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Editing: _disjoint_set.cpython-311.pyc
� d�ck � �$ � d Z G d� d� � ZdS )z Disjoint set data structure c �P � e Zd ZdZd d�Zd� Zd� Zd� Zd� Zd� Z d � Z d � Z d � Z d � Z dS )� DisjointSeta Disjoint set data structure for incremental connectivity queries. .. versionadded:: 1.6.0 Attributes ---------- n_subsets : int The number of subsets. Methods ------- add merge connected subset subsets __getitem__ Notes ----- This class implements the disjoint set [1]_, also known as the *union-find* or *merge-find* data structure. The *find* operation (implemented in `__getitem__`) implements the *path halving* variant. The *merge* method implements the *merge by size* variant. References ---------- .. [1] https://en.wikipedia.org/wiki/Disjoint-set_data_structure Examples -------- >>> from scipy.cluster.hierarchy import DisjointSet Initialize a disjoint set: >>> disjoint_set = DisjointSet([1, 2, 3, 'a', 'b']) Merge some subsets: >>> disjoint_set.merge(1, 2) True >>> disjoint_set.merge(3, 'a') True >>> disjoint_set.merge('a', 'b') True >>> disjoint_set.merge('b', 'b') False Find root elements: >>> disjoint_set[2] 1 >>> disjoint_set['b'] 3 Test connectivity: >>> disjoint_set.connected(1, 2) True >>> disjoint_set.connected(1, 'b') False List elements in disjoint set: >>> list(disjoint_set) [1, 2, 3, 'a', 'b'] Get the subset containing 'a': >>> disjoint_set.subset('a') {'a', 3, 'b'} Get all subsets in the disjoint set: >>> disjoint_set.subsets() [{1, 2}, {'a', 3, 'b'}] Nc � � d| _ i | _ i | _ i | _ i | _ |�|D ]}| � |� � �d S d S )N� )� n_subsets�_sizes�_parents�_nbrs�_indices�add)�self�elements�xs �:/usr/lib/python3/dist-packages/scipy/_lib/_disjoint_set.py�__init__zDisjointSet.__init__T s] � ������ ��� ��� ��� � � � � � ������ � � � � � � � � c �* � t | j � � S )zsReturns an iterator of the elements in the disjoint set. Elements are ordered by insertion order. )�iterr �r s r �__iter__zDisjointSet.__iter__` s � � �D�M�"�"�"r c �* � t | j � � S �N)�lenr r s r �__len__zDisjointSet.__len__g s � ��4�=�!�!�!r c � � || j v S r �r �r r s r � __contains__zDisjointSet.__contains__j s � ��D�M�!�!r c � � || j vrt |� � �| j }| j | | j || k r;||| ||< || }| j | | j || k �;|S )z�Find the root element of `x`. Parameters ---------- x : hashable object Input element. Returns ------- root : hashable object Root element of `x`. )r �KeyErrorr )r r �parentss r � __getitem__zDisjointSet.__getitem__m s� � � �D�M� !� !��1�+�+� � �-���m�A� �$�-��� �";�;�;� ����,�G�A�J��� �A� �m�A� �$�-��� �";�;�;� �r c � � || j v rdS d| j |< || j |< || j |< t | j � � | j |< | xj dz c_ dS )z(Add element `x` to disjoint set N� )r r r r r r r s r r zDisjointSet.add� sb � � �� � � � �F��� �A�� �� �a���� �1� � �t�}�-�-�� �a�� ���!�����r c � � | | }| | }| j | | j | k rdS | j }|| | j | f|| | j | fk r||}}|| j |< | j |xx | j | z cc< | j | | j | c| j |< | j |< | xj dz c_ dS )a� Merge the subsets of `x` and `y`. The smaller subset (the child) is merged into the larger subset (the parent). If the subsets are of equal size, the root element which was first inserted into the disjoint set is selected as the parent. Parameters ---------- x, y : hashable object Elements to merge. Returns ------- merged : bool True if `x` and `y` were in disjoint sets, False otherwise. Fr# T)r r r r r )r r �y�xr�yr�sizess r �mergezDisjointSet.merge� s� � �" �!�W�� �!�W�� �=�� �� �b� 1� 1� 1��5�� �� �"�I�t�}�R�(� )�U�2�Y�� �b�8I�,J� J� J����B� �� �b�� � �B����4�;�r�?�*����)-��B� ���B� �&�� �2��� �2�� ���!�����tr c �R � | j | | | j | | k S )a Test whether `x` and `y` are in the same subset. Parameters ---------- x, y : hashable object Elements to test. Returns ------- result : bool True if `x` and `y` are in the same set, False otherwise. r )r r r% s r � connectedzDisjointSet.connected� s% � � �}�T�!�W�%�� �t�A�w�)?�?�?r c �$ � || j vrt |� � �|g}| j | }| j | | j | k r>|� |� � | j | }| j | | j | k �>t |� � S )z�Get the subset containing `x`. Parameters ---------- x : hashable object Input element. Returns ------- result : set Subset containing `x`. )r r r �append�set)r r �result�nxts r �subsetzDisjointSet.subset� s� � � �D�M� !� !��1�+�+� �����j��m���m�C� �D�M�!�$4�4�4� �M�M�#� � � ��*�S�/�C� �m�C� �D�M�!�$4�4�4� �6�{�{�r c � � g }t � � }| D ]E}||vr?| � |� � }|� |� � |� |� � �F|S )z�Get all the subsets in the disjoint set. Returns ------- result : list Subsets in the disjoint set. )r. r1 �updater- )r r/ �visitedr �xsets r �subsetszDisjointSet.subsets� se � � ���%�%��� $� $�A��� � ��{�{�1�~�~�����t�$�$�$�� � �d�#�#�#��� r r )�__name__� __module__� __qualname__�__doc__r r r r r! r r) r+ r1 r6 � r r r r s� � � � � � �L� L�Z � � � �#� #� #�"� "� "�"� "� "�� � �. � � � � � �> @� @� @� � � �.� � � � r r N)r: r r; r r �<module>r< sK ��� � ^� ^� ^� ^� ^� ^� ^� ^� ^� ^r
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