Homework 1, #6

feasability.rb

#!/usr/bin/env ruby

class Array
  def agreement(other)
    raise ArgumentError, "Cannot compare arrays of different sizes" if size != other.size
    other.each_with_index.map do |elem, i|
      self[i] == elem ? 1 : 0
    end
  end
end

data_set = [
  [1,0,1],
  [1,1,0],
  [1,1,1]
]

target_functions = [
  [0, 0, 0],
  [1, 0, 0],
  [0, 1, 0],
  [0, 0, 1],
  [1, 1, 0],
  [1, 0, 1],
  [0, 1, 1],
  [1, 1, 1]
]

def score
  running_tally = 0
  [3,2,1,0].each do |weight|
    running_tally += (yield weight) * weight
  end
  running_tally
end

def xor(point)
  point.count(1) % 2 == 1 ? 1 : 0
end

def xor_all(points)
  points.map { |point| xor(point) }
end

def nxor(point)
  point.count(1) % 2 == 1 ? 0 : 1
end

def nxor_all(points)
  points.map { |point| nxor(point) }
end

total_a = score do |i|
  target_functions.select { |target_function| target_function.count(1) == i }.size
end

total_b = score do |i|
  target_functions.select { |target_function| target_function.count(0) == i }.size
end

xor_data = xor_all(data_set)
nxor_data = nxor_all(data_set)

total_c = score do |i|
  target_functions.select do |target_function|
    target_function.agreement(xor_data).count(1) == i
  end.size
end

total_d = score do |i|
  target_functions.select do |target_function|
    target_function.agreement(nxor_data).count(1) == i
  end.size
end

puts total_a
puts total_b
puts total_c
puts total_d