1Graph::AdjacencyMatrix(U3s)er Contributed Perl DocumentatGiroanph::AdjacencyMatrix(3)
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NAME

6       Graph::AdjacencyMatrix - create and query the adjacency matrix of graph
7       G
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SYNOPSIS

10           use Graph::AdjacencyMatrix;
11           use Graph::Directed; # or Undirected
12
13           my $g  = Graph::Directed->new;
14           $g->add_...(); # build $g
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16           my $am = Graph::AdjacencyMatrix->new($g);
17           $am->is_adjacent($u, $v)
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19           my $am = Graph::AdjacencyMatrix->new($g, distance_matrix => 1);
20           $am->distance($u, $v)
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22           my $am = Graph::AdjacencyMatrix->new($g, attribute_name => 'length');
23           $am->distance($u, $v)
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25           my $am = Graph::AdjacencyMatrix->new($g, ...);
26           my @V  = $am->vertices();
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28           $g = Graph->new(multiedged => 1);
29           $g->add_...(); # build $g
30           $am = Graph::AdjacencyMatrix->new($g, distance_matrix => 1);
31           $am->distance($u, $v) # returns hash-ref of ID => distance
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DESCRIPTION

34       You can use "Graph::AdjacencyMatrix" to compute the adjacency matrix
35       and optionally also the distance matrix of a graph, and after that
36       query the adjacencyness between vertices by using the is_adjacent()
37       method, or query the distance between vertices by using the distance()
38       method.
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40       By default the edge attribute used for distance is "w", but you can
41       change that in new(), see below.
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43       If you modify the graph after creating the adjacency matrix of it, the
44       adjacency matrix and the distance matrix may become invalid.
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Methods

47   Class Methods
48       new($g)
49           Construct the adjacency matrix of the graph $g.
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51       new($g, options)
52           Construct the adjacency matrix of the graph $g with options as a
53           hash.  The known options are
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55           distance_matrix => boolean
56                   By default only the adjacency matrix is computed.  To
57                   compute also the distance matrix, use the attribute
58                   "distance_matrix" with a true value to the new()
59                   constructor.
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61           attribute_name => attribute_name
62                   By default the edge attribute used for distance is "w".
63                   You can change that by giving another attribute name with
64                   the "attribute_name" attribute to new() constructor.  Using
65                   this attribute also implicitly causes the distance matrix
66                   to be computed.
67
68   Object Methods
69       is_adjacent($u, $v)
70           Return true if the vertex $v is adjacent to vertex $u, or false if
71           not.
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73       distance($u, $v)
74           Return the distance between the vertices $u and $v, or "undef" if
75           the vertices are not adjacent.
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77           If the underlying graph is multiedged, returns hash-ref of ID
78           mapped to distance. If a given edge ID does not have the attribute
79           defined, it will not be represented. If no edge IDs have the
80           attribute, "undef" will be returned.
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82       adjacency_matrix
83           Return the adjacency matrix itself (a list of bitvector scalars).
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85       vertices
86           Return the list of vertices (useful for indexing the adjacency
87           matrix).
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ALGORITHM

90       The algorithm used to create the matrix is two nested loops, which is
91       O(V**2) in time, and the returned matrices are O(V**2) in space.
92

SEE ALSO

94       Graph::TransitiveClosure, Graph::BitMatrix
95

97       Jarkko Hietaniemi jhi@iki.fi
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LICENSE

100       This module is licensed under the same terms as Perl itself.
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104perl v5.38.0                      2023-07-25         Graph::AdjacencyMatrix(3)
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