X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Fmathql_interpreter%2Fintersect.ml;h=73bebaa507c2300f5bd90dcc4c5001d887744eae;hb=ba824e867afc3eaf081ed1a1d6526d421242a6a0;hp=bf0d05c2c71454dd5aaad0e0be72472741009bc2;hpb=0b2c5757a7d7d87adc0144f790ca5294f9433175;p=helm.git

diff --git a/helm/ocaml/mathql_interpreter/intersect.ml b/helm/ocaml/mathql_interpreter/intersect.ml
index bf0d05c2c..73bebaa50 100644
--- a/helm/ocaml/mathql_interpreter/intersect.ml
+++ b/helm/ocaml/mathql_interpreter/intersect.ml
@@ -23,105 +23,53 @@
  * http://cs.unibo.it/helm/.
  *)
 
-exception NotCompatible;;
 
-(* intersect_attributes is successful iff there is no attribute with *)
-(* two different values in the two lists. The returned list is the   *)
-(* union of the two lists.                                           *)
-let rec intersect_attributes (attr1, attr2) =
- match attr1, attr2 with
-    [],_ -> attr2
-  | _,[] -> attr1
-  | (key1,value1)::tl1, (key2,_)::_ when key1 < key2 ->
-      (key1,value1)::(intersect_attributes (tl1,attr2))
-  | (key1,_)::_, (key2,value2)::tl2 when key2 < key1 ->
-      (key2,value2)::(intersect_attributes (attr1,tl2))
-  | entry1::tl1, entry2::tl2 when entry1 = entry2 ->
-     entry1::(intersect_attributes (tl1,tl2))
-  | _, _ -> raise NotCompatible  (* same keys, different values *)
+(* Catenates two lists preserving order and getting rid of duplicates *)
+let rec append (l1,l2) =
+  match l1,l2 with
+     [],_ -> l2
+   | _,[] -> l1
+   | s1::tl1, s2::_ when s1 < s2 -> s1::append (tl1,l2)                     
+   | s1::_, s2::tl2 when s2 < s1 -> s2::append (l1,tl2) 
+   | s1::tl1, s2::tl2 -> s1::append (tl1,tl2) 
+
+;;
+
+
+(* Sums two attribute groups preserving order *)
+let rec sum_groups(gr1, gr2) =
+  match gr1, gr2 with
+     [],_ -> gr2
+   | _,[] -> gr1
+   | gr1, gr2 when gr1 = gr2 -> gr1
+   | (key1,l1)::tl1, (key2,l2)::_ when key1 < key2 -> (key1,l1)::(sum_groups (tl1,gr2))
+   | (key1,l1)::_, (key2,l2)::tl2 when key2 < key1 -> (key2,l2)::(sum_groups (gr1,tl2))
+   | (key1,l1)::tl1, (key2,l2)::tl2 -> (key1,(append (l1,l2)))::(sum_groups (tl1,tl2))
+
+;;
+
+(* Product between an attribute set and a group of attributes *)
+let rec sub_prod (aset, gr) = (*prende un aset e un gr, fa la somma tra tutti i gruppi di aset e gr*)
+  match aset with
+      [] -> []
+    | gr1::tl1 -> sum_groups (gr1, gr)::(sub_prod(tl1, gr)) 
 ;;
 
-(* preserves order and gets rid of duplicates *)
-let rec intersect_ex l1 l2 =
- let module S = Mathql_semantics in
-  match (l1, l2) with
-     [],_
-   | _,[] -> []
-   | {S.uri = uri1}::tl1,
-     {S.uri = uri2}::_ when uri1 < uri2 -> intersect_ex tl1 l2
-   | {S.uri = uri1}::_,
-     {S.uri = uri2}::tl2 when uri2 < uri1 -> intersect_ex l1 tl2
-   | {S.uri = uri1 ; S.attributes = attributes1}::tl1,
-     {S.uri = uri2 ; S.attributes = attributes2}::tl2 ->
-       try
-        let attributes' = intersect_attributes (attributes1,attributes2) in
-         {S.uri = uri1 ; S.attributes = attributes' ; S.extra = ""}::(intersect_ex tl1 tl2)
-       with
-        NotCompatible ->
-         intersect_ex tl1 tl2
+
+(* Cartesian product between two attribute sets*)
+let rec prod (as1, as2) =
+  match as1, as2 with
+    [],_ -> []   
+  | _,[] -> []   
+  | gr1::tl1, _ -> append((sub_prod (as2, gr1)), (prod (tl1, as2)))  (* chiamo la sub_prod con un el. as1 e as2 *)
 ;;
 
-let intersect_ex l1 l2 =
- (* PRE-CLAUDIO
- (*let _ = print_string ("INTERSECT ")
- and t = Unix.time () in*)
- let result = 
-  match (l1, l2) with
-     ((head1::tail1), (head2::tail2)) ->
-      (match (head1, head2) with
-          ([], _) -> assert false (* gli header non devono mai essere vuoti *)
-       |  (_, []) -> assert false (* devono contenere almeno [retVal] *)
-       |  (_,  _) ->
-           (match (tail1, tail2) with
-               ([], _) -> [["retVal"]] (* se una delle due code e' vuota... *)
-            |  (_, []) -> [["retVal"]] (* ... l'intersezione e' vuota *)
-            |  (_,  _) ->
-                [head2 @
-                 (List.find_all
-     	          (function t -> not (List.mem t head2))
-	          head1
-	         )
-	        ] (* header del risultato finale *)
-	        @
-	        intersect_tails (List.tl head1) tail1 (List.tl head2) tail2
-	        (*
-	        List.fold_left
-                 (fun par1 elem1 -> par1 @
-                  List.map
-	           (fun elem2 ->
-	            [(List.hd elem1)] @
-	            (xres_join_context (List.tl head1) (List.tl elem1)
-	                               (List.tl head2) (List.tl elem2)
-                    )
-	           )
-                   (List.find_all (* *)
-                    (fun elem2 ->    (* trova tutti gli elementi della lista tail2 *)
-	             ((List.hd elem1) = (List.hd elem2)) && (* che stanno in tail1 *)
-	             not ((xres_join_context (List.tl head1) (List.tl elem1)
-		                             (List.tl head2) (List.tl elem2)) = [])
-	             (* e per i quali la xres_join_context non sia vuota *)
-	            )
-                    tail2 (* List.find_all *)
-	           )
-                  )
-                []
-                tail1 (* per ogni elemento di tail1 applica la List.fold_left *)
-	        *)
-           ) (* match *)
-      )
-  | _ -> []
-   in
-    (*let _ = print_endline (string_of_float (Unix.time () -. t)); flush stdout in*)
-    result*)
- let before = Unix.time () in
- let res = intersect_ex l1 l2 in
- let after = Unix.time () in
-  let ll1 = string_of_int (List.length l1) in
-  let ll2 = string_of_int (List.length l2) in
-  let diff = string_of_float (after -. before) in
-  print_endline
-   ("INTERSECT(" ^ ll1 ^ "," ^ ll2 ^ ") = " ^ string_of_int (List.length res) ^
-    ": " ^ diff ^ "s") ;
-  flush stdout ;
-  res
+(* Intersection between two resource sets, preserves order and gets rid of duplicates *)
+let rec intersect_ex rs1 rs2 =
+  match (rs1, rs2) with
+    [],_
+  | _,[] -> []
+  | (uri1,_)::tl1, (uri2,_)::_ when uri1 < uri2 -> intersect_ex tl1 rs2
+  | (uri1,_)::_, (uri2,_)::tl2 when uri2 < uri1 -> intersect_ex rs1 tl2
+  | (uri1,as1)::tl1, (uri2,as2)::tl2 -> (uri1, prod(as1,as2))::intersect_ex tl1 tl2 
 ;;