Cluster vectors by their similarity defined by a tolerance vector

vector_cluster.rb

require 'matrix'

tolerance = Vector[5, 5, 5]
elements = [Vector[2, 1, 4], Vector[20, 100, 25], Vector[21, 98, 21], Vector[1, 2, 3]]
clusters = []

while(elements.any?)
  element = elements.pop
  cluster, elements = elements.partition do |elem|
    diff = tolerance - (elem - element).map(&:abs)
    diff.all? { |s| s > 0 }
  end
  clusters << (cluster << element)
end

clusters.each { |cluster| p cluster }
# [Vector[2, 1, 4], Vector[1, 2, 3]]
# [Vector[20, 100, 25], Vector[21, 98, 21]]