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---
title: PauliList (v0.31)
description: API reference for qiskit.quantum_info.PauliList in qiskit v0.31
in_page_toc_min_heading_level: 1
python_api_type: class
python_api_name: qiskit.quantum_info.PauliList
---
# PauliList
<Class id="qiskit.quantum_info.PauliList" isDedicatedPage={true} github="https://github.com/qiskit/qiskit/tree/stable/0.18/qiskit/quantum_info/operators/symplectic/pauli_list.py" signature="PauliList(data)" modifiers="class">
Bases: `qiskit.quantum_info.operators.symplectic.base_pauli.BasePauli`, `qiskit.quantum_info.operators.mixins.linear.LinearMixin`, `qiskit.quantum_info.operators.mixins.group.GroupMixin`
List of N-qubit Pauli operators.
This class is an efficient representation of a list of [`Pauli`](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli") operators. It supports 1D numpy array indexing returning a [`Pauli`](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli") for integer indexes or a [`PauliList`](#qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList") for slice or list indices.
**Initialization**
A PauliList object can be initialized in several ways.
> **`PauliList(list[str])`**
>
> where strings are same representation with [`Pauli`](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli").
>
> **`PauliList(Pauli) and PauliList(list[Pauli])`**
>
> where Pauli is [`Pauli`](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli").
>
> **`PauliList.from_symplectic(z, x, phase)`**
>
> where `z` and `x` are 2 dimensional boolean `numpy.ndarrays` and `phase` is an integer in `[0, 1, 2, 3]`.
For example,
```python
import numpy as np
from qiskit.quantum_info import Pauli, PauliList
# 1. init from list[str]
pauli_list = PauliList(["II", "+ZI", "-iYY"])
print("1. ", pauli_list)
pauli1 = Pauli("iXI")
pauli2 = Pauli("iZZ")
# 2. init from Pauli
print("2. ", PauliList(pauli1))
# 3. init from list[Pauli]
print("3. ", PauliList([pauli1, pauli2]))
# 4. init from np.ndarray
z = np.array([[True, True], [False, False]])
x = np.array([[False, True], [True, False]])
phase = np.array([0, 1])
pauli_list = PauliList.from_symplectic(z, x)
print("4. ", pauli_list)
```
```
1. ['II', 'ZI', '-iYY']
2. ['iXI']
3. ['iXI', 'iZZ']
4. ['YZ', 'IX']
```
**Data Access**
The individual Paulis can be accessed and updated using the `[]` operator which accepts integer, lists, or slices for selecting subsets of PauliList. If integer is given, it returns Pauli not PauliList.
```python
pauli_list = PauliList(["XX", "ZZ", "IZ"])
print("Integer: ", repr(pauli_list[1]))
print("List: ", repr(pauli_list[[0, 2]]))
print("Slice: ", repr(pauli_list[0:2]))
```
```
Integer: Pauli('ZZ')
List: PauliList(['XX', 'IZ'])
Slice: PauliList(['XX', 'ZZ'])
```
**Iteration**
Rows in the Pauli table can be iterated over like a list. Iteration can also be done using the label or matrix representation of each row using the [`label_iter()`](qiskit.quantum_info.PauliList#label_iter "qiskit.quantum_info.PauliList.label_iter") and [`matrix_iter()`](qiskit.quantum_info.PauliList#matrix_iter "qiskit.quantum_info.PauliList.matrix_iter") methods.
Initialize the PauliList.
**Parameters**
**data** ([*Pauli*](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli") *or list*) input data for Paulis. If input is a list each item in the list must be a Pauli object or Pauli str.
**Raises**
**QiskitError** if input array is invalid shape.
**Additional Information:**
The input array is not copied so multiple Pauli tables can share the same underlying array.
## Methods
<span id="qiskit-quantum-info-paulilist-adjoint" />
### adjoint
<Function id="qiskit.quantum_info.PauliList.adjoint" signature="PauliList.adjoint()">
Return the adjoint of each Pauli in the list.
</Function>
<span id="qiskit-quantum-info-paulilist-anticommutes" />
### anticommutes
<Function id="qiskit.quantum_info.PauliList.anticommutes" signature="PauliList.anticommutes(other, qargs=None)">
Return True if other Pauli that anticommutes with other.
**Parameters**
* **other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) another PauliList operator.
* **qargs** (*list*) qubits to apply dot product on (default: None).
**Returns**
True if Paulis anticommute, False if they commute.
**Return type**
bool
</Function>
<span id="qiskit-quantum-info-paulilist-anticommutes-with-all" />
### anticommutes\_with\_all
<Function id="qiskit.quantum_info.PauliList.anticommutes_with_all" signature="PauliList.anticommutes_with_all(other)">
Return indexes of rows that commute other.
If other is a multi-row Pauli list the returned vector indexes rows of the current PauliList that anti-commute with *all* Paulis in other. If no rows satisfy the condition the returned array will be empty.
**Parameters**
**other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) a single Pauli or multi-row PauliList.
**Returns**
index array of the anti-commuting rows.
**Return type**
array
</Function>
<span id="qiskit-quantum-info-paulilist-argsort" />
### argsort
<Function id="qiskit.quantum_info.PauliList.argsort" signature="PauliList.argsort(weight=False, phase=False)">
Return indices for sorting the rows of the table.
The default sort method is lexicographic sorting by qubit number. By using the weight kwarg the output can additionally be sorted by the number of non-identity terms in the Pauli, where the set of all Paulis of a given weight are still ordered lexicographically.
**Parameters**
* **weight** (*bool*) Optionally sort by weight if True (Default: False).
* **phase** (*bool*) Optionally sort by phase before weight or order (Default: False).
**Returns**
the indices for sorting the table.
**Return type**
array
</Function>
<span id="qiskit-quantum-info-paulilist-commutes" />
### commutes
<Function id="qiskit.quantum_info.PauliList.commutes" signature="PauliList.commutes(other, qargs=None)">
Return True for each Pauli that commutes with other.
**Parameters**
* **other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) another PauliList operator.
* **qargs** (*list*) qubits to apply dot product on (default: None).
**Returns**
True if Paulis commute, False if they anti-commute.
**Return type**
bool
</Function>
<span id="qiskit-quantum-info-paulilist-commutes-with-all" />
### commutes\_with\_all
<Function id="qiskit.quantum_info.PauliList.commutes_with_all" signature="PauliList.commutes_with_all(other)">
Return indexes of rows that commute other.
If other is a multi-row Pauli list the returned vector indexes rows of the current PauliList that commute with *all* Paulis in other. If no rows satisfy the condition the returned array will be empty.
**Parameters**
**other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) a single Pauli or multi-row PauliList.
**Returns**
index array of the commuting rows.
**Return type**
array
</Function>
<span id="qiskit-quantum-info-paulilist-compose" />
### compose
<Function id="qiskit.quantum_info.PauliList.compose" signature="PauliList.compose(other, qargs=None, front=False, inplace=False)">
Return the composition self∘other for each Pauli in the list.
**Parameters**
* **other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) another PauliList.
* **qargs** (*None or list*) qubits to apply dot product on (Default: None).
* **front** (*bool*) If True use dot composition method \[default: False].
* **inplace** (*bool*) If True update in-place (default: False).
**Returns**
the list of composed Paulis.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
**Raises**
**QiskitError** if other cannot be converted to a PauliList, does not have either 1 or the same number of Paulis as the current list, or has the wrong number of qubits for the specified qargs.
</Function>
<span id="qiskit-quantum-info-paulilist-conjugate" />
### conjugate
<Function id="qiskit.quantum_info.PauliList.conjugate" signature="PauliList.conjugate()">
Return the conjugate of each Pauli in the list.
</Function>
<span id="qiskit-quantum-info-paulilist-copy" />
### copy
<Function id="qiskit.quantum_info.PauliList.copy" signature="PauliList.copy()">
Make a deep copy of current operator.
</Function>
<span id="qiskit-quantum-info-paulilist-delete" />
### delete
<Function id="qiskit.quantum_info.PauliList.delete" signature="PauliList.delete(ind, qubit=False)">
Return a copy with Pauli rows deleted from table.
When deleting qubits the qubit index is the same as the column index of the underlying `X` and `Z` arrays.
**Parameters**
* **ind** (*int or list*) index(es) to delete.
* **qubit** (*bool*) if True delete qubit columns, otherwise delete Pauli rows (Default: False).
**Returns**
the resulting table with the entries removed.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
**Raises**
**QiskitError** if ind is out of bounds for the array size or number of qubits.
</Function>
<span id="qiskit-quantum-info-paulilist-dot" />
### dot
<Function id="qiskit.quantum_info.PauliList.dot" signature="PauliList.dot(other, qargs=None, inplace=False)">
Return the composition other∘self for each Pauli in the list.
**Parameters**
* **other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) another PauliList.
* **qargs** (*None or list*) qubits to apply dot product on (Default: None).
* **inplace** (*bool*) If True update in-place (default: False).
**Returns**
the list of composed Paulis.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
**Raises**
**QiskitError** if other cannot be converted to a PauliList, does not have either 1 or the same number of Paulis as the current list, or has the wrong number of qubits for the specified qargs.
</Function>
<span id="qiskit-quantum-info-paulilist-equiv" />
### equiv
<Function id="qiskit.quantum_info.PauliList.equiv" signature="PauliList.equiv(other)">
Entrywise comparison of Pauli equivalence up to global phase.
**Parameters**
**other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList") *or*[*Pauli*](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli")) a comparison object.
**Returns**
**An array of True or False for entrywise equivalence**
of the current table.
**Return type**
np.ndarray
</Function>
<span id="qiskit-quantum-info-paulilist-evolve" />
### evolve
<Function id="qiskit.quantum_info.PauliList.evolve" signature="PauliList.evolve(other, qargs=None)">
Evolve the Pauli by a Clifford.
This returns the Pauli $P^\prime = C.P.C^\dagger$.
**Parameters**
* **other** ([*Pauli*](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli") *or*[*Clifford*](qiskit.quantum_info.Clifford "qiskit.quantum_info.Clifford") *or*[*QuantumCircuit*](qiskit.circuit.QuantumCircuit "qiskit.circuit.QuantumCircuit")) The Clifford operator to evolve by.
* **qargs** (*list*) a list of qubits to apply the Clifford to.
**Returns**
the Pauli $C.P.C^\dagger$.
**Return type**
[Pauli](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli")
**Raises**
**QiskitError** if the Clifford number of qubits and qargs dont match.
</Function>
<span id="qiskit-quantum-info-paulilist-expand" />
### expand
<Function id="qiskit.quantum_info.PauliList.expand" signature="PauliList.expand(other)">
Return the expand product of each Pauli in the list.
**Parameters**
**other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) another PauliList.
**Returns**
the list of tensor product Paulis.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
**Raises**
**QiskitError** if other cannot be converted to a PauliList, does not have either 1 or the same number of Paulis as the current list.
</Function>
<span id="qiskit-quantum-info-paulilist-from-symplectic" />
### from\_symplectic
<Function id="qiskit.quantum_info.PauliList.from_symplectic" signature="PauliList.from_symplectic(z, x, phase=0)" modifiers="classmethod">
Construct a PauliList from a symplectic data.
**Parameters**
* **z** (*np.ndarray*) 2D boolean Numpy array.
* **x** (*np.ndarray*) 2D boolean Numpy array.
* **phase** (*np.ndarray or None*) Optional, 1D integer array from Z\_4.
**Returns**
the constructed PauliList.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
</Function>
<span id="qiskit-quantum-info-paulilist-input-dims" />
### input\_dims
<Function id="qiskit.quantum_info.PauliList.input_dims" signature="PauliList.input_dims(qargs=None)">
Return tuple of input dimension for specified subsystems.
</Function>
<span id="qiskit-quantum-info-paulilist-insert" />
### insert
<Function id="qiskit.quantum_info.PauliList.insert" signature="PauliList.insert(ind, value, qubit=False)">
Insert Paulis into the table.
When inserting qubits the qubit index is the same as the column index of the underlying `X` and `Z` arrays.
**Parameters**
* **ind** (*int*) index to insert at.
* **value** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) values to insert.
* **qubit** (*bool*) if True delete qubit columns, otherwise delete Pauli rows (Default: False).
**Returns**
the resulting table with the entries inserted.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
**Raises**
**QiskitError** if the insertion index is invalid.
</Function>
<span id="qiskit-quantum-info-paulilist-inverse" />
### inverse
<Function id="qiskit.quantum_info.PauliList.inverse" signature="PauliList.inverse()">
Return the inverse of each Pauli in the list.
</Function>
<span id="qiskit-quantum-info-paulilist-label-iter" />
### label\_iter
<Function id="qiskit.quantum_info.PauliList.label_iter" signature="PauliList.label_iter()">
Return a label representation iterator.
This is a lazy iterator that converts each row into the string label only as it is used. To convert the entire table to labels use the [`to_labels()`](qiskit.quantum_info.PauliList#to_labels "qiskit.quantum_info.PauliList.to_labels") method.
**Returns**
label iterator object for the PauliList.
**Return type**
LabelIterator
</Function>
<span id="qiskit-quantum-info-paulilist-matrix-iter" />
### matrix\_iter
<Function id="qiskit.quantum_info.PauliList.matrix_iter" signature="PauliList.matrix_iter(sparse=False)">
Return a matrix representation iterator.
This is a lazy iterator that converts each row into the Pauli matrix representation only as it is used. To convert the entire table to matrices use the [`to_matrix()`](qiskit.quantum_info.PauliList#to_matrix "qiskit.quantum_info.PauliList.to_matrix") method.
**Parameters**
**sparse** (*bool*) optionally return sparse CSR matrices if True, otherwise return Numpy array matrices (Default: False)
**Returns**
matrix iterator object for the PauliList.
**Return type**
MatrixIterator
</Function>
<span id="qiskit-quantum-info-paulilist-output-dims" />
### output\_dims
<Function id="qiskit.quantum_info.PauliList.output_dims" signature="PauliList.output_dims(qargs=None)">
Return tuple of output dimension for specified subsystems.
</Function>
<span id="qiskit-quantum-info-paulilist-power" />
### power
<Function id="qiskit.quantum_info.PauliList.power" signature="PauliList.power(n)">
Return the compose of a operator with itself n times.
**Parameters**
**n** (*int*) the number of times to compose with self (n>0).
**Returns**
the n-times composed operator.
**Return type**
[Pauli](qiskit.quantum_info.Pauli "qiskit.quantum_info.Pauli")
**Raises**
**QiskitError** if the input and output dimensions of the operator are not equal, or the power is not a positive integer.
</Function>
<span id="qiskit-quantum-info-paulilist-reshape" />
### reshape
<Function id="qiskit.quantum_info.PauliList.reshape" signature="PauliList.reshape(input_dims=None, output_dims=None, num_qubits=None)">
Return a shallow copy with reshaped input and output subsystem dimensions.
**Parameters**
* **input\_dims** (*None or tuple*) new subsystem input dimensions. If None the original input dims will be preserved \[Default: None].
* **output\_dims** (*None or tuple*) new subsystem output dimensions. If None the original output dims will be preserved \[Default: None].
* **num\_qubits** (*None or int*) reshape to an N-qubit operator \[Default: None].
**Returns**
returns self with reshaped input and output dimensions.
**Return type**
BaseOperator
**Raises**
**QiskitError** if combined size of all subsystem input dimension or subsystem output dimensions is not constant.
</Function>
<span id="qiskit-quantum-info-paulilist-sort" />
### sort
<Function id="qiskit.quantum_info.PauliList.sort" signature="PauliList.sort(weight=False, phase=False)">
Sort the rows of the table.
The default sort method is lexicographic sorting by qubit number. By using the weight kwarg the output can additionally be sorted by the number of non-identity terms in the Pauli, where the set of all Paulis of a given weight are still ordered lexicographically.
**Example**
Consider sorting all a random ordering of all 2-qubit Paulis
```python
from numpy.random import shuffle
from qiskit.quantum_info.operators import PauliList
# 2-qubit labels
labels = ['II', 'IX', 'IY', 'IZ', 'XI', 'XX', 'XY', 'XZ',
'YI', 'YX', 'YY', 'YZ', 'ZI', 'ZX', 'ZY', 'ZZ']
# Shuffle Labels
shuffle(labels)
pt = PauliList(labels)
print('Initial Ordering')
print(pt)
# Lexicographic Ordering
srt = pt.sort()
print('Lexicographically sorted')
print(srt)
# Weight Ordering
srt = pt.sort(weight=True)
print('Weight sorted')
print(srt)
```
```
Initial Ordering
['XI', 'XY', 'IZ', 'ZI', 'ZX', 'IY', 'YY', 'IX', 'ZY', 'XZ', 'ZZ', 'II',
'YX', 'XX', 'YI', 'YZ']
Lexicographically sorted
['II', 'IX', 'IY', 'IZ', 'XI', 'XX', 'XY', 'XZ', 'YI', 'YX', 'YY', 'YZ',
'ZI', 'ZX', 'ZY', 'ZZ']
Weight sorted
['II', 'IX', 'IY', 'IZ', 'XI', 'YI', 'ZI', 'XX', 'XY', 'XZ', 'YX', 'YY',
'YZ', 'ZX', 'ZY', 'ZZ']
```
**Parameters**
* **weight** (*bool*) optionally sort by weight if True (Default: False).
* **phase** (*bool*) Optionally sort by phase before weight or order (Default: False).
**Returns**
a sorted copy of the original table.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
</Function>
<span id="qiskit-quantum-info-paulilist-tensor" />
### tensor
<Function id="qiskit.quantum_info.PauliList.tensor" signature="PauliList.tensor(other)">
Return the tensor product with each Pauli in the list.
**Parameters**
**other** ([*PauliList*](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")) another PauliList.
**Returns**
the list of tensor product Paulis.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
**Raises**
**QiskitError** if other cannot be converted to a PauliList, does not have either 1 or the same number of Paulis as the current list.
</Function>
<span id="qiskit-quantum-info-paulilist-to-labels" />
### to\_labels
<Function id="qiskit.quantum_info.PauliList.to_labels" signature="PauliList.to_labels(array=False)">
Convert a PauliList to a list Pauli string labels.
For large PauliLists converting using the `array=True` kwarg will be more efficient since it allocates memory for the full Numpy array of labels in advance.
| Label | Symplectic | Matrix |
| ----- | ---------- | ----------------------------------------------- |
| `"I"` | $[0, 0]$ | $\begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix}$ |
| `"X"` | $[1, 0]$ | $\begin{bmatrix} 0 & 1 \\ 1 & 0 \end{bmatrix}$ |
| `"Y"` | $[1, 1]$ | $\begin{bmatrix} 0 & -i \\ i & 0 \end{bmatrix}$ |
| `"Z"` | $[0, 1]$ | $\begin{bmatrix} 1 & 0 \\ 0 & -1 \end{bmatrix}$ |
**Parameters**
**array** (*bool*) return a Numpy array if True, otherwise return a list (Default: False).
**Returns**
The rows of the PauliList in label form.
**Return type**
list or array
</Function>
<span id="qiskit-quantum-info-paulilist-to-matrix" />
### to\_matrix
<Function id="qiskit.quantum_info.PauliList.to_matrix" signature="PauliList.to_matrix(sparse=False, array=False)">
Convert to a list or array of Pauli matrices.
For large PauliLists converting using the `array=True` kwarg will be more efficient since it allocates memory a full rank-3 Numpy array of matrices in advance.
| Label | Symplectic | Matrix |
| ----- | ---------- | ----------------------------------------------- |
| `"I"` | $[0, 0]$ | $\begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix}$ |
| `"X"` | $[1, 0]$ | $\begin{bmatrix} 0 & 1 \\ 1 & 0 \end{bmatrix}$ |
| `"Y"` | $[1, 1]$ | $\begin{bmatrix} 0 & -i \\ i & 0 \end{bmatrix}$ |
| `"Z"` | $[0, 1]$ | $\begin{bmatrix} 1 & 0 \\ 0 & -1 \end{bmatrix}$ |
**Parameters**
* **sparse** (*bool*) if True return sparse CSR matrices, otherwise return dense Numpy arrays (Default: False).
* **array** (*bool*) return as rank-3 numpy array if True, otherwise return a list of Numpy arrays (Default: False).
**Returns**
A list of dense Pauli matrices if array=False and sparse=False. list: A list of sparse Pauli matrices if array=False and sparse=True. array: A dense rank-3 array of Pauli matrices if array=True.
**Return type**
list
</Function>
<span id="qiskit-quantum-info-paulilist-transpose" />
### transpose
<Function id="qiskit.quantum_info.PauliList.transpose" signature="PauliList.transpose()">
Return the transpose of each Pauli in the list.
</Function>
<span id="qiskit-quantum-info-paulilist-unique" />
### unique
<Function id="qiskit.quantum_info.PauliList.unique" signature="PauliList.unique(return_index=False, return_counts=False)">
Return unique Paulis from the table.
**Example**
```python
from qiskit.quantum_info.operators import PauliList
pt = PauliList(['X', 'Y', '-X', 'I', 'I', 'Z', 'X', 'iZ'])
unique = pt.unique()
print(unique)
```
```
['X', 'Y', '-X', 'I', 'Z', 'iZ']
```
**Parameters**
* **return\_index** (*bool*) If True, also return the indices that result in the unique array. (Default: False)
* **return\_counts** (*bool*) If True, also return the number of times each unique item appears in the table.
**Returns**
**unique**
the table of the unique rows.
**unique\_indices: np.ndarray, optional**
The indices of the first occurrences of the unique values in the original array. Only provided if `return_index` is True.
**unique\_counts: np.array, optional**
The number of times each of the unique values comes up in the original array. Only provided if `return_counts` is True.
**Return type**
[PauliList](qiskit.quantum_info.PauliList "qiskit.quantum_info.PauliList")
</Function>
## Attributes
### dim
<Attribute id="qiskit.quantum_info.PauliList.dim">
Return tuple (input\_shape, output\_shape).
</Attribute>
### num\_qubits
<Attribute id="qiskit.quantum_info.PauliList.num_qubits">
Return the number of qubits if a N-qubit operator or None otherwise.
</Attribute>
### phase
<Attribute id="qiskit.quantum_info.PauliList.phase">
Return the phase exponent of the PauliList.
</Attribute>
### qargs
<Attribute id="qiskit.quantum_info.PauliList.qargs">
Return the qargs for the operator.
</Attribute>
### settings
<Attribute id="qiskit.quantum_info.PauliList.settings">
Return operator settings.
</Attribute>
### shape
<Attribute id="qiskit.quantum_info.PauliList.shape">
The full shape of the `array()`
</Attribute>
### size
<Attribute id="qiskit.quantum_info.PauliList.size">
The number of Pauli rows in the table.
</Attribute>
### x
<Attribute id="qiskit.quantum_info.PauliList.x">
The x array for the symplectic representation.
</Attribute>
### z
<Attribute id="qiskit.quantum_info.PauliList.z">
The z array for the symplectic representation.
</Attribute>
</Class>