type nums = [`Int | `Float]
let random_array =
  let did_init = ref false in
  if not !did_init then (Random.self_init (); did_init := true);
  fun n (num_t : nums) ->
  match num_t with
  | `Int -> Array.init n (fun _ -> Random.int max_int)
  | `Float -> Array.init n (fun _ -> Random.float max_float)