class DbClustering::DistanceMetrics::EuclideanDistance
Public Class Methods
new(min_dimensions: 1)
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# File lib/distance_metrics/euclidean_distance.rb, line 6 def initialize(min_dimensions: 1) @min_dimensions = min_dimensions end
Public Instance Methods
distance(vector1, vector2)
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# File lib/distance_metrics/euclidean_distance.rb, line 10 def distance(vector1, vector2) vector1_array = vector1.array_for_comparison(vector2) vector2_array = vector2.array_for_comparison(vector1) if vector1_array.count != vector2_array.count raise "Vectors with different sizes cannot be compared" end if vector1_array.count < @min_dimensions return Float::INFINITY end # see here for calculation formula: http://en.wikipedia.org/wiki/Euclidean_distance sum = 0 vector1_array.count.times do |i| sum += (vector1_array[i] - vector2_array[i]) ** 2 end sqrt sum end