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graph::unionfind(3pm) [debian man page]

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

NAME

       Graph::UnionFind - union-find data structures

SYNOPSIS

	   use Graph::UnionFind;
	   my $uf = Graph::UnionFind->new;

	   # Add the vertices to the data structure.
	   $uf->add($u);
	   $uf->add($v);

	   # Join the partitions of the vertices.
	   $uf->union( $u, $v );

	   # Find the partitions the vertices belong to
	   # in the union-find data structure.	If they
	   # are equal, they are in the same partition.
	   # If the vertex has not been seen,
	   # undef is returned.
	   my $pu = $uf->find( $u );
	   my $pv = $uf->find( $v );
	   $uf->same($u, $v) # Equal to $pu eq $pv.

	   # Has the union-find seen this vertex?
	   $uf->has( $v )

DESCRIPTION

       Union-find is a special data structure that can be used to track the partitioning of a set into subsets (a problem known also as disjoint
       sets).

       Graph::UnionFind() is used for Graph::connected_components(), Graph::connected_component(), and Graph::same_connected_components() if you
       specify a true "union_find" parameter when you create an undirected graph.

       Note that union-find is one way: you cannot (easily) 'ununion' vertices once you have 'unioned' them.  This means that if you delete edges
       from a "union_find" graph, you will get wrong results from the Graph::connected_components(), Graph::connected_component(), and
       Graph::same_connected_components().

   API
       add
	       $uf->add($v)

	   Add the vertex v to the union-find.

       union
	       $uf->union($u, $v)

	   Add the edge u-v to the union-find.	Also implicitly adds the vertices.

       has
	       $uf->has($v)

	   Return true if the vertex v has been added to the union-find, false otherwise.

       find
	       $uf->find($v)

	   Return the union-find partition the vertex v belongs to, or "undef" if it has not been added.

       new
	       $uf = Graph::UnionFind->new()

	   The constructor.

       same
	       $uf->same($u, $v)

	   Return true of the vertices belong to the same union-find partition the vertex v belongs to, false otherwise.

AUTHOR AND COPYRIGHT

       Jarkko Hietaniemi jhi@iki.fi

LICENSE

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

perl v5.10.0							    2008-11-27						     Graph::UnionFind(3pm)

Check Out this Related Man Page

Graph::Writer::GraphViz(3pm)				User Contributed Perl Documentation			      Graph::Writer::GraphViz(3pm)

NAME

       Graph::Writer::GraphViz - GraphViz Writer for Graph object

SYNOPSIS

	 my @v = qw/Alice Bob Crude Dr/;
	 my $g = Graph->new(@v);

	 my $wr = Graph::Writer::GraphViz->new(-format => 'dot');
	 $wr->write_graph($g,'/tmp/graph.simple.dot');

	 my $wr_png = Graph::Writer::GraphViz->new(-format => 'png');
	 $wr_png->write_graph($g,'/tmp/graph.simple.png');

	 Graph::Writer::GraphViz->new(
	       -format => 'png',
	       -layout => 'twopi',
	       -ranksep => 1.5,
	       -fontsize => 8
	       -edge_color => 'grey',
	       -node_color => 'black',
	      )->write_graph($g,'/tmp/graph.png');

DESCRIPTION

       Graph::Writer::GraphViz is a class for writing out a Graph object with GraphViz module. All GraphViz formats should be supported without a
       problem.

METHODS

   new()
       Unlike other Graph::Writer modules, this module provide an extra parameter '-format' to new() method, in order to save different format.
       Other supported GraphViz parameters are -layout, -ranksep, -shape, -fontsize, -arrowsize.  Please see the SYNOPSIS for example usage.

       Valid format depends on those GraphViz as_fmt methods on your system, like, 'gif' if you have 'as_gif', 'text' if you can do 'as_text'.

SEE ALSO

       Graph, Graph::Writer, GraphViz

CREDITS

       Thanks for RURBAN@cpan.org for noticing tests failure on different platforms.

COPYRIGHT

       Copyright 2004 by Kang-min Liu <gugod@gugod.org>.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

       See <http://www.perl.com/perl/misc/Artistic.html>

perl v5.12.4							    2011-10-16					      Graph::Writer::GraphViz(3pm)
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