anchor.diff:  % - XXX What should it do if elements/coordinates are duplicated?
   agglomerative_clustering(_Config) ->
       % crash when radius < 0
  -    ?assertError(function_clause, mathlib:aggloClustering([], -1)),
  +    ?expect_exception(mathlib:aggloClustering([], -1), error, function_clause),
   
       % empty centroid list
       ?equals(mathlib:aggloClustering([], 0), []),
  
positive.code:         {timetrap, {seconds, 30}}
      ].
  
  init_per_suite(Config) -> 
      unittest_helper:init_per_suite(Config),
      Config.
  end_per_suite(Config) -> Config.
  
  %% helper functions
  -spec in(X::any(), List::[any()]) -> boolean().
  
negative.code: 
  -include("unittest.hrl").
  -include("scalaris.hrl").
  
  all() -> [
          euclidian_distance
  