Source code for sknetwork.utils.ward

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
Created on October 2019
@author: Nathan de Lara <>
import numpy as np
from scipy.cluster.hierarchy import ward

from sknetwork.utils.base import Algorithm

[docs]class WardDense(Algorithm): """Hierarchical clustering by the Ward method based on SciPy. Attributes ---------- dendrogram_ : np.ndarray (n - 1, 4) Dendrogram. References ---------- * Ward, J. H., Jr. (1963). Hierarchical grouping to optimize an objective function. Journal of the American Statistical Association, 58, 236–244. * Murtagh, F., & Contreras, P. (2012). Algorithms for hierarchical clustering: an overview. Wiley Interdisciplinary Reviews: Data Mining and Knowledge Discovery, 2(1), 86-97. """ def __init__(self): self.dendrogram_ = None
[docs] def fit(self, x: np.ndarray) -> 'WardDense': """Apply algorithm to a dense matrix. Parameters ---------- x: Data to cluster. Returns ------- self: :class:`WardDense` """ self.dendrogram_ = ward(x) return self
[docs] def fit_transform(self, x: np.ndarray) -> np.ndarray: """Apply algorithm to a dense matrix and return the dendrogram. Parameters ---------- x: Data to cluster. Returns ------- dendrogram: np.ndarray """ return self.dendrogram_