o `^h@ @sdZddlZddlmZddlmZddlmZm Z m Z e dd ge eddd d ge eddd d dgd d dddddZ  dddZ dS)zGraph utilities and algorithms.N)sparse)pairwise_distances)IntegralIntervalvalidate_paramsz array-likez sparse matrixleft)closed)graphsourcecutoffT)prefer_skip_nested_validation)r cCst|r |}nt|}i}d}|g}|rC|}t}|D]}||vr1|||<||j|q|dur=||kr= |S|d7}|s|S)aDReturn the length of the shortest path from source to all reachable nodes. Parameters ---------- graph : {array-like, sparse matrix} of shape (n_nodes, n_nodes) Adjacency matrix of the graph. Sparse matrix of format LIL is preferred. source : int Start node for path. cutoff : int, default=None Depth to stop the search - only paths of length <= cutoff are returned. Returns ------- paths : dict Reachable end nodes mapped to length of path from source, i.e. `{end: path_length}`. Examples -------- >>> from sklearn.utils.graph import single_source_shortest_path_length >>> import numpy as np >>> graph = np.array([[ 0, 1, 0, 0], ... [ 1, 0, 1, 0], ... [ 0, 1, 0, 0], ... [ 0, 0, 0, 0]]) >>> single_source_shortest_path_length(graph, 0) {0: 0, 1: 1, 2: 2} >>> graph = np.ones((6, 6)) >>> sorted(single_source_shortest_path_length(graph, 2).items()) [(0, 1), (1, 1), (2, 0), (3, 1), (4, 1), (5, 1)] rNr)rissparsetolil lil_matrixsetupdaterows)r r r seenlevel next_level this_levelvrQ/home/air/shanriGPT/back/venv/lib/python3.10/site-packages/sklearn/utils/graph.py"single_source_shortest_path_lengths( +   rdistance euclideancKs.|dkr t|r tdt|D]}t||k}||} t|D]q} t|| k} || } |dkr<|t|| } n t| | fd|i|} t| j dd| j \}}|dkrmd|||| |f<d|| |||f<q"|dkr| ||f|||| |f<| ||f|| |||f<q"t d |q|S) aAdd connections to sparse graph to connect unconnected components. For each pair of unconnected components, compute all pairwise distances from one component to the other, and add a connection on the closest pair of samples. This is a hacky way to get a graph with a single connected component, which is necessary for example to compute a shortest path between all pairs of samples in the graph. Parameters ---------- X : array of shape (n_samples, n_features) or (n_samples, n_samples) Features to compute the pairwise distances. If `metric = "precomputed"`, X is the matrix of pairwise distances. graph : sparse matrix of shape (n_samples, n_samples) Graph of connection between samples. n_connected_components : int Number of connected components, as computed by `scipy.sparse.csgraph.connected_components`. component_labels : array of shape (n_samples) Labels of connected components, as computed by `scipy.sparse.csgraph.connected_components`. mode : {'connectivity', 'distance'}, default='distance' Type of graph matrix: 'connectivity' corresponds to the connectivity matrix with ones and zeros, and 'distance' corresponds to the distances between neighbors according to the given metric. metric : str Metric used in `sklearn.metrics.pairwise.pairwise_distances`. kwargs : kwargs Keyword arguments passed to `sklearn.metrics.pairwise.pairwise_distances`. Returns ------- graph : sparse matrix of shape (n_samples, n_samples) Graph of connection between samples, with a single connected component. precomputedz_fix_connected_components with metric='precomputed' requires the full distance matrix in X, and does not work with a sparse neighbors graph.metricN)axis connectivityrrz?Unknown mode=%r, should be one of ['connectivity', 'distance'].) rr RuntimeErrorrangenp flatnonzeroix_r unravel_indexargminshape ValueError)Xr n_connected_componentscomponent_labelsmoder kwargsiidx_iXijidx_jXjDiijjrrr_fix_connected_componentsOs63  r:)rr) __doc__numpyr%scipyrmetrics.pairwiser_param_validationrrrrr:rrrrs   <