Source code for dgl.data.karate

"""KarateClub Dataset
"""
import networkx as nx
import numpy as np

from .. import backend as F
from ..convert import from_networkx
from .dgl_dataset import DGLDataset
from .utils import deprecate_property

__all__ = ["KarateClubDataset", "KarateClub"]


[docs]class KarateClubDataset(DGLDataset): r"""Karate Club dataset for Node Classification Zachary's karate club is a social network of a university karate club, described in the paper "An Information Flow Model for Conflict and Fission in Small Groups" by Wayne W. Zachary. The network became a popular example of community structure in networks after its use by Michelle Girvan and Mark Newman in 2002. Official website: `<http://konect.cc/networks/ucidata-zachary/>`_ Karate Club dataset statistics: - Nodes: 34 - Edges: 156 - Number of Classes: 2 Parameters ---------- transform : callable, optional A transform that takes in a :class:`~dgl.DGLGraph` object and returns a transformed version. The :class:`~dgl.DGLGraph` object will be transformed before every access. Attributes ---------- num_classes : int Number of node classes Examples -------- >>> dataset = KarateClubDataset() >>> num_classes = dataset.num_classes >>> g = dataset[0] >>> labels = g.ndata['label'] """ def __init__(self, transform=None): super(KarateClubDataset, self).__init__( name="karate_club", transform=transform ) def process(self): kc_graph = nx.karate_club_graph() label = np.asarray( [kc_graph.nodes[i]["club"] != "Mr. Hi" for i in kc_graph.nodes] ).astype(np.int64) label = F.tensor(label) g = from_networkx(kc_graph) g.ndata["label"] = label self._graph = g self._data = [g] @property def num_classes(self): """Number of classes.""" return 2
[docs] def __getitem__(self, idx): r"""Get graph object Parameters ---------- idx : int Item index, KarateClubDataset has only one graph object Returns ------- :class:`dgl.DGLGraph` graph structure and labels. - ``ndata['label']``: ground truth labels """ assert idx == 0, "This dataset has only one graph" if self._transform is None: return self._graph else: return self._transform(self._graph)
[docs] def __len__(self): r"""The number of graphs in the dataset.""" return 1
KarateClub = KarateClubDataset