NAME
Graph::Easy::Weighted - A weighted graph implementation
VERSION
version 0.0501
SYNOPSIS
use Graph::Easy::Weighted;
my $gw = Graph::Easy::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
]
);
for my $vertex ( $gw->vertices ) {
printf "vertex: %s weight=%.2f\n",
$vertex->name, $gw->get_cost($vertex);
for my $edge ( $gw->edges ) {
next if $edge->from->name ne $vertex->name;
printf "\tedge to: %s weight=%.2f\n",
$edge->to->name, $gw->get_cost($edge);
}
}
my ($lightest, $heaviest) = $gw->vertex_span();
($lightest, $heaviest) = $gw->edge_span();
my $weight = $gw->path_cost(\@vertices);
my $attr = 'probability';
$gw = Graph::Easy::Weighted->new();
$gw->populate(
{
0 => { attributes => { title => 'A' }, 1=>0.4, 3=>0.6 },
1 => { attributes => { title => 'B' }, 0=>0.3, 2=>0.7 },
2 => { attributes => { title => 'C' }, 0=>0.5, 2=>0.5 },
3 => { attributes => { title => 'D' }, 0=>0.2, 1=>0.8 },
},
$attr,
'%0.2f'
);
for my $vertex ( $gw->vertices ) {
printf "%s vertex: %s %s=%s\n",
$vertex->title, $vertex->name, $attr, $gw->get_cost($vertex, $attr);
for my $edge ( $gw->edges ) {
next if $edge->from->name ne $vertex->name;
printf "\tedge to: %s %s=%s\n",
$edge->to->name, $attr, $gw->get_cost($edge, $attr);
}
}DESCRIPTION
A Graph::Easy::Weighted object is a subclass of the Graph::Easy module with attribute handling. As such, all of the Graph::Easy methods may be used as documented, but with the addition of custom weighting.
METHODS
new()
my $gw = Graph::Easy::Weighted->new;Return a new Graph::Easy::Weighted object.
Please see "new()" in Graph::Easy for the possible constructor arguments.
populate()
$gw->populate($matrix);
$gw->populate($matrix, $attribute);
$gw->populate(\@vectors);
$gw->populate(\@vectors, $attribute);
$gw->populate(\%data);
$gw->populate(\%data, $attribute);
$gw->populate(\%data, $attribute, $format);Populate a graph with weighted nodes.
The data can be an arrayref of numeric vectors, a Math::MatrixReal object, or a hashref of numeric edge values.
Data given as a hash reference may contain node attributes as shown in the SYNOPSIS. See Graph::Easy::Manual for the available attributes.
The optional edge attribute argument is a string, with the default "weight."
Multiple attributes may populate a single graph, thereby layering and increasing the overall dimension.
An optional sprintf format string may be provided for the edge label.
Examples of vertices in array reference form:
[] 1 vertex with no edges.
[0] 1 vertex with no edges.
[1] 1 vertex and 1 edge to itself, weight 1.
[0,1] 2 vertices and 1 edge, weight 1.
[1,0,9] 3 vertices and 2 edges having, weight 10.
[1,2,3] 3 vertices and 3 edges having, weight 6.get_cost()
$c = $gw->get_cost($vertex);
$c = $gw->get_cost($vertex, $attribute);
$c = $gw->get_cost($edge);
$c = $gw->get_cost($edge, $attribute);Return the weight or named attribute value for the vertex or edge.
vertex_span()
my ($lightest, $heaviest) = $gw->vertex_span();
my ($lightest, $heaviest) = $gw->vertex_span($attr);Return the lightest and heaviest vertices.
edge_span()
my ($lightest, $heaviest) = $gw->edge_span();
my ($lightest, $heaviest) = $gw->edge_span($attr);Return the lightest to heaviest edges.
path_cost()
my $weight = $gw->path_cost(\@named_vertices);
my $weight = $gw->path_cost(\@named_vertices, $attr);Return the summed weight (or given cost attribute) of the path edges.
For shortest paths and minimum spanning trees, please see "EXAMPLES" in Graph::Weighted.
SEE ALSO
Graph::Easy, the parent of this module
Graph::Weighted, the sibling
The eg/* and t/* file sources
AUTHOR
Gene Boggs <gene@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2015 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.