1Graph::TransitiveClosurUes(e3r)Contributed Perl DocumentGartaipohn::TransitiveClosure(3)
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NAME

6       Graph::TransitiveClosure - create and query transitive closure of graph
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SYNOPSIS

9           use Graph::TransitiveClosure;
10           use Graph::Directed; # or Undirected
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12           my $g  = Graph::Directed->new;
13           $g->add_...(); # build $g
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15           # Compute the transitive closure graph.
16           my $tcg = Graph::TransitiveClosure->new($g);
17           $tcg->is_reachable($u, $v) # Identical to $tcg->has_edge($u, $v)
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19           # Being reflexive is the default, meaning that null transitions
20           # (transitions from a vertex to the same vertex) are included.
21           my $tcg = Graph::TransitiveClosure->new($g, reflexive => 1);
22           my $tcg = Graph::TransitiveClosure->new($g, reflexive => 0);
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24           # is_reachable(u, v) is always reflexive.
25           $tcg->is_reachable($u, $v)
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27           # You can check any graph for transitivity.
28           $g->is_transitive()
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30           my $tcg = Graph::TransitiveClosure->new($g, path_length => 1);
31           $tcg->path_length($u, $v)
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33           # path_vertices is automatically always on so this is a no-op.
34           my $tcg = Graph::TransitiveClosure->new($g, path_vertices => 1);
35           $tcg->path_vertices($u, $v)
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37           # Both path_length and path_vertices.
38           my $tcg = Graph::TransitiveClosure->new($g, path => 1);
39           $tcg->path_vertices($u, $v)
40           $tcg->length($u, $v)
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42           my $tcg = Graph::TransitiveClosure->new($g, attribute_name => 'length');
43           $tcg->path_length($u, $v)
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DESCRIPTION

46       You can use "Graph::TransitiveClosure" to compute the transitive
47       closure graph of a graph and optionally also the minimum paths (lengths
48       and vertices) between vertices, and after that query the transitiveness
49       between vertices by using the "is_reachable()" and "is_transitive()"
50       methods, and the paths by using the "path_length()" and
51       "path_vertices()" methods.
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53       For further documentation, see the Graph::TransitiveClosure::Matrix.
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55   Class Methods
56       new($g, %opt)
57           Construct a new transitive closure object.  Note that strictly
58           speaking the returned object is not a graph; it is a graph plus
59           other stuff.  But you should be able to use it as a graph plus a
60           couple of methods inherited from the
61           Graph::TransitiveClosure::Matrix class.
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63   Object Methods
64       These are only the methods 'native' to the class: see
65       Graph::TransitiveClosure::Matrix for more.
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67       is_transitive($g)
68           Return true if the Graph $g is transitive.
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70       transitive_closure_matrix
71           Return the transitive closure matrix of the transitive closure
72           object.
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74   INTERNALS
75       The transitive closure matrix is stored as an attribute of the graph
76       called "_tcm", and any methods not found in the graph class are
77       searched in the transitive closure matrix class.
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81perl v5.28.1                      2015-09-22       Graph::TransitiveClosure(3)
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