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---
title: PauliLindbladError (latest version)
description: API reference for qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError in the latest version of qiskit-ibm-runtime
in_page_toc_min_heading_level: 1
python_api_type: class
python_api_name: qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError
---
# PauliLindbladError
<Class id="qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError" isDedicatedPage={true} github="https://github.com/Qiskit/qiskit-ibm-runtime/tree/stable/0.33/qiskit_ibm_runtime/utils/noise_learner_result.py#L42-L133" signature="PauliLindbladError(generators, rates)" modifiers="class">
A Pauli error channel generated by a Pauli Lindblad dissipators.
This operator represents an N-qubit quantum error channel $E(\rho) = e^{\sum_j r_j D_{P_j}}(\rho)$ generated by Pauli Lindblad dissipators $D_P(\rho) = P \rho P - \rho$, where $P_j$ are N-qubit `Pauli` operators.
The list of Pauli generator terms are stored as a `PauliList` and can be accessed via the [`generators`](#qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.generators "qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.generators") attribute. The array of dissipator rates $r_j$ can be accessed via the [`rates`](#qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.rates "qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.rates") attribute.
The equivalent Pauli error channel can be constructed as a composition of single-Pauli channel terms
$$
E = e^{\sum_j r_j D_{P_j}} = \prod_j e^{r_j D_{P_j}}
= prod_j \left( (1 - p_j) S_I + p_j S_{P_j} \right)
$$
where $p_j = \frac12 - \frac12 e^{-2 r_j}$ \[1].
**Parameters**
* **generators** ([`PauliList`](/api/qiskit/qiskit.quantum_info.PauliList "(in Qiskit v1.2)")) A list of the Pauli Lindblad generators for the error channel.
* **rates** (`Sequence`\[`float`]) A list of the rates for the Pauli-Lindblad `generators`.
**Raises**
**ValueError** If `generators` and `rates` have different lengths.
**References**
1. E. van den Berg, Z. Minev, A. Kandala, K. Temme, *Probabilistic error cancellation with sparse PauliLindblad models on noisy quantum processors*, Nature Physics volume 19, pages11161121 (2023). [arXiv:2201.09866 \[quant-ph\]](https://arxiv.org/abs/2201.09866)
## Attributes
### generators
<Attribute id="qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.generators">
The Pauli Lindblad generators of this [`PauliLindbladError`](#qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError "qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError").
**Return type**
[`PauliList`](/api/qiskit/qiskit.quantum_info.PauliList "(in Qiskit v1.2)")
</Attribute>
### num\_qubits
<Attribute id="qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.num_qubits">
The number of qubits in this [`PauliLindbladError`](#qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError "qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError").
**Return type**
`int`
</Attribute>
### rates
<Attribute id="qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.rates">
The Lindblad generator rates of this quantum error.
**Return type**
[`ndarray`](https://numpy.org/doc/stable/reference/generated/numpy.ndarray.html#numpy.ndarray "(in NumPy v2.1)")\[`Any`, [`dtype`](https://numpy.org/doc/stable/reference/generated/numpy.dtype.html#numpy.dtype "(in NumPy v2.1)")\[`float64`]]
</Attribute>
## Methods
### restrict\_num\_bodies
<Function id="qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError.restrict_num_bodies" github="https://github.com/Qiskit/qiskit-ibm-runtime/tree/stable/0.33/qiskit_ibm_runtime/utils/noise_learner_result.py#L109-L126" signature="restrict_num_bodies(num_qubits)">
The [`PauliLindbladError`](#qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError "qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError") containing only those terms acting on exactly `num_qubits` qubits.
**Parameters**
**num\_qubits** (`int`) The number of qubits that the returned error acts on.
**Return type**
[`PauliLindbladError`](#qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError "qiskit_ibm_runtime.utils.noise_learner_result.PauliLindbladError")
**Returns**
The error containing only those terms acting on exactly `num_qubits` qubits.
**Raises**
**ValueError** If `num_qubits` is smaller than `0`.
</Function>
</Class>