Class: Node

Inherits:
Object show all
Defined in:
lib/k_means/node.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(position, similarity_measure) ⇒ Node

Returns a new instance of Node.



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# File 'lib/k_means/node.rb', line 15

def initialize(position, similarity_measure)
  @position = position
  @similarity_measure = similarity_measure
end

Instance Attribute Details

#best_distance ⇒ Object

Returns the value of attribute best_distance.



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# File 'lib/k_means/node.rb', line 13

def best_distance
  @best_distance
end

#closest_centroid ⇒ Object

Returns the value of attribute closest_centroid.



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# File 'lib/k_means/node.rb', line 13

def closest_centroid
  @closest_centroid
end

#position ⇒ Object

Returns the value of attribute position.



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# File 'lib/k_means/node.rb', line 13

def position
  @position
end

Class Method Details

.create_nodes(data, similarity_measure) ⇒ Object 



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# File 'lib/k_means/node.rb', line 4

def create_nodes(data, similarity_measure)
  nodes = []
  data.each do |position|
    nodes << new(position, similarity_measure)
  end
  nodes
end

Instance Method Details

#reset! ⇒ Object 



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# File 'lib/k_means/node.rb', line 42

def reset!
  @closest_centroid = nil
  @best_distance    = nil
end

#update_closest_centroid(centroids) ⇒ Object 



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# File 'lib/k_means/node.rb', line 20

def update_closest_centroid(centroids)
  # If we haven't processed this node we need to give it an initial centroid
  # so that we have something to compare distances against
  calculate_initial_centroid(centroids.first) unless @closest_centroid

  updated = false
  centroids.each do |centroid|
    # Check if they are in the same position
    if centroid.position == @position
      updated = update_attributes(centroid, 0.0)
      break
    end

    distance = calculate_distance(centroid)
    if distance < best_distance
      updated = update_attributes(centroid, distance)
    end
  end

  updated == true ? 1 : 0
end