Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/networkx/generators/triads.py: 50%

1# See https://github.com/networkx/networkx/pull/1474 

2# Copyright 2011 Reya Group <http://www.reyagroup.com> 

3# Copyright 2011 Alex Levenson <alex@isnotinvain.com> 

4# Copyright 2011 Diederik van Liere <diederik.vanliere@rotman.utoronto.ca> 

5"""Functions that generate the triad graphs, that is, the possible 

6digraphs on three nodes. 

7 

8""" 

9 

10import networkx as nx 

11from networkx.classes import DiGraph 

12 

13__all__ = ["triad_graph"] 

14 

15#: Dictionary mapping triad name to list of directed edges in the 

16#: digraph representation of that triad (with nodes 'a', 'b', and 'c'). 

17TRIAD_EDGES = { 

18 "003": [], 

19 "012": ["ab"], 

20 "102": ["ab", "ba"], 

21 "021D": ["ba", "bc"], 

22 "021U": ["ab", "cb"], 

23 "021C": ["ab", "bc"], 

24 "111D": ["ac", "ca", "bc"], 

25 "111U": ["ac", "ca", "cb"], 

26 "030T": ["ab", "cb", "ac"], 

27 "030C": ["ba", "cb", "ac"], 

28 "201": ["ab", "ba", "ac", "ca"], 

29 "120D": ["bc", "ba", "ac", "ca"], 

30 "120U": ["ab", "cb", "ac", "ca"], 

31 "120C": ["ab", "bc", "ac", "ca"], 

32 "210": ["ab", "bc", "cb", "ac", "ca"], 

33 "300": ["ab", "ba", "bc", "cb", "ac", "ca"], 

34} 

35 

36 

37@nx._dispatchable(graphs=None, returns_graph=True) 

38def triad_graph(triad_name): 

39 """Returns the triad graph with the given name. 

40 

41 Each string in the following tuple is a valid triad name:: 

42 

43 ( 

44 "003", 

45 "012", 

46 "102", 

47 "021D", 

48 "021U", 

49 "021C", 

50 "111D", 

51 "111U", 

52 "030T", 

53 "030C", 

54 "201", 

55 "120D", 

56 "120U", 

57 "120C", 

58 "210", 

59 "300", 

60 ) 

61 

62 Each triad name corresponds to one of the possible valid digraph on 

63 three nodes. 

64 

65 Parameters 

66 ---------- 

67 triad_name : string 

68 The name of a triad, as described above. 

69 

70 Returns 

71 ------- 

72 :class:`~networkx.DiGraph` 

73 The digraph on three nodes with the given name. The nodes of the 

74 graph are the single-character strings 'a', 'b', and 'c'. 

75 

76 Raises 

77 ------ 

78 ValueError 

79 If `triad_name` is not the name of a triad. 

80 

81 See also 

82 -------- 

83 triadic_census 

84 

85 """ 

86 if triad_name not in TRIAD_EDGES: 

87 raise ValueError( 

88 f'unknown triad name "{triad_name}"; use one of the triad names' 

89 " in the TRIAD_NAMES constant" 

90 ) 

91 G = DiGraph() 

92 G.add_nodes_from("abc") 

93 G.add_edges_from(TRIAD_EDGES[triad_name]) 

94 return G