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Graph-Weighted-0.9101
River stage zero No dependents
/ Graph::Weighted

NAME

Graph::Weighted - A weighted graph implementation

VERSION

version 0.9101

SYNOPSIS


            

              
              
use Graph::Weighted;
my $gw = Graph::Weighted->new;
$gw->populate(
   [ [ 0,1,2,0,0 ], # Vertex 0 with 2 edges of weight 3
     [ 1,0,3,0,0 ], #    "   1      2 "               4
     [ 2,3,0,0,0 ], #    "   2      2 "               5
     [ 0,0,1,0,0 ], #    "   3      1 "               1
     [ 0,0,0,0,0 ], #    "   4      0 "               0
   ]
);
$gw->dump;
my ( $lightest, $heaviest ) = $gw->vertex_span;
( $lightest, $heaviest ) = $gw->edge_span;
my $attr = 'probability';
$gw = Graph::Weighted->new;
$gw->populate(
   {
       0 => { label => 'A', 1=>0.4, 3=>0.6 },
       1 => { label => 'B', 0=>0.3, 2=>0.7 },
       2 => { label => 'C', 0=>0.5, 2=>0.5 },
       3 => { label => 'D', 0=>0.2, 1=>0.8 },
   },
   $attr
);
$gw->dump($attr);
my $cost = $gw->get_cost( [0, 1], $attr );
$cost = $gw->path_cost( [0, 3, 1, 2], $attr );
my $tree = $gw->MST_Kruskal;
my $sum = $gw->MST_edge_sum($tree);

DESCRIPTION

A Graph::Weighted object is a subclass of the Graph module with attribute handling. As such, all of the Graph methods may be used.

METHODS

new


            

              
              
my $gw = Graph::Weighted->new;
my $gw = Graph::Weighted->new(%arguments);

Return a new Graph::Weighted object.

Please see "Constructors" in Graph for the possible constructor arguments.

populate


            

              
              
$gw->populate($matrix);
$gw->populate($matrix, $attribute);
$gw->populate(\@vectors);
$gw->populate(\@vectors, $attribute);
$gw->populate(\%data_points);
$gw->populate(\%data_points, $attribute);

Populate a graph with weighted nodes and edges.

The data can be an arrayref of numeric vectors, a Math::Matrix object, a Math::MatrixReal object, or a hashref of node-edge values.

Data given as a hash reference may also contain node labels. Also, the keys need not be numeric, just unique.

The optional attribute argument is a string with the default weight.

get_cost


            

              
              
$c = $gw->get_cost($vertex);
$c = $gw->get_cost($vertex, $attribute);
$c = $gw->get_cost(\@edge);
$c = $gw->get_cost(\@edge, $attribute);

Return the named attribute value for the vertex or edge. If no attribute name is given, the string weight is used.

vertex_span


            

              
              
($lightest, $heaviest) = $gw->vertex_span;
($lightest, $heaviest) = $gw->vertex_span($attr);

Return the lightest and heaviest vertices as array references.

edge_span


            

              
              
($lightest, $heaviest) = $gw->edge_span;
($lightest, $heaviest) = $gw->edge_span($attr);

Return the lightest and heaviest edges as array references.

path_cost


            

              
              
$c = $gw->path_cost(\@vertices);
$c = $gw->path_cost(\@vertices, $attr);

Return the summed weight (or cost attribute) of the path edges.

MST_edge_sum


            

              
              
$sum = $gw->MST_edge_sum($tree);

Compute the sum of the edges of a minimum-spanning-tree.

dump


            

              
              
$gw->dump
$gw->dump($attr)

Print out the graph showing vertices, edges and costs.

SEE ALSO

Graph, the parent of this module

Graph::Easy::Weighted, the sibling

The eg/* and t/* programs in this distribution

AUTHOR

Gene Boggs <gene@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2020 by Gene Boggs.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.