Sorting a Hash by Key or Value
# ==> Sorting a Hash by Key or Value (see lower) my_hash = {'a'=>'1', 'c'=>'3', 'b'=>'2'} my_hash.keys.sort.each do |key| puts my_hash[key] end Gives: 1 2 3 # Hashes are unsorted objects because of the way in which they are stored #internally. If you want to access a Hash in a sorted manner by key, # you need to use an Array as an indexing mechanism as is shown above. # You can also use the Hash#sort method to get a # ==> new sorted Array of pairs: my_hash.sort #=> [["a", "1"], ["b", "2"], ["c", "3"]] # You can do the same by value, but it’s a little more complicated: my_hash.keys.sort_by { |key| my_hash[key] }.each do |key| puts my_hash[key] end # Or, you can use the Hash#sort method for values: my_hash.sort { |l, r| l[1]<=>r[1] } #=> [["a", "1"], ["b", "2"], ["c", "3"]] # This works by using the Emmuerator#sort_by method that is mixed # into the Array of keys. #sort_by looks at the value my_hash[key] returns # to determine the sorting order.
