Graph::AdjacencyMatrix(3pm)				User Contributed Perl Documentation			       Graph::AdjacencyMatrix(3pm)

NAME

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

SYNOPSIS

	   use Graph::AdjacencyMatrix;
	   use Graph::Directed; # or Undirected

	   my $g  = Graph::Directed->new;
	   $g->add_...(); # build $g

	   my $am = Graph::AdjacencyMatrix->new($g);
	   $am->is_adjacent($u, $v)

	   my $am = Graph::AdjacencyMatrix->new($g, distance_matrix => 1);
	   $am->distance($u, $v)

	   my $am = Graph::AdjacencyMatrix->new($g, attribute_name => 'length');
	   $am->distance($u, $v)

	   my $am = Graph::AdjacencyMatrix->new($g, ...);
	   my @V  = $am->vertices();

DESCRIPTION

       You can use "Graph::AdjacencyMatrix" to compute the adjacency matrix and optionally also the distance matrix of a graph, and after that
       query the adjacencyness between vertices by using the "is_adjacent()" method, or query the distance between vertices by using the
       "distance()" method.

       By default the edge attribute used for distance is "w", but you can change that in new(), see below.

       If you modify the graph after creating the adjacency matrix of it, the adjacency matrix and the distance matrix may become invalid.

Methods
   Class Methods
       new($g)
	   Construct the adjacency matrix of the graph $g.

       new($g, options)
	   Construct the adjacency matrix of the graph $g with options as a hash.  The known options are

	   distance_matrix => boolean
		   By default only the adjacency matrix is computed.  To compute also the distance matrix, use the attribute "distance_matrix"
		   with a true value to the new() constructor.

	   attribute_name => attribute_name
		   By default the edge attribute used for distance is "w".  You can change that by giving another attribute name with the
		   "attribute_name" attribute to new() constructor.  Using this attribute also implicitly causes the distance matrix to be
		   computed.

   Object Methods
       is_adjacent($u, $v)
	   Return true if the vertex $v is adjacent to vertex $u, or false if not.

       distance($u, $v)
	   Return the distance between the vertices $u and $v, or "undef" if the vertices are not adjacent.

       adjacency_matrix
	   Return the adjacency matrix itself (a list of bitvector scalars).

       vertices
	   Return the list of vertices (useful for indexing the adjacency matrix).

ALGORITHM

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

SEE ALSO

       Graph::TransitiveClosure, Graph::BitMatrix

AUTHOR AND COPYRIGHT

       Jarkko Hietaniemi jhi@iki.fi

LICENSE

       This module is licensed under the same terms as Perl itself.

perl v5.10.0							    2005-04-16					       Graph::AdjacencyMatrix(3pm)