+ let () = print_string (error_message) in
+ let result = transpose (Array.sub container 0 !index) in
+ let toc = Sys.time () in
+ let () = print_endline (" Done. (duration: " ^ (string_of_float (toc -. tic)) ^ "s.)") in
+ result
+
+ method frequency : int array =
+ let each_rate : signal -> int =
+ fun (s : signal) ->
+ let rate = s#frequency in
+ if rate > 0 then rate
+ else if rate = 0 then 44100
+ else raise (Beam_matching "frequency error.") in
+ Array.map each_rate self#get
+