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yap-6.3/packages/cplint/approx/tptree_lpad.pl
RIGUZZI FABRIZIO - Dipartimento di Ingegneria b2238c1644 removed debug printf, changed module tptree name
2010-03-21 11:49:19 +01:00

734 lines
18 KiB
Prolog

%%% -*- Mode: Prolog; -*-
:-source.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% prefix-trees for managing a DNF
% remembers shortest prefix of a conjunction only (i.e. a*b+a*b*c results in a*b only, but b*a+a*b*c is not reduced)
% children are sorted, but branches aren't (to speed up search while keeping structure sharing from proof procedure)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
/* derived from tptree.yap from ProbLog by Fabrizio Riguzzi in 2009
for dealing with multivalued variables
instead of variables or their negation, the script can contain equations of the
form
variable=value
*/
:- module(ptree_lpad,[init_ptree/1,
delete_ptree/1,
rename_ptree/2,
member_ptree/2,
enum_member_ptree/2,
insert_ptree/2,
delete_ptree/2,
edges_ptree/2,
count_ptree/2,
prune_check_ptree/2,
empty_ptree/1,
merge_ptree/3,
bdd_ptree/3,
bdd_ptree_map/4
]).
:-source.
:- use_module(library(tries),
[
trie_open/1,
trie_close/1,
trie_stats/4,
trie_check_entry/3,
trie_get_entry/2,
trie_put_entry/3,
trie_remove_entry/1,
trie_usage/4,
trie_dup/2,
trie_join/2,
trie_traverse/2
]).
:- use_module(library(ordsets),
[
ord_subset/2
]).
:- style_check(all).
%:- yap_flag(unknown,error).
%:- use_module(flags,[problog_flag/2]).
:- ensure_loaded(library(lists)).
:- ensure_loaded(library(system)).
% name lexicon external - internal
sym(1,tree1) :- !.
sym(2,tree2) :- !.
sym(3,tree3) :- !.
sym(N,AN) :- atomic_concat([tree,N],AN).
%%%%%%%%%%%%%%%%%%%%%%%%
% ptree basics
%%%%%%%%%%%%%%%%%%%%%%%%
init_ptree(ID) :-
sym(ID,Sym),
trie_open(Trie),
nb_setval(Sym, Trie).
delete_ptree(ID) :-
sym(ID,Sym),
nb_getval(Sym, Trie), !,
trie_close(Trie),
trie_open(NewTrie),
nb_setval(Sym, NewTrie).
delete_ptree(_).
rename_ptree(OldID,NewID) :-
sym(OldID,OldSym),
sym(NewID,NewSym),
nb_getval(OldSym, Trie),
nb_set_shared_val(NewSym, Trie).
empty_ptree(ID) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_usage(Trie, 0, 0, 0).
%%%%%%%%%%%%%%%%%%%%%%%%
% member
%%%%%%%%%%%%%%%%%%%%%%%%
% non-backtrackable (to check)
member_ptree(List,ID) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_check_entry(Trie, List, _).
% backtrackable (to list)
enum_member_ptree(ID,List) :-
sym(ID,Sym),
nb_getval(Sym, Tree),
trie_path(Tree, List).
trie_path(Tree, List) :-
trie_traverse(Tree,Ref),
trie_get_entry(Ref, List).
%%%%%%%%%%%%%%%%%%%%%%%%
% insert conjunction
%%%%%%%%%%%%%%%%%%%%%%%%
insert_ptree(true,ID) :-
sym(ID,Sym),
!,
nb_getval(Sym, Trie),
trie_close(Trie),
trie_open(NTrie),
trie_put_entry(NTrie, true, _).
insert_ptree(List,ID) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_put_entry(Trie, List, _).
%%%%%%%%%%%%%%%%%%%%%%%%
% delete conjunction
%%%%%%%%%%%%%%%%%%%%%%%%
delete_ptree(List,ID) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_check_entry(Trie, List, Ref),
trie_remove_entry(Ref).
%%%%%%%%
% return list -Edges of all edge labels in ptree
% doesn't use any heuristic to order those for the BDD
% (automatic reordering has to do the job)
%%%%%%%%%
edges_ptree(ID,[]) :-
empty_ptree(ID),
!.
edges_ptree(ID,[]) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_check_entry(Trie, true, _),
!.
edges_ptree(ID,Edges) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
%(
setof(X, trie_literal(Trie, X), Edges).%->
/* true
;
Edges=[]
).*/
trie_literal(Trie, X) :-
trie_traverse(Trie,Ref),
trie_get_entry(Ref, List),
member(X, List).
%%%%%%%%
% number of conjunctions in the tree
%%%%%%%%%
count_ptree(ID,N) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_usage(Trie, N, _, _).
%%%%%%%%
% check whether some branch of ptree is a subset of conjunction List
% useful for pruning the search for proofs (optional due to time overhead)
% currently not implemented, just fails
%%%%%%%
prune_check_ptree(_List,_TreeID) :-
format(user,'FAIL: prune check currently not supported~n',[]),
flush_output(user),
fail.
%%%%%%%%%%%%%
% merge two ptrees
% - take care not to loose proper prefixes that are proofs!
%%%%%%%%%%%%%%%
merge_ptree(ID1,_,ID3) :-
sym(ID1,Sym1),
sym(ID3,Sym3),
nb_getval(Sym1, T1),
trie_check_entry(T1, true, _),
!,
trie_open(T3),
trie_put_entry(T3, true, _),
nb_setval(Sym3, T3).
merge_ptree(_,ID2,ID3) :-
sym(ID2,Sym2),
sym(ID3,Sym3),
nb_getval(Sym2, T2),
trie_check_entry(T2, true, _),
!,
trie_open(T3),
trie_put_entry(T3, true, _),
nb_setval(Sym3, T3).
merge_ptree(ID1,ID2,ID3) :-
sym(ID1,Sym1),
sym(ID2,Sym2),
sym(ID3,Sym3),
nb_getval(Sym1, T1),
nb_getval(Sym2, T2),
trie_dup(T1, T3),
trie_join(T3,T2),
nb_setval(Sym3, T3).
%%%%%%%%%%%%%%%%%%%%%%%%
% write BDD info for given ptree to file
% - initializes leaf BDDs (=variables) first
% - then compresses ptree to exploit subtree sharing
% - bdd_pt/1 does the work on the structure itself
%%%%%%%%%%%%%%%%%%%%%%%%
bdd_ptree(ID,FileBDD,FileParam) :-
bdd_ptree_script(ID,FileBDD,FileParam),
eraseall(map),
eraseall(vars).
% version returning variable mapping
bdd_ptree_map(ID,FileBDD,FileParam,FileMapping) :-
bdd_ptree_script(ID,FileBDD,FileParam),
findall(X,recorded(map,X,_),Map),
add_probs(Map,Mapping),
tell(FileMapping),
write(Mapping),write('.'),
told,
eraseall(map),
eraseall(vars).
add_probs([],[]).
add_probs([m(R,S,Num,Name)|Map],[m(R,S,Num,Name,Prob)|Mapping]) :-
user:rule_by_num(R,S,_N,Head,_Body),
user:get_probs(Head,Prob),
add_probs(Map,Mapping).
% number of variables may be to high:
% counted on trie, but conversion to old tree representation
% transforms A*B+A to A (prefix-test)
bdd_ptree_script(ID,FileBDD,FileParam) :-
assert(v_num(0)),
edges_ptree(ID,Edges),
compute_nvars(Edges,0,NVars,0,NBVars),
tell(FileParam),
bdd_vars_script(Edges),
flush_output,
told,
length(Edges,_VarCount),
assert(c_num(1)),
bdd_pt(ID,CT),!,
c_num(NN),
IntermediateSteps is NN-1,
tell(FileBDD),
format('@BDD1~n~w~n~w~n~w~n~w~n',[NVars,NBVars,0,IntermediateSteps]),
output_compressed_script_only(CT),!,
told,
retractall(c_num(_)),
retractall(v_num(_)),
retractall(compression(_,_)).
compute_nvars([],NV,NV,NBV,NBV).
compute_nvars([(_V,R,S)|T],NV0,NV1,NBV0,NBV1):-
(recorded(vars,v(R,S),_)->
compute_nvars(T,NV0,NV1,NBV0,NBV1)
;
recorda(vars,v(R,S),_),
NV2 is NV0+1,
user:rule_by_num(R,S,_N,Head,_Body),
length(Head,L),
NBV2 is NBV0+integer(ceiling(log(L)/log(2))),
compute_nvars(T,NV2,NV1,NBV2,NBV1)
).
% write parameter file by iterating over all var/not(var) occuring in the tree
/*bdd_vars_script(Edges) :-
bdd_vars_script(Edges,0).
*/
bdd_vars_script([]).
%%%% Bernd, changes for negated ground facts
/*
bdd_vars_script([(_V,R,S)|B],N) :-
recorded(map,m(R,S,_Num,_NameA),_),!,
bdd_vars_script(B,N).
*/
bdd_vars_script([(_V,R,S)|B]) :-
(recorded(map,m(R,S,_Number,_NameA),_)->
true
;
user:rule_by_num(R,S,_N,Head,_Body),
user:get_probs(Head,P),
get_var_name(R,S,_Number,NameA),
length(Head,NV),
format('@~w~n~d~n',[NameA,NV]),
print_probs(P)
),
bdd_vars_script(B).
print_probs([H]):-!,
format("~f~n",[H]).
print_probs([H|T]):-
format("~f ",[H]),
print_probs(T).
%%%%%%%%%%%%%%%%%%%%%%%%
% find top level symbol for script
%%%%%%%%%%%%%%%%%%%%%%%%
% special cases: variable-free formulae
bdd_pt(ID,false) :-
empty_ptree(ID),
!,
once(retractall(c_num(_))),
once(assert(c_num(2))).
bdd_pt(ID,true) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_check_entry(Trie, true, _),
!,
once(retractall(c_num(_))),
once(assert(c_num(2))).
% general case: transform trie to nested tree structure for compression
bdd_pt(ID,CT) :-
sym(ID,Sym),
nb_getval(Sym, Trie),
trie_to_tree(Trie, Tree),
compress_pt(Tree,CT).
trie_to_tree(Trie, Tree) :-
findall(Path,trie_path(Trie, Path), Paths),
add_trees(Paths, [], Tree).
add_trees([], Tree, Tree).
add_trees([List|Paths], Tree0, Tree) :-
ins_pt(List, Tree0, TreeI),
add_trees(Paths, TreeI, Tree).
ins_pt([],_T,[]) :- !.
ins_pt([A|B],[s(A1,AT)|OldT],NewT) :-
compare(Comp, A1, A),
(Comp == = ->
(AT == [] ->
NewT=[s(A1,AT)|OldT]
;
NewT = [s(A1,NewAT)|OldT],
ins_pt(B, AT, NewAT))
;
Comp == > ->
NewT = [s(A1,AT)|Tree],
ins_pt([A|B], OldT, Tree)
;
NewT = [s(A,BTree),s(A1,AT)|OldT],
ins_pt(B,[],BTree)
).
ins_pt([A|B],[],[s(A,NewAT)]) :-
ins_pt(B,[],NewAT).
%%%%%%%%%%%%
% BDD compression: alternates and- and or-levels to build BDD bottom-up
% each sub-BDD will be either a conjunction of a one-node BDD with some BDD or a disjunction of BDDs
% uses the internal database to temporarily store a map of components
%%%%%%%%%%%%
% T is completely compressed and contains single variable
% i.e. T of form x12 or ~x34
compress_pt(T,TT) :-
atom(T),
test_var_name(T),
!,
get_next_name(TT),
assertz(compression(TT,[T])).
% T is completely compressed and contains subtrees
% i.e. T of form 'L56'
compress_pt(T,T) :-
atom(T).
% T not yet compressed
% i.e. T is a tree-term (nested list & s/2 structure)
% -> execute one layer of compression, then check again
compress_pt(T,CT) :-
\+ atom(T),
and_or_compression(T,IT),
compress_pt(IT,CT).
% transform tree-term T into tree-term CT where last two layers have been processed
% i.e. introduce names for subparts (-> Map) and replace (all occurrenes of) subparts by this names
and_or_compression(T,CT) :-
and_comp(T,AT),
or_comp(AT,CT).
% replace leaves that are single child by variable representing father-AND-child
and_comp(T,AT) :-
all_leaves_pt(T,Leaves),
compression_mapping(Leaves,Map),
replace_pt(T,Map,AT).
% replace list of siblings by variable representing their disjunction
or_comp(T,AT) :-
all_leaflists_pt(T,Leaves),
compression_mapping(Leaves,Map),
replace_pt(T,Map,AT).
all_leaves_pt(T,L) :-
all(X,some_leaf_pt(T,X),L).
some_leaf_pt([s(A,[])|_],s(A,[])).
some_leaf_pt([s(A,L)|_],s(A,L)) :-
not_or_atom(L).
some_leaf_pt([s(_,L)|_],X) :-
some_leaf_pt(L,X).
some_leaf_pt([_|L],X) :-
some_leaf_pt(L,X).
all_leaflists_pt(L,[L]) :-
atomlist(L),!.
all_leaflists_pt(T,L) :-
all(X,some_leaflist_pt(T,X),L),!.
all_leaflists_pt(_,[]).
some_leaflist_pt([s(_,L)|_],L) :-
atomlist(L).
some_leaflist_pt([s(_,L)|_],X) :-
some_leaflist_pt(L,X).
some_leaflist_pt([_|L],X) :-
some_leaflist_pt(L,X).
not_or_atom(T) :-
(
T=not(T0)
->
atom(T0);
atom(T)
).
atomlist([]).
atomlist([A|B]) :-
not_or_atom(A),
atomlist(B).
% for each subtree that will be compressed, add its name
% only introduce 'L'-based names when subtree composes elements, store these in compression/2 for printing the script
compression_mapping([],[]).
compression_mapping([First|B],[N-First|BB]) :-
(
First = s((V,R,S),[]) % subtree is literal -> use variable's name x17 from map (add ~ for negative case)
->
recorded(map,m(R,S,_Num,Tmp),_), %check
atomic_concat([Tmp,'-',V],N)
;
(First = s(A,L),not_or_atom(L)) % subtree is node with single completely reduced child -> use next 'L'-based name
-> (get_next_name(N),
assertz(compression(N,s(A,L))))
;
(First = [L],not_or_atom(L)) % subtree is an OR with a single completely reduced element -> use element's name
-> N=L
/*,
recorded(refc,m(L,RefC),Ref),
erase(Ref),
RefC1 is RefC+1,
recorda(refc,m(L,RefC1),_)*/
;
(atomlist(First), % subtree is an OR with only (>1) completely reduced elements -> use next 'L'-based name
get_next_name(N),
assertz(compression(N,First)))
),
compression_mapping(B,BB).
increase_counts([]).
increase_counts([H|T]):-
recorded(refc,m(H,RC),Ref),
erase(Ref),
RC1 is RC+1,
recorda(refc,m(H,RC1),_),
increase_counts(T).
compute_or([A],Node0,Node1):-
recorded(mapnodes,m(A,Node),_),
or(Node0,Node,Node1).
compute_or([A,B|T],Node0,Node1):-
recorded(mapnodes,m(A,Node),_),
or(Node0,Node,Node2),
compute_or([B|T],Node2,Node1).
% replace_pt(+T,+Map,-NT)
% given the tree-term T and the Map of Name-Subtree entries, replace each occurence of Subtree in T with Name -> result NT
replace_pt(T,[],T).
replace_pt([],_,[]).
replace_pt(L,M,R) :-
atomlist(L),
member(R-L,M),
!.
replace_pt([L|LL],[M|MM],R) :-
replace_pt_list([L|LL],[M|MM],R).
replace_pt_list([T|Tree],[M|Map],[C|Compr]) :-
replace_pt_single(T,[M|Map],C),
replace_pt_list(Tree,[M|Map],Compr).
replace_pt_list([],_,[]).
replace_pt_single(s(A,T),[M|Map],Res) :-
atomlist(T),
member(Res-s(A,T),[M|Map]),
!.
replace_pt_single(s(A,T),[M|Map],s(A,Res)) :-
atomlist(T),
member(Res-T,[M|Map]),
!.
replace_pt_single(s(A,T),[M|Map],Res) :-
member(Res-s(A,T),[M|Map]),
!.
replace_pt_single(s(A,T),[M|Map],s(A,TT)) :-
replace_pt_list(T,[M|Map],TT).
replace_pt_single(A,_,A) :-
not_or_atom(A).
output_compressed_script_only(false) :-
!,
format('L1 = FALSE~nL1~n',[]).
output_compressed_script_only(true) :-
!,
format('L1 = TRUE~nL1~n',[]).
output_compressed_script_only(T) :-
once(retract(compression(Short,Long))),
assertz(compression(Short,Long)),
(T = Short ->
format('~w = ',[Short]),
format_compression_script_only(Long),
format('~w~n',[Short])
;
format('~w = ',[Short]),
format_compression_script_only(Long),
output_compressed_script_only(T)
).
format_compression_script_only(s((V,R,S),B0)) :-
recorded(map,m(R,S,_Num,C),_),
atomic_concat([C,'-',V],C1),
format('~w * ~w~n',[C1,B0]).
format_compression_script_only([A]) :-
format('~w~n',[A]).
format_compression_script_only([A,B|C]) :-
format('~w + ',[A]),
format_compression_script_only([B|C]).
%%%%%%%%%%%%
% output for script
% input argument is compressed tree, i.e. true/false or name assigned in last compression step
%%%%%%%%%%%%
output_compressed_script(false) :-
!.
%format('L1 = FALSE~nL1~n',[]).
output_compressed_script(true) :-
!.
%format('L1 = TRUE~nL1~n',[]).
% for each name-subtree pair, write corresponding line to script, e.g. L17 = x4 * L16
% stop after writing definition of root (last entry in compression/2), add it's name to mark end of script
output_compressed_script(T) :-
once(retract(compression(Short,Long))),
(T = Short ->
% format('~w = ',[Short]),
format_compression_script(Long,Short)
% format('~w~n',[Short])
;
% format('~w = ',[Short]),
format_compression_script(Long,Short),
output_compressed_script(T)).
format_compression_script(s((V,R,S),B0),Short) :-!,
% checkme
recorded(map,m(R,S,_Num,C),_),
atomic_concat([C,'-',V],C1),
recorded(mapnodes,m(C1,Node1),_),
recorded(mapnodes,m(B0,Node2),_),
% format('~w * ~w~n',[C1,B0]),
and(Node1,Node2,Node),
recorda(mapnodes,m(Short,Node),_),
recorded(refc,m(C1,RefC1),Ref1),
recorded(refc,m(B0,RefC2),Ref2),
erase(Ref1),
erase(Ref2),
RefC11 is RefC1-1,
RefC21 is RefC2-1,
(RefC11 =:=0->
deref(Node1)
;
recorda(refc,m(C1,RefC11),_)
),
(RefC21 =:=0->
deref(Node2)
;
recorda(refc,m(B0,RefC21),_)
).
format_compression_script([H1],Short):-!,
% format('~w~n',[A]),
recorded(mapnodes,m(H1,Node1),_),
recorded(refc,m(H1,RefC1),Ref1),
erase(Ref1),
RefC11 is RefC1-1,
(RefC11 =:=0->
deref(Node1)
;
recorda(refc,m(H1,RefC11),_)
),
recorda(mapnodes,m(Short,Node1),_).
format_compression_script([H1,H2],Short):-!,
% format('~w + ~w~n',[H1,H2]),
recorded(mapnodes,m(H1,Node1),_),
recorded(refc,m(H1,RefC1),Ref1),
erase(Ref1),
RefC11 is RefC1-1,
recorded(mapnodes,m(H2,Node2),_),
recorded(refc,m(H2,RefC2),Ref2),
erase(Ref2),
RefC21 is RefC2-1,
or(Node1,Node2,Node),
(RefC11 =:=0->
deref(Node1)
;
recorda(refc,m(H1,RefC11),_)
),
(RefC21 =:=0->
deref(Node2)
;
recorda(refc,m(H2,RefC21),_)
),
recorda(mapnodes,m(Short,Node),_).
format_compression_script([H1,H2,H3|T],Short):-
%format('~w + ~w +',[H1,H2]),
recorded(mapnodes,m(H1,Node1),_),
recorded(refc,m(H1,RefC1),Ref1),
erase(Ref1),
RefC11 is RefC1-1,
recorded(mapnodes,m(H2,Node2),_),
recorded(refc,m(H2,RefC2),Ref2),
erase(Ref2),
RefC21 is RefC2-1,
or(Node1,Node2,Node),
(RefC11 =:=0->
deref(Node1)
;
recorda(refc,m(H1,RefC11),_)
),
(RefC21 =:=0->
deref(Node2)
;
recorda(refc,m(H2,RefC21),_)
),
format_compression_script1([H3|T],Node,Short).
format_compression_script1([A],Node1,Short) :-!,
% format('~w~n',[A]),
recorded(mapnodes,m(A,Node2),_),
recorded(refc,m(A,RefC),Ref),
erase(Ref),
or(Node1,Node2,Node),
deref(Node1),
recorda(mapnodes,m(Short,Node),_),
RefC1 is RefC-1,
(RefC1=:=0->
deref(Node2)
;
recorda(refc,m(A,RefC1),_)
).
format_compression_script1([A,B|C],Node1,Short) :-
format('~w + ',[A]),
recorded(mapnodes,m(A,Node2),_),
recorded(refc,m(A,RefC),Ref),
erase(Ref),
or(Node1,Node2,Node),
deref(Node1),
RefC1 is RefC-1,
(RefC1=:=0->
deref(Node2)
;
recorda(refc,m(A,RefC1),_)
),
format_compression_script1([B|C],Node,Short).
%%%%%%%%%%%%%%%%%%%%%%%%
% auxiliaries for translation to BDD
%%%%%%%%%%%%%%%%%%%%%%%%
% prefix the current counter with "L"
get_next_name(Name) :-
retract(c_num(N)),
NN is N+1,
assert(c_num(NN)),
atomic_concat('L',N,Name).
get_next_var_id(N,Name) :-
retract(v_num(N)),
NN is N+1,
assert(v_num(NN)),
atomic_concat('x',N,Name).
% create BDD-var as fact id prefixed by x
% learning.yap relies on this format!
% when changing, also adapt test_var_name/1 below
get_var_name(R,S,Number,NameA) :-
get_next_var_id(Number,NameA),
recorda(map,m(R,S,Number,NameA),_).
% test used by base case of compression mapping to detect single-variable tree
% has to match above naming scheme
test_var_name(T) :-
atomic_concat(x,_,T).