Refactoring of Signal class by adding a rate class.

[Faustine.git] / interpretor / signal.ml

diff --git a/interpretor/signal.ml b/interpretor/signal.ml
index b8f0e68..00a1709 100644 (file)
--- a/interpretor/signal.ml
+++ b/interpretor/signal.ml
@@ -13,8 +13,45 @@ exception Signal_operation of string;;
 
 let delay_memory_length = 10000;;
 
-class signal : int -> (time -> value_type) -> signal_type = 
-  fun (freq_init : int) ->
+class rate : int -> int -> rate_type = 
+  fun (num_init : int) ->
+    fun (denom_init : int) ->
+      let rec pgcd : int -> int -> int = 
+       fun i1 -> fun i2 ->
+         let r = i1 mod i2 in 
+         if r = 0 then i2 else pgcd i2 r in
+      let num_positive = 
+       if num_init >= 0 then num_init 
+       else (-num_init) in
+      let denom_positive = 
+       if denom_init > 0 then denom_init 
+       else if denom_init < 0 then -denom_init
+       else raise (Signal_operation "sample rate denominater = 0.") in
+      let factor = pgcd num_positive denom_positive in
+      let num_corrected = num_init / factor in
+      let denom_corrected = denom_init / factor in
+      object (self)
+       val _num = num_corrected
+       val _denom = denom_corrected
+       method num = _num
+       method denom = _denom
+       method to_int = 
+         self#num / self#denom
+       method to_float = 
+         (float_of_int self#num) /. (float_of_int self#denom)
+       method to_string = 
+         (string_of_int self#num) ^ "/" ^ (string_of_int self#denom)
+       method equal : rate_type -> bool = 
+         fun (r : rate_type) -> (self#num = r#num) && (self#denom = r#denom)
+       method mul : int -> rate_type = 
+         fun (i : int) -> new rate (self#num * i) self#denom
+       method div : int -> rate_type = 
+         fun (i : int) -> new rate self#num (self#denom * i)
+      end
+         
+
+class signal : rate_type -> (time -> value_type) -> signal_type = 
+  fun (freq_init : rate_type) ->
     fun (func_init : time -> value_type) ->
       object (self)
        val mutable signal_func = func_init
@@ -22,13 +59,13 @@ class signal : int -> (time -> value_type) -> signal_type =
        method frequency = freq_init
        method at = signal_func
 
-       method private check_freq : signal_type list -> int = 
+       method private check_freq : signal_type list -> rate_type = 
          fun (sl : signal_type list) ->
-           let check : int -> signal_type -> int = 
-             fun (f : int) ->
+           let check : rate_type -> signal_type -> rate_type = 
+             fun (f : rate_type) ->
                fun (s : signal_type) ->
-                 if f = s#frequency || s#frequency = 0 then f
-                 else if f = 0 then s#frequency
+                 if f#equal s#frequency || s#frequency#num = 0 then f
+                 else if f#num = 0 then s#frequency
                  else raise (Signal_operation "frequency not matched.") in
            List.fold_left check self#frequency sl
 
@@ -90,6 +127,8 @@ class signal : int -> (time -> value_type) -> signal_type =
        method _mod = self#prim2 (fun t -> (self#at t)#_mod)
        method larger = self#prim2 (fun t -> (self#at t)#larger)
        method smaller = self#prim2 (fun t -> (self#at t)#smaller)
+       method max = self#prim2 (fun t -> (self#at t)#max)
+       method min = self#prim2 (fun t -> (self#at t)#min)
 
        method delay : signal_type -> signal_type =
          fun (s : signal_type) ->
@@ -98,13 +137,13 @@ class signal : int -> (time -> value_type) -> signal_type =
            let func : time -> value_type = 
              fun (t : time) ->
                let i = (s#at t)#to_int in
-               self#delay_by t i  in
+               self#delay_by i t  in
            new signal freq func
 
        method mem : signal_type = 
          let freq = self#frequency in
          let () = self#add_memory 1 in
-         let func = fun (t : time) -> self#delay_by t 1 in
+         let func = fun (t : time) -> self#delay_by 1 t in
          new signal freq func
 
        method rdtable : signal_type -> signal_type -> signal_type = 
@@ -141,10 +180,11 @@ class signal : int -> (time -> value_type) -> signal_type =
                    
        method prefix : signal_type -> signal_type =
            fun (s_init : signal_type) ->
+             let () = self#add_memory 1 in
              let func : time -> value_type = 
                fun t ->
                  if t = 0 then s_init#at 0
-                 else if t > 0 then self#at t
+                 else if t > 0 then self#at (t - 1) 
                  else raise (Signal_operation "prefix time < 0.") in
              new signal self#frequency func
 
@@ -155,7 +195,7 @@ class signal : int -> (time -> value_type) -> signal_type =
            if size <= 0 then      
              raise (Signal_operation "Vectorize: size <= 0.")
            else 
-             let freq = self#frequency / size in
+             let freq = self#frequency#div size in
              let func : time -> value_type = 
                fun t ->
                  let vec = fun i -> (self#at (size * t + i))#get in
@@ -168,7 +208,7 @@ class signal : int -> (time -> value_type) -> signal_type =
            match (self#at 0)#get with
            | Vec vec -> vec#size
            | _ -> raise (Signal_operation "Serialize: scalar input.") in
-         let freq = self#frequency * size in
+         let freq = self#frequency#mul size in
          let func : time -> value_type = 
            fun t -> 
              match (self#at (t/size))#get with