Module: Jumoku::Strategies::SimpleEdgeLabeling

Includes:
EdgeLabelingBackend
Defined in:
lib/jumoku/strategies/edge_labeling/simple.rb

Overview

A simple edge labeling strategy: as new nodes are added, new edges are assigned increasing integers. Removed edges do not trigger reindexing, so for a tree with n nodes, the labeling set is ||n|| but indexes are not necessarily < n (indexing starts from 0).

This simple strategy allows for using simple search algorithms as well for simple ordering schemes.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#next_simple_edge_label_number ⇒ Object

Returns the value of attribute next_simple_edge_label_number.



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# File 'lib/jumoku/strategies/edge_labeling/simple.rb', line 14

def next_simple_edge_label_number
  @next_simple_edge_label_number
end

Instance Method Details

#add_branch!(u, v = nil, l = nil) ⇒ Object

Override to handle an iterator for simple edge labeling. When a branch is added, it is labeled with an OpenHash with one :_weight key which value is an increasing integer. One may pass any custom label to the method, which will be available under the :label key of the hash.



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# File 'lib/jumoku/strategies/edge_labeling/simple.rb', line 21

def add_branch!(u, v = nil, l = nil)
  self.next_simple_edge_label_number ||= 0
  label = OpenHash.new(:_weight => self.next_simple_edge_label_number)
  label.label = l unless l.nil?
  super(u, v, label)
  _edge_labeling_inc
end

#sort_edges(set) ⇒ Array

Sort a set of edges.

Parameters:

Returns:



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# File 'lib/jumoku/strategies/edge_labeling/simple.rb', line 44

def sort_edges(set)
  _sort_edges(set)
end

#sorted_arcs_from(node) ⇒ Array<Plexus::Arc> Also known as: sorted_edges_from

Only for directed trees.

Return the sorted list of arcs branched out from the specified node.

Parameters:

  • node (Node)

Returns:



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# File 'lib/jumoku/strategies/edge_labeling/simple.rb', line 55

def sorted_arcs_from(node)
  return nil unless is_a? RawDirectedTreeBuilder
  adjacent(node).map do |child_node|
    edge_class[node, child_node, edge_label(node, child_node)]
  end.sort_by { |e| e.label._weight }
end

#sorted_children_of(node) ⇒ Array<Node>

Only for directed trees.

Return the sorted list of nodes branched out from the specified node.

Parameters:

  • node (Node)

Returns:



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# File 'lib/jumoku/strategies/edge_labeling/simple.rb', line 70

def sorted_children_of(node)
  return nil unless is_a? RawDirectedTreeBuilder
  sorted_edges_from(node).map { |edge| edge.target }
end

#sorted_edges(&block) ⇒ Array

Sort edges by increasing weight number. If a block is provided, rely on the backend implementation (#sort_by).

Returns:



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# File 'lib/jumoku/strategies/edge_labeling/simple.rb', line 34

def sorted_edges(&block)
  return super(&block) if block_given?
  _sort_edges(edges)
end