Do not evaluate the entropy when only 2 words are still presents

3 files changed, 61 insertions, 43 deletions

diff --git a/motus/bin/motus.ml b/motus/bin/motus.ml
index 638e778..823a01b 100644
--- a/motus/bin/motus.ml
+++ b/motus/bin/motus.ml
@@ -69,14 +69,20 @@ let create_new_rules word result =
   !rules
 
 
-let rec run len filters words =
+type t =
+  { catalog : Wordlist.t
+  ; words : Wordlist.t
+  }
+
+let rec run : int -> Criteria.t list -> t -> unit =
+ fun len filters { catalog; words } ->
   let () = show_structure Format.std_formatter words filters in
   (*
   let next =
     Freq_analysis.analyse words |> Freq_analysis.pick_next_word words
   in
   *)
-  let _, next = Entropy.analyse len ~catalog:words words in
+  let _, next = Entropy.analyse len ~catalog words in
 
   let () =
     Format.fprintf Format.std_formatter "Next word will be : %s@\n" next
@@ -86,14 +92,20 @@ let rec run len filters words =
 
   (* if the input is empty, remove the word from the list and restart *)
   match String.equal String.empty input with
-  | true -> run len filters (Wordlist.remove_word words next)
+  | true ->
+      let new_list =
+        { catalog = Wordlist.remove_word catalog next
+        ; words = Wordlist.remove_word words next
+        }
+      in
+      run len filters new_list
   | false ->
       let new_rules =
         Criteria.merge_lists ~init:filters (create_new_rules next input)
         |> List.sort_uniq Stdlib.compare
       in
       let words = Wordlist.filter new_rules words in
-      run len new_rules words
+      run len new_rules { catalog = Wordlist.remove_word catalog next; words }
 
 
 let init_rule rules word =
@@ -122,4 +134,4 @@ let () =
   let words_channel = open_in (List.hd !dict) in
   let words = get_list words_channel initial_filter in
   close_in words_channel;
-  run !length initial_filter words
+  run !length initial_filter { catalog = words; words }
diff --git a/motus/js/initialize.ml b/motus/js/initialize.ml
index 9375880..b721343 100644
--- a/motus/js/initialize.ml
+++ b/motus/js/initialize.ml
@@ -28,14 +28,9 @@ let get_proposition :
     let elements = Wordlist.list_size wordlist in
     if elements > 2000
     then Freq_analysis.analyse wordlist |> Freq_analysis.pick_next_word wordlist
-    else if elements > 1
-    then
+    else
       let _, word = Entropy.analyse length ~catalog wordlist in
       word
-    else
-      match Wordlist.pick wordlist with
-      | Some w -> w
-      | None -> ""
   in
   match String.equal String.empty word with
   | true -> None
diff --git a/motus/lib/entropy.ml b/motus/lib/entropy.ml
index 043d0c8..aec5d86 100644
--- a/motus/lib/entropy.ml
+++ b/motus/lib/entropy.ml
@@ -43,41 +43,52 @@ let get_entropy max_element words_number arr =
 
 let analyse : int -> catalog:Wordlist.t -> Wordlist.t -> t =
  fun base ~catalog words ->
-  let max_element = Float.to_int @@ (Validity.elements ** Float.of_int base) in
-  let words_number = Float.of_int (Wordlist.list_size catalog) in
+  (* If we have only two elements, just pick one of them *)
+  if Wordlist.list_size words <= 2
+  then (1.0, Option.get @@ Wordlist.pick words)
+  else
+    let max_element =
+      Float.to_int @@ (Validity.elements ** Float.of_int base)
+    in
+    let words_number = Float.of_int (Wordlist.list_size catalog) in
 
-  let arr = Bigarray.Array1.create Bigarray.Int Bigarray.C_layout max_element in
-  match Wordlist.pick words with
-  | None -> (0., "")
-  | Some v ->
-      (* Build the array  *)
-      Seq.fold_left
-        (fun (score, word) word_ref ->
-          (* Reinitialize the array (we use the same in the successive
-             iterations *)
-          let set_ref = String.to_seq word_ref |> CharSet.of_seq in
+    let arr =
+      Bigarray.Array1.create Bigarray.Int Bigarray.C_layout max_element
+    in
+    match Wordlist.pick words with
+    | None -> (0., "")
+    | Some v ->
+        (* Build the array  *)
+        Seq.fold_left
+          (fun (score, word) word_ref ->
+            (* Reinitialize the array (we use the same in the successive
+               iterations *)
+            let set_ref = String.to_seq word_ref |> CharSet.of_seq in
 
-          Bigarray.Array1.fill arr 0;
+            Bigarray.Array1.fill arr 0;
 
-          Seq.iter
-            (fun w2 ->
-              let result = compare_words ~ref:(word_ref, set_ref) w2 in
-              match result with
-              | None -> ()
-              | Some r ->
-                  let idx = Validity.index_of_result r in
+            Seq.iter
+              (fun w2 ->
+                let result = compare_words ~ref:(word_ref, set_ref) w2 in
+                match result with
+                | None -> ()
+                | Some r ->
+                    let idx = Validity.index_of_result r in
 
-                  let content = Bigarray.Array1.get arr idx in
-                  Bigarray.Array1.set arr idx (succ content) )
-            (Wordlist.words words);
+                    let content = Bigarray.Array1.get arr idx in
+                    Bigarray.Array1.set arr idx (succ content) )
+              (Wordlist.words words);
 
-          (* Now evaluate the entropy in the array *)
-          let entropy = get_entropy max_element words_number arr in
+            (* Now evaluate the entropy in the array *)
+            let entropy = get_entropy max_element words_number arr in
 
-          if !entropy > score
-          then (
-            Printf.printf "Entropy for selecting %s : %.2f\n" word_ref !entropy;
-            (!entropy, word_ref) )
-          else (score, word) )
-        (-0., v)
-        (Wordlist.words catalog)
+            if !entropy > score
+            then (
+              Printf.printf
+                "Entropy for selecting %s : %.2f\n"
+                word_ref
+                !entropy;
+              (!entropy, word_ref) )
+            else (score, word) )
+          (-0., v)
+          (Wordlist.words catalog)