Class: Abuelo::Edge

Inherits:
Object
  • Object
show all
Defined in:
lib/abuelo/edge.rb

Overview

Class Edge provides a representation of an edge. An edge connects two nodes(start-node and end-node) and has a weight.

Author:

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(node_1, node_2, weight = 0) ⇒ Edge

Initialiazises the edge with its two nodes and its weight.

Parameters:

  • node_1 (Abuelo::Node) —

    start-node

  • node_2 (Abuelo::Node) —

    end-node

  • weight (Numeric) (defaults to: 0) —

    of the edge



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# File 'lib/abuelo/edge.rb', line 26

def initialize(node_1, node_2, weight = 0)
  @node_1 = node_1
  @node_2 = node_2
  @weight = weight
end

Instance Attribute Details

#node_1 ⇒ Abuelo::Node (readonly)

Returns start-node.

Returns:



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# File 'lib/abuelo/edge.rb', line 11

def node_1
  @node_1
end

#node_2 ⇒ Abuelo::Node (readonly)

Returns end-node.

Returns:



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# File 'lib/abuelo/edge.rb', line 14

def node_2
  @node_2
end

#weight ⇒ Numeric (readonly)

Returns weight.

Returns:

  • (Numeric) —

    weight



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# File 'lib/abuelo/edge.rb', line 17

def weight
  @weight
end

Instance Method Details

#<=>(other_edge) ⇒ -1, ...

Comparison based on weight.

Parameters:

Returns:

  • (-1, 0, +1 or ni) 


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# File 'lib/abuelo/edge.rb', line 46

def <=>(other_edge)
  self.weight <=> other_edge.weight
end

#==(other_edge) ⇒ Boolean

Equality check.

Parameters:

Returns:

  • (Boolean) —

    true if start-, end-node and weight of both edges are equal



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# File 'lib/abuelo/edge.rb', line 57

def ==(other_edge)
  self.node_1 == other_edge.node_1 &&
  self.node_2 == other_edge.node_2 &&
  self.weight == other_edge.weight
end

#opposite ⇒ Abuelo::Edge

Returns a new edge with same weight but reversed start- and end-node.

Returns:

  • (Abuelo::Edge) —

    a new edge with same weight but reversed start- and end-node.



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# File 'lib/abuelo/edge.rb', line 35

def opposite
  Abuelo::Edge.new(node_2, node_1, weight)
end

#to_s ⇒ String

Returns human readable representation of edge.

Returns:

  • (String) —

    human readable representation of edge



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# File 'lib/abuelo/edge.rb', line 66

def to_s
  "#{node_1.to_s} -> #{node_2.to_s} with weight #{weight}"
end