anchor.diff:      H3 = histogram:add(7.0, H2),
       H4 = lists:foldl(fun histogram:add/2, H3, Values),
       ?equals(histogram:get_data(H4), [{1.25, 2}, {5.0, 4}, {7.0, 1}]),
  +    ok.
  +
  +add3_identical(_Config) ->
  +    H = histogram:create(10),
  +    Values = [{2.0, 1}, {3.5, 2}, {3.0, 1}, {2.0, 6}, {1.0, 3}],
  +    H2 = lists:foldl(fun({Value, Count}, Histogram) ->
  +                             histogram:add(Value, Count, Histogram)
  +                     end,
  +                     H, Values),
  +    ?equals(histogram:get_data(H2), [{1.0, 3}, {2.0, 7}, {3.0, 1}, {3.5, 2}]),
       ok.
   
   resize(_Config) ->
  
positive.code: -compile(export_all).
  
  all()   -> [
              add,
              add_identical,
              resize,
              insert,
              find_smallest_interval,
  
negative.code: end_per_suite(_Config) ->
      ok.
  
  add2(_Config) ->
      H = histogram:create(10),
      Values = [3.5, 3.0, 2.0, 1.0],
      H2 = lists:foldl(fun histogram:add/2, H, Values),
      ?equals(histogram:get_data(H2), [{1.0,1}, {2.0,1}, {3.0,1}, {3.5,1}]),
      ok.
  
  add3(_Config) ->
      H = histogram:create(10),
      Values = [{3.5, 2}, {3.0, 1}, {2.0, 5}, {1.0, 7}],
      H2 = lists:foldl(fun ({Value, Count}, Histogram) ->
                                histogram:add(Value, Count, Histogram)
                       end, H, Values),
      ?equals(histogram:get_data(H2), [{1.0, 7}, {2.0, 5}, {3.0, 1}, {3.5, 2}]),
      ok.
  
  add2_identical(_Config) ->
      H = histogram:create(3),
      Values = [1.25, 5.0, 5.0],
      H2 = lists:foldl(fun histogram:add/2, H, Values),
  