Source code for qiskit_aer.utils.noise_model_inserter

# This code is part of Qiskit.
#
# (C) Copyright IBM 2019.
#
# 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
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.
"""
Noise model inserter module
The goal of this module is to add QuantumError gates (Kraus gates) to a circuit
based on a given noise model.
"""
import qiskit.compiler


[docs]def insert_noise(circuits, noise_model, transpile=False): """Return a noisy version of a QuantumCircuit. Args: circuits (QuantumCircuit or list[QuantumCircuit]): Input noise-free circuits. noise_model (NoiseModel): The noise model containing the errors to add transpile (Boolean): Should the circuit be transpiled into the noise model basis gates Returns: QuantumCircuit: The new circuit with the Kraus noise instructions inserted. Additional Information: The noisy circuit return by this function will consist of the original circuit with ``Kraus`` instructions inserted after all instructions referenced in the ``noise_model``. The resulting circuit cannot be ran on a quantum computer but can be executed on the :class:`~qiskit_aer.QasmSimulator`. """ is_circuits_list = isinstance(circuits, (list, tuple)) circuits = circuits if is_circuits_list else [circuits] result_circuits = [] local_errors = noise_model._local_quantum_errors default_errors = noise_model._default_quantum_errors for circuit in circuits: if transpile: transpiled_circuit = qiskit.compiler.transpile( circuit, basis_gates=noise_model.basis_gates ) else: transpiled_circuit = circuit qubit_indices = {bit: index for index, bit in enumerate(transpiled_circuit.qubits)} result_circuit = transpiled_circuit.copy(name=transpiled_circuit.name + "_with_noise") result_circuit.data = [] for inst, qargs, cargs in transpiled_circuit.data: result_circuit.data.append((inst, qargs, cargs)) qubits = tuple(qubit_indices[q] for q in qargs) # Priority for error model used: # local error > default error if inst.name in local_errors and qubits in local_errors[inst.name]: error = local_errors[inst.name][qubits] result_circuit.append(error.to_instruction(), qargs) elif inst.name in default_errors.keys(): error = default_errors[inst.name] result_circuit.append(error.to_instruction(), qargs) result_circuits.append(result_circuit) return result_circuits if is_circuits_list else result_circuits[0]