liquidity.rb

require 'enumerator'

class Array

  def column_sort(num_columns, &block)
    new_array = block ? sort(&block) : self.dup
    extras = new_array.length % num_columns
    new_length = extras == 0 ? new_array.length : new_array.length + num_columns - extras
    new_array.pad(new_length).slices(num_columns).transpose.flatten
  end
  
  def pad(new_length)
    if new_length > length
      self + ([nil] * (new_length - length))
    else
      self.dup
    end
  end
  
  def slices(num_slices)
    array_of_slices = []
    each_slice(length / num_slices) { |s| array_of_slices << s }
    array_of_slices
  end

end