Source code for sknetwork.clustering.postprocess

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
Created on July 10, 2019
@author: Nathan de Lara <>
@author: Thomas Bonald <>
from typing import Optional

import numpy as np
from scipy import sparse

from sknetwork.utils.membership import get_membership

[docs]def reindex_labels(labels: np.ndarray) -> np.ndarray: """Reindex clusters in decreasing order of size. Parameters ---------- labels : Label of each node. Returns ------- new_labels : np.ndarray New label of each node. Example ------- >>> from sknetwork.clustering import reindex_labels >>> labels = np.array([0, 1, 1]) >>> reindex_labels(labels) array([1, 0, 0]) """ _, index, counts = np.unique(labels, return_inverse=True, return_counts=True) _, new_index = np.unique(np.argsort(-counts), return_index=True) return new_index[index]
[docs]def aggregate_graph(input_matrix: sparse.csr_matrix, labels: Optional[np.ndarray] = None, labels_row: Optional[np.ndarray] = None, labels_col: Optional[np.ndarray] = None) \ -> sparse.csr_matrix: """Aggregate graph per label. All nodes with the same label become a single node. Negative labels are ignored (corresponding nodes are discarded). Parameters ---------- input_matrix: sparse matrix Adjacency or biadjacency matrix of the graph. labels: np.ndarray Labels of nodes. labels_row: np.ndarray Labels of rows (for bipartite graphs). Alias for labels. labels_col: np.ndarray Labels of columns (for bipartite graphs). """ if labels_row is not None: membership_row = get_membership(labels_row) else: membership_row = get_membership(labels) if labels_col is not None: membership_col = get_membership(labels_col) else: membership_col = membership_row aggregate_matrix = return aggregate_matrix.tocsr()