* 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
;;
projects / helm.git / blobdiff