Counting sub-sequence patterns in an array of unique numbers

example_out.txt

Patterns in [10, 1, 3, 2, 8, 9, 5, 4, 6, 7]:
[10, 1, 3] => 312
[10, 1, 2] => 312
[10, 1, 8] => 312
[10, 1, 9] => 312
[10, 1, 5] => 312
[10, 1, 4] => 312
[10, 1, 6] => 312
[10, 1, 7] => 312
[10, 3, 2] => 321
[10, 3, 8] => 312
[10, 3, 9] => 312
[10, 3, 5] => 312
[10, 3, 4] => 312
[10, 3, 6] => 312
[10, 3, 7] => 312
[10, 2, 8] => 312
[10, 2, 9] => 312
[10, 2, 5] => 312
[10, 2, 4] => 312
[10, 2, 6] => 312
[10, 2, 7] => 312
[10, 8, 9] => 312
[10, 8, 5] => 321
[10, 8, 4] => 321
[10, 8, 6] => 321
[10, 8, 7] => 321
[10, 9, 5] => 321
[10, 9, 4] => 321
[10, 9, 6] => 321
[10, 9, 7] => 321
[10, 5, 4] => 321
[10, 5, 6] => 312
[10, 5, 7] => 312
[10, 4, 6] => 312
[10, 4, 7] => 312
[10, 6, 7] => 312
[1, 3, 2] => 132
[1, 3, 8] => 123
[1, 3, 9] => 123
[1, 3, 5] => 123
[1, 3, 4] => 123
[1, 3, 6] => 123
[1, 3, 7] => 123
[1, 2, 8] => 123
[1, 2, 9] => 123
[1, 2, 5] => 123
[1, 2, 4] => 123
[1, 2, 6] => 123
[1, 2, 7] => 123
[1, 8, 9] => 123
[1, 8, 5] => 132
[1, 8, 4] => 132
[1, 8, 6] => 132
[1, 8, 7] => 132
[1, 9, 5] => 132
[1, 9, 4] => 132
[1, 9, 6] => 132
[1, 9, 7] => 132
[1, 5, 4] => 132
[1, 5, 6] => 123
[1, 5, 7] => 123
[1, 4, 6] => 123
[1, 4, 7] => 123
[1, 6, 7] => 123
[3, 2, 8] => 213
[3, 2, 9] => 213
[3, 2, 5] => 213
[3, 2, 4] => 213
[3, 2, 6] => 213
[3, 2, 7] => 213
[3, 8, 9] => 123
[3, 8, 5] => 132
[3, 8, 4] => 132
[3, 8, 6] => 132
[3, 8, 7] => 132
[3, 9, 5] => 132
[3, 9, 4] => 132
[3, 9, 6] => 132
[3, 9, 7] => 132
[3, 5, 4] => 132
[3, 5, 6] => 123
[3, 5, 7] => 123
[3, 4, 6] => 123
[3, 4, 7] => 123
[3, 6, 7] => 123
[2, 8, 9] => 123
[2, 8, 5] => 132
[2, 8, 4] => 132
[2, 8, 6] => 132
[2, 8, 7] => 132
[2, 9, 5] => 132
[2, 9, 4] => 132
[2, 9, 6] => 132
[2, 9, 7] => 132
[2, 5, 4] => 132
[2, 5, 6] => 123
[2, 5, 7] => 123
[2, 4, 6] => 123
[2, 4, 7] => 123
[2, 6, 7] => 123
[8, 9, 5] => 231
[8, 9, 4] => 231
[8, 9, 6] => 231
[8, 9, 7] => 231
[8, 5, 4] => 321
[8, 5, 6] => 312
[8, 5, 7] => 312
[8, 4, 6] => 312
[8, 4, 7] => 312
[8, 6, 7] => 312
[9, 5, 4] => 321
[9, 5, 6] => 312
[9, 5, 7] => 312
[9, 4, 6] => 312
[9, 4, 7] => 312
[9, 6, 7] => 312
[5, 4, 6] => 213
[5, 4, 7] => 213
[5, 6, 7] => 123
[4, 6, 7] => 123
{"123"=>32, "132"=>28, "213"=>8, "231"=>4, "312"=>36, "321"=>12}

report_counts.rb

# build a table of pattern recognizers based on < relations between all elements of an array

def less_than_vector(numbers)
  numbers.combination(2).collect {|pair| (pair[0]<pair[1])}
end

@pattern_length = 3

def pattern_dictionary(length)
  lookups = (1..length).to_a.permutation().inject([]) do |array,pattern|
    key = pattern.join
    value = less_than_vector(pattern)
    array << value << key
  end
  Hash[*lookups]
end

# puts pattern_dictionary(3).inspect

# convert a sequence into a collection of sub-sequences

@sequence = (1..10).to_a.shuffle

puts "Patterns in #{@sequence.inspect}:"

def count_every_pattern(numbers,size)
  matcher = pattern_dictionary(size)
  counts = Hash.new(0)
  (0...numbers.length).to_a.combination(size) do |indices|
    subsequence = indices.collect{|idx| numbers[idx]}
    puts "#{subsequence.inspect} => #{matcher[less_than_vector(subsequence)]}"
    counts[matcher[less_than_vector(subsequence)]] += 1
  end
  return Hash[counts.sort]
end

puts count_every_pattern(@sequence,3)