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 = 1) ⇒ 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: 1) —

    of the edge



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# File 'lib/abuelo/edge.rb', line 25

def initialize(node_1, node_2, weight = 1)
  @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 10

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 13

def node_2
  @node_2
end

#weight ⇒ Numeric (readonly)

Returns weight.

Returns:

  • (Numeric) —

    weight



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# File 'lib/abuelo/edge.rb', line 16

def weight
  @weight
end

Instance Method Details

#<=>(other) ⇒ -1, ...

Comparison based on weight.

Parameters:

Returns:

  • (-1, 0, +1) 


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# File 'lib/abuelo/edge.rb', line 45

def <=>(other)
  weight <=> other.weight
end

#==(other) ⇒ 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 56

def ==(other)
  node_1 == other.node_1 &&
    node_2 == other.node_2 &&
    weight == other.weight
end

#symmetric ⇒ 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 34

def symmetric
  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 65

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