 2017, 2020
# This code is licensed under the Apache License, Version 2.0. You may
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PauliList utility functions.

from __future__ import annotations

from qiskit.quantum_info.operators.symplectic.pauli_list import PauliList

[docs]def pauli_basis(num_qubits: int, weight: bool = False) -> PauliList: """Return the ordered PauliList for the n-qubit Pauli basis. Args: num_qubits (int): number of qubits weight (bool): if True optionally return the basis sorted by Pauli weight rather than lexicographic order (Default: False) Returns: PauliList: the Paulis for the basis """ pauli_1q = PauliList(["I", "X", "Y", "Z"]) if num_qubits == 1: return pauli_1q pauli = pauli_1q for _ in range(num_qubits - 1): pauli = pauli_1q.tensor(pauli) if weight: return pauli.sort(weight=True) return pauli