(** Module: Beam Description: beam definition and operations @author WANG Haisheng Created: 21/07/2013 Modified: 21/07/2013 *) exception Beam_matching of string;; open Types;; open Basic;; open Value;; open Signal;; class beam : signal_type array -> beam_type = fun (signals_init : signal_type array) -> object (self) val signals = signals_init method get = signals method width = Array.length signals method sub : int -> int -> beam_type = fun start -> fun len -> new beam (Array.sub self#get start len) method cut : int -> beam_type * beam_type = fun (cut_width : int)-> ((self#sub 0 cut_width),(self#sub cut_width (self#width - cut_width))) method append : beam_type -> beam_type = fun (b : beam_type) -> new beam (Array.append self#get b#get) method private add_memory : int -> unit = fun (window : int) -> let signal_add_memory : int -> signal_type -> unit = fun (l : int) -> fun (s : signal) -> s#add_memory l in let _ = Array.map (signal_add_memory window) self#get in () method matching : int -> beam_type = fun size -> if size = self#width then new beam self#get else if (size > self#width) && (size mod self#width = 0) then let () = self#add_memory 1 in let split_signals = Array.concat (Array.to_list (Array.make (size/self#width) self#get)) in new beam split_signals else if (size < self#width) && (self#width mod size = 0) then let rec merge_rec = fun (sa : signal_type array) -> fun (l : int) -> fun (i : int) -> if i + l < Array.length sa then (sa.(i))#add (merge_rec sa l (i + l)) else sa.(i) in let merge_signals = Array.init size (merge_rec self#get size) in new beam merge_signals else raise (Beam_matching "matching size error") method at : time -> value_type array = fun t -> let signal_at = fun (t : time) -> fun (s : signal_type) -> s#at t in Array.map (signal_at t) self#get method output : int -> data = fun (length_max : int) -> let transpose : 'a array array -> 'a array array = fun matrix -> let get_element = fun i -> fun array -> array.(i) in let get_column = fun m -> fun i -> Array.map (get_element i) m in Array.init self#width (get_column matrix) in let value2float = fun (v : value_type) -> v#to_float_array in let init = [|0.|] in let container = Array.make length_max (Array.make self#width init) in let index = ref 0 in try while !index < length_max do container.(!index) <- Array.map value2float (self#at !index); incr index; done; transpose container with x -> match x with | Invalid_argument s -> transpose (Array.sub container 0 !index) | _ -> raise x method frequency : rate_type array = let each_rate : signal -> rate = fun (s : signal) -> let rate = s#frequency in if rate#num > 0 then rate else if rate#num = 0 then new rate 44100 1 else raise (Beam_matching "frequency error.") in Array.map each_rate self#get end