# File lib/standard/facets/random.rb, line 200 def rand_subset(number=nil, exclusive=true) number = Random.number(size) unless number number = number.to_int #return self.dup if (number >= size and exlusive) return sort_by{rand}.slice(0,number) if exclusive ri =[]; number.times { |n| ri << Random.number(size) } return values_at(*ri) end