import pytest np = pytest.importorskip("numpy") pytest.importorskip("scipy") import networkx as nx from networkx.exception import NetworkXError from networkx.generators.degree_seq import havel_hakimi_graph def test_incidence_matrix_simple(): deg = [3, 2, 2, 1, 0] G = havel_hakimi_graph(deg) deg = [(1, 0), (1, 0), (1, 0), (2, 0), (1, 0), (2, 1), (0, 1), (0, 1)] MG = nx.random_clustered_graph(deg, seed=42) I = nx.incidence_matrix(G).todense().astype(int) # fmt: off expected = np.array( [[1, 1, 1, 0], [0, 1, 0, 1], [1, 0, 0, 1], [0, 0, 1, 0], [0, 0, 0, 0]] ) # fmt: on np.testing.assert_equal(I, expected) I = nx.incidence_matrix(MG).todense().astype(int) # fmt: off expected = np.array( [[1, 0, 0, 0, 0, 0, 0], [1, 0, 0, 0, 0, 0, 0], [0, 1, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0], [0, 1, 0, 0, 0, 0, 0], [0, 0, 0, 0, 1, 1, 0], [0, 0, 0, 0, 0, 1, 1], [0, 0, 0, 0, 1, 0, 1]] ) # fmt: on np.testing.assert_equal(I, expected) with pytest.raises(NetworkXError): nx.incidence_matrix(G, nodelist=[0, 1]) class TestGraphMatrix: @classmethod def setup_class(cls): deg = [3, 2, 2, 1, 0] cls.G = havel_hakimi_graph(deg) # fmt: off cls.OI = np.array( [[-1, -1, -1, 0], [1, 0, 0, -1], [0, 1, 0, 1], [0, 0, 1, 0], [0, 0, 0, 0]] ) cls.A = np.array( [[0, 1, 1, 1, 0], [1, 0, 1, 0, 0], [1, 1, 0, 0, 0], [1, 0, 0, 0, 0], [0, 0, 0, 0, 0]] ) # fmt: on cls.WG = havel_hakimi_graph(deg) cls.WG.add_edges_from( (u, v, {"weight": 0.5, "other": 0.3}) for (u, v) in cls.G.edges() ) # fmt: off cls.WA = np.array( [[0, 0.5, 0.5, 0.5, 0], [0.5, 0, 0.5, 0, 0], [0.5, 0.5, 0, 0, 0], [0.5, 0, 0, 0, 0], [0, 0, 0, 0, 0]] ) # fmt: on cls.MG = nx.MultiGraph(cls.G) cls.MG2 = cls.MG.copy() cls.MG2.add_edge(0, 1) # fmt: off cls.MG2A = np.array( [[0, 2, 1, 1, 0], [2, 0, 1, 0, 0], [1, 1, 0, 0, 0], [1, 0, 0, 0, 0], [0, 0, 0, 0, 0]] ) cls.MGOI = np.array( [[-1, -1, -1, -1, 0], [1, 1, 0, 0, -1], [0, 0, 1, 0, 1], [0, 0, 0, 1, 0], [0, 0, 0, 0, 0]] ) # fmt: on cls.no_edges_G = nx.Graph([(1, 2), (3, 2, {"weight": 8})]) cls.no_edges_A = np.array([[0, 0], [0, 0]]) def test_incidence_matrix(self): "Conversion to incidence matrix" I = ( nx.incidence_matrix( self.G, nodelist=sorted(self.G), edgelist=sorted(self.G.edges()), oriented=True, ) .todense() .astype(int) ) np.testing.assert_equal(I, self.OI) I = ( nx.incidence_matrix( self.G, nodelist=sorted(self.G), edgelist=sorted(self.G.edges()), oriented=False, ) .todense() .astype(int) ) np.testing.assert_equal(I, np.abs(self.OI)) I = ( nx.incidence_matrix( self.MG, nodelist=sorted(self.MG), edgelist=sorted(self.MG.edges()), oriented=True, ) .todense() .astype(int) ) np.testing.assert_equal(I, self.OI) I = ( nx.incidence_matrix( self.MG, nodelist=sorted(self.MG), edgelist=sorted(self.MG.edges()), oriented=False, ) .todense() .astype(int) ) np.testing.assert_equal(I, np.abs(self.OI)) I = ( nx.incidence_matrix( self.MG2, nodelist=sorted(self.MG2), edgelist=sorted(self.MG2.edges()), oriented=True, ) .todense() .astype(int) ) np.testing.assert_equal(I, self.MGOI) I = ( nx.incidence_matrix( self.MG2, nodelist=sorted(self.MG), edgelist=sorted(self.MG2.edges()), oriented=False, ) .todense() .astype(int) ) np.testing.assert_equal(I, np.abs(self.MGOI)) def test_weighted_incidence_matrix(self): I = ( nx.incidence_matrix( self.WG, nodelist=sorted(self.WG), edgelist=sorted(self.WG.edges()), oriented=True, ) .todense() .astype(int) ) np.testing.assert_equal(I, self.OI) I = ( nx.incidence_matrix( self.WG, nodelist=sorted(self.WG), edgelist=sorted(self.WG.edges()), oriented=False, ) .todense() .astype(int) ) np.testing.assert_equal(I, np.abs(self.OI)) # np.testing.assert_equal(nx.incidence_matrix(self.WG,oriented=True, # weight='weight').todense(),0.5*self.OI) # np.testing.assert_equal(nx.incidence_matrix(self.WG,weight='weight').todense(), # np.abs(0.5*self.OI)) # np.testing.assert_equal(nx.incidence_matrix(self.WG,oriented=True,weight='other').todense(), # 0.3*self.OI) I = nx.incidence_matrix( self.WG, nodelist=sorted(self.WG), edgelist=sorted(self.WG.edges()), oriented=True, weight="weight", ).todense() np.testing.assert_equal(I, 0.5 * self.OI) I = nx.incidence_matrix( self.WG, nodelist=sorted(self.WG), edgelist=sorted(self.WG.edges()), oriented=False, weight="weight", ).todense() np.testing.assert_equal(I, np.abs(0.5 * self.OI)) I = nx.incidence_matrix( self.WG, nodelist=sorted(self.WG), edgelist=sorted(self.WG.edges()), oriented=True, weight="other", ).todense() np.testing.assert_equal(I, 0.3 * self.OI) # WMG=nx.MultiGraph(self.WG) # WMG.add_edge(0,1,weight=0.5,other=0.3) # np.testing.assert_equal(nx.incidence_matrix(WMG,weight='weight').todense(), # np.abs(0.5*self.MGOI)) # np.testing.assert_equal(nx.incidence_matrix(WMG,weight='weight',oriented=True).todense(), # 0.5*self.MGOI) # np.testing.assert_equal(nx.incidence_matrix(WMG,weight='other',oriented=True).todense(), # 0.3*self.MGOI) WMG = nx.MultiGraph(self.WG) WMG.add_edge(0, 1, weight=0.5, other=0.3) I = nx.incidence_matrix( WMG, nodelist=sorted(WMG), edgelist=sorted(WMG.edges(keys=True)), oriented=True, weight="weight", ).todense() np.testing.assert_equal(I, 0.5 * self.MGOI) I = nx.incidence_matrix( WMG, nodelist=sorted(WMG), edgelist=sorted(WMG.edges(keys=True)), oriented=False, weight="weight", ).todense() np.testing.assert_equal(I, np.abs(0.5 * self.MGOI)) I = nx.incidence_matrix( WMG, nodelist=sorted(WMG), edgelist=sorted(WMG.edges(keys=True)), oriented=True, weight="other", ).todense() np.testing.assert_equal(I, 0.3 * self.MGOI) def test_adjacency_matrix(self): "Conversion to adjacency matrix" np.testing.assert_equal(nx.adjacency_matrix(self.G).todense(), self.A) np.testing.assert_equal(nx.adjacency_matrix(self.MG).todense(), self.A) np.testing.assert_equal(nx.adjacency_matrix(self.MG2).todense(), self.MG2A) np.testing.assert_equal( nx.adjacency_matrix(self.G, nodelist=[0, 1]).todense(), self.A[:2, :2] ) np.testing.assert_equal(nx.adjacency_matrix(self.WG).todense(), self.WA) np.testing.assert_equal( nx.adjacency_matrix(self.WG, weight=None).todense(), self.A ) np.testing.assert_equal( nx.adjacency_matrix(self.MG2, weight=None).todense(), self.MG2A ) np.testing.assert_equal( nx.adjacency_matrix(self.WG, weight="other").todense(), 0.6 * self.WA ) np.testing.assert_equal( nx.adjacency_matrix(self.no_edges_G, nodelist=[1, 3]).todense(), self.no_edges_A, )