452 lines
16 KiB
Prolog
452 lines
16 KiB
Prolog
/*==============================================================================
|
|
* LPAD and CP-Logic reasoning suite
|
|
* File best.pl
|
|
* Goal oriented interpreter for LPADs based on SLDNF
|
|
* Copyright (c) 2009, Stefano Bragaglia
|
|
*============================================================================*/
|
|
|
|
:- dynamic rule/4, def_rule/2.
|
|
|
|
/* EXTERNAL FILE
|
|
* -------------
|
|
* The following libraries are required by the program to work fine.
|
|
*/
|
|
:- use_module(library(lists)).
|
|
:- use_module(library(system)).
|
|
:- use_module(library(ugraphs)).
|
|
:- use_module(params).
|
|
:- use_module(tptree_lpad).
|
|
:- use_module(utility).
|
|
|
|
% :- source.
|
|
% :- yap_flag(single_var_warnings, on).
|
|
|
|
|
|
|
|
|
|
|
|
/* SOLVING PREDICATES
|
|
* ------------------
|
|
* The predicates in this section solve any given problem with several class of
|
|
* algorithms.
|
|
*
|
|
* Note: the original predicates (no more need and eligible to be deleted) have
|
|
* been moved to the end of the file.
|
|
*/
|
|
|
|
/* solve(Goals, ProbLow, ProbUp, Count, ResTime, BddTime)
|
|
* ------------------------------------------------------
|
|
* This predicate computes the probability of a given list of goals using an
|
|
* iterative deepening, probability bounded algorithm.
|
|
* It also returns the number of handled BDDs and the CPUTime spent performing
|
|
* resolution and spent handling the BDDs.
|
|
*
|
|
* Note: when their derivation is cut, negative goals are added to the head of
|
|
* the goals' list to be solved during the following iteration.
|
|
*
|
|
* INPUT
|
|
* - GoalsList: given list of goal to work on. It can contains variables: the
|
|
* predicate returns in backtracking all the solutions and their equivalent
|
|
* lower and upper bound probability.
|
|
*
|
|
* OUTPUT
|
|
* - ProbLow: resulting lower bound probability for the given list of goals.
|
|
* - ProbUp: resulting upper bound probability for the given list of goals.
|
|
* - Count: number of BDDs generated by the algorithm.
|
|
* - ResTime: CPU time spent on performing resolution.
|
|
* - BddTime: CPU time spent on handling BDDs.
|
|
*/
|
|
solve(Goals, ProbLow, ProbUp, Count, ResTime, BddTime) :-
|
|
setting(k, K),
|
|
setting(min_error, MinError),
|
|
setting(prob_step, ProbStep),
|
|
|
|
ProbStepLog is log(ProbStep),
|
|
|
|
assert(low(0, 0.0)),
|
|
assert(up(1.0)),
|
|
init_ptree(1),
|
|
|
|
% NB: log(1.0) == 0.0 !!!
|
|
bestfirst([0.0-([], [], Goals)], 0, K, MinError, ProbStepLog, ProbLow, ProbUp, 0, Count, 0, ResTime, 0, BddTime),
|
|
|
|
delete_ptree(1),
|
|
retract(low(_, _)),
|
|
retract(up(_)).
|
|
|
|
|
|
|
|
/* bestfirst(GoalsList, Number, Amount, MinError, ProbStep,
|
|
* LowerProb1, UpperProb1, Count0, Count1, ResTime0, ResTime1, BddTime0, BddTime1)
|
|
* -----------------------------------------------------------------------------
|
|
* This recursive supporting predicate performs resolution for current iteration,
|
|
* handles equivalent BDDs (lower and upper one) and calls itself if the current
|
|
* probability error is still bigger than the given minimum error.
|
|
*
|
|
* INPUT
|
|
* - GoalsList: given list of goal to work on.
|
|
* - FoundList: given list of achieved solutions.
|
|
* - Amount: max number of solution considered by each iteration.
|
|
* - MinError: minimum error (closing condition).
|
|
* - ProbStep: probability step.
|
|
* - Count0: number of BDDs already handled by the algorithm.
|
|
* - ResTime0: cpu time already spent on performing resolution.
|
|
* - BddTime0: cpu time already spent on handling BDDs.
|
|
*
|
|
* OUTPUT
|
|
* - LowerProb1: resulting lower bound probability for the given list of goals.
|
|
* - UpperProb1: resulting upper bound probability for the given list of goals.
|
|
* - Count1: number of BDDs handled.
|
|
* - ResTime1: cpu time spent on performing resolution.
|
|
* - BddTime1: cpu time spent on handling BDDs.
|
|
*/
|
|
bestfirst(GoalsList, Number, Amount, MinError, ProbStep, LowerProb1, UpperProb1, Count0, Count1, ResTime0, ResTime1, BddTime0, BddTime1) :-
|
|
% Resetting the clocks...
|
|
statistics(walltime, [_, _]),
|
|
|
|
% Performing resolution...
|
|
main(GoalsList, Amount, ProbStep, List),
|
|
|
|
% Taking elapsed times...
|
|
statistics(walltime, [_, ElapResTime]),
|
|
ResTime2 is ResTime0 + ElapResTime/1000,
|
|
|
|
% Building and solving equivalent bdds...
|
|
init_ptree(2),
|
|
init_ptree(3),
|
|
separate(List, [], LowerList0, [], UpperList, [], Incomplete),
|
|
insert_list_ptree(LowerList0, 1),
|
|
insert_list_ptree(UpperList, 2),
|
|
merge_ptree(1,2,3),
|
|
|
|
length(LowerList0, DeltaLow),
|
|
Next is Number + DeltaLow,
|
|
eval_lower(Next, ProbLow),
|
|
|
|
length(UpperList, DeltaUp),
|
|
Temp is Next + DeltaUp,
|
|
eval_upper(Temp, ProbUp),
|
|
|
|
delete_ptree(2),
|
|
delete_ptree(3),
|
|
|
|
% Taking elapsed times...
|
|
Count2 is Count0 + 2,
|
|
statistics(walltime, [_, ElapBddTime]),
|
|
BddTime2 is BddTime0 + (ElapBddTime / 1000),
|
|
|
|
% Is the current error lower than the minimum error?
|
|
(ProbUp - ProbLow < MinError ->
|
|
% Setting output parameters' values...
|
|
LowerProb1 = ProbLow,
|
|
UpperProb1 = ProbUp,
|
|
Count1 = Count2,
|
|
ResTime1 = ResTime2,
|
|
BddTime1 = BddTime2;
|
|
|
|
% Keeping on iterating with accumulated values...
|
|
% sufficient without negation:
|
|
% D1 = DB,
|
|
% necessary for negation
|
|
bestfirst(Incomplete, Next, Amount, MinError, ProbStep, LowerProb1, UpperProb1, Count2, Count1, ResTime2, ResTime1, BddTime2, BddTime1)).
|
|
|
|
|
|
|
|
/* main(GoalsList, Amount, ProbStep, Pending)
|
|
* ------------------------------------------------
|
|
* This tail recursive predicate takes the given GoalsList and tries to solve
|
|
* the first given Amount quads with the given ProbStep bound on probability,
|
|
* one at a time. After each resolution step, it merges the new solutions to the
|
|
* current list of solutions so that each time it can consider the most
|
|
* promising solution. It finally returns the list of pending solutions, if any.
|
|
*
|
|
* INPUT
|
|
* - GoalsList: current list of goals to solve.
|
|
* - Amount: current number of goals to solve.
|
|
* - ProbStep: incremental probability step for bound.
|
|
*
|
|
* OUTPUT
|
|
* - Sorted: desired sorted (by non increasing prob) results.
|
|
*/
|
|
main([], _Amount, _Step, []) :- !.
|
|
%% Closing condition: stop if no more goals (pending list is an empty list).
|
|
|
|
main(Pending, Amount, _Step, Pending) :-
|
|
Amount =< 0, !.
|
|
%% Closing condition: stop if reached desired amount (pending list is current list).
|
|
|
|
main([Prob0-(Gnd0, Var0, Goals0)|Tail], Amount, Step, Pending) :-
|
|
%% Note: Current list is surely not empty.
|
|
%% Note: A certain amount is surely still needed.
|
|
Bound is Prob0 + Step,
|
|
findall(Prob1-(Gnd1, Var1, Goals1),
|
|
explore(Bound, Prob0-(Gnd0, Var0, Goals0), Prob1-(Gnd1, Var1, Goals1)),
|
|
List),
|
|
%% Find all the solutions reacheable from the first quad.
|
|
sort(List, Sorted),
|
|
merge(Tail, Sorted, Complete),
|
|
|
|
Needed is Amount - 1,
|
|
%% Count current quad as considered.
|
|
main(Complete, Needed, Step, Pending).
|
|
%% Recursive call: consider next quad (updating pending list).
|
|
%% Note: Complete list is sorted; this assures we always consider best quad.
|
|
|
|
|
|
|
|
/* merge(SortedA, SortedB, Sorted)
|
|
* -------------------------------
|
|
* This tail recursive predicate merges the quads in SortedA and SortedB list by
|
|
* non-increasing values of Prob and returns the desired unique Sorted list.
|
|
* The SortedA and SortedB lists must be sorted.
|
|
*
|
|
* INPUT
|
|
* - SortedA: first sorted list of quads.
|
|
* - SortedB: second sorted list of quads.
|
|
*
|
|
* OUTPUT
|
|
* - Sorted: resulting unique sorted list of quads.
|
|
*/
|
|
merge(Sorted, [], Sorted) :- !.
|
|
%% Closing condition: stop if no more items in first sorted list (current second sorted list is output sorted list).
|
|
|
|
merge([], Sorted, Sorted).
|
|
%% Closing condition: stop if no more items in first sorted list (current second sorted list is output sorted list).
|
|
|
|
merge([ProbA-(GndA, VarA, GoalsA)|TailA], [ProbB-(GndB, VarB, GoalsB)|TailB], [ProbA-(GndA, VarA, GoalsA)|Tail]) :-
|
|
ProbA >= ProbB, !,
|
|
merge(TailA, [ProbB-(GndB, VarB, GoalsB)|TailB], Tail).
|
|
%% Recursive call: use the first quad (merge the rest of the first list with the second one).
|
|
|
|
merge([ProbA-(GndA, VarA, GoalsA)|TailA], [ProbB-(GndB, VarB, GoalsB)|TailB], [ProbB-(GndB, VarB, GoalsB)|Tail]) :-
|
|
% ProbA < ProbB, !,
|
|
merge([ProbA-(GndA, VarA, GoalsA)|TailA], TailB, Tail).
|
|
%% Recursive call: use the second quad (merge the first list with the rest of the second one).
|
|
|
|
|
|
|
|
/* separate(List, Low, Up, Next)
|
|
* ----------------------------------
|
|
* This tail recursive predicate parses the input list and builds the list for
|
|
* the lower bound, the upper bound and the pending goals.
|
|
* The upper bound list contains both the items of the lower bound list and the
|
|
* incomplete ones.
|
|
*
|
|
* INPUT
|
|
* - List: input list.
|
|
*
|
|
* OUTPUT
|
|
* - Low: list for lower bound.
|
|
* - Up: list for upper bound.
|
|
* - Next: list of pending goals.
|
|
*/
|
|
separate(List, Low, Up, Next) :-
|
|
%% Polarization: initial low, up and next lists are empty.
|
|
separate(List, [], Low, [], Up, [], Next).
|
|
|
|
separate([], Low, Low, Up, Up, Next, Next) :- !.
|
|
%% Closing condition: stop if no more results (current lists are now final lists).
|
|
|
|
separate([_Prob-(Gnd0, [], [])|Tail], Low0, [Gnd0|Low1], Up0, [Gnd0|Up1], Next0, Next1) :- !,
|
|
separate(Tail, Low0, Low1, Up0, Up1, Next0, Next1).
|
|
|
|
separate([Prob0-(Gnd0, Var0, Goals)|Tail], Low0, Low1, Up0, [Gnd1|Up1], Next0, [Prob1-(Gnd1, Var1, Goals)|Next1]) :-
|
|
get_groundc(Var0, Gnd2, Var1, 1.0, Prob2),
|
|
append(Gnd0, Gnd2, Gnd1),
|
|
Prob1 is Prob0 + log(Prob2),
|
|
separate(Tail, Low0, Low1, Up0, Up1, Next0, Next1).
|
|
|
|
|
|
|
|
/* explore(ProbBound, Prob0-(Gnd0, Var0, Goals0), Prob1-(Gnd1, Var1, Goals1))
|
|
* --------------------------------------------------------------------------
|
|
* This tail recursive predicate reads current explanation and returns the
|
|
* explanation after the current iteration without dropping below the given
|
|
* probability bound.
|
|
*
|
|
* INPUT
|
|
* - ProbBound: the desired probability bound;
|
|
* - Prob0-(Gnd0, Var0, Goals0): current explanation
|
|
* - Gnd0: list of current ground choices,
|
|
* - Var0: list of current non-ground choices,
|
|
* - Prob0: probability of Gnd0,
|
|
* - Goals0: list of current goals.
|
|
*
|
|
* OUTPUT
|
|
* - Prob1-(Gnd1, Var1, Prob1, Goals1): explanation after current iteration
|
|
* - Gnd1: list of final ground choices,
|
|
* - Var1: list of final non-ground choices,
|
|
* - Prob1: probability of Gnd1,
|
|
* - Goals1: list of final goals.
|
|
*/
|
|
explore(_ProbBound, Prob-(Gnd, Var, []), Prob-(Gnd, Var, [])) :- !.
|
|
%% Closing condition: stop if no more goals (input values are output values).
|
|
|
|
explore(ProbBound, Prob-(Gnd, Var, Goals), Prob-(Gnd, Var, Goals)) :-
|
|
%% Closing condition: stop if bound has been reached (input values are output values).
|
|
Prob =< ProbBound, !.
|
|
|
|
% Negation, builtin
|
|
explore(ProbBound, Prob0-(Gnd0, Var0, [\+ Head|Tail]), Prob1-(Gnd1, Var1, Goals1)) :-
|
|
builtin(Head), !,
|
|
call((\+ Head)),
|
|
explore(ProbBound, Prob0-(Gnd0, Var0, Tail), Prob1-(Gnd1, Var1, Goals1)).
|
|
%% Recursive call: consider next goal (building next values)
|
|
|
|
% Negation
|
|
explore(ProbBound, Prob0-(Gnd0, Var0, [\+ Head|Tail]), Prob1-(Gnd1, Var1, Goals1)) :- !,
|
|
list2and(HeadList, Head), % ...
|
|
findall(Prob-(Gnd, Var, CurrentGoals), explore(ProbBound, 0.0-([], [], HeadList), Prob-(Gnd, Var, CurrentGoals)), List) ->
|
|
separate(List, [], LowerBound, [], _UpperBound, [], PendingGoals),
|
|
(PendingGoals \= [] ->
|
|
Var2 = Var0,
|
|
Gnd2 = Gnd0,
|
|
Goals1 = [\+ Head|Goals],
|
|
explore(ProbBound, Prob0-(Gnd2, Var2, Tail), Prob1-(Gnd1, Var1, Goals));
|
|
%% Recursive call: consider next goal (building next values)
|
|
|
|
choose_clausesc(Gnd0, Var0, LowerBound, Var),
|
|
get_groundc(Var, Gnd, Var2, 1, Prob),
|
|
append(Gnd0, Gnd, Gnd2),
|
|
Prob2 is Prob0 + log(Prob),
|
|
explore(ProbBound, Prob2-(Gnd2, Var2, Tail), Prob1-(Gnd1, Var1, Goals1))).
|
|
%% Recursive call: consider next goal (building next values)
|
|
|
|
% Main, builtin
|
|
explore(ProbBound, Prob0-(Gnd0, Var0, [Head|Tail]), Prob1-(Gnd1, Var1, Goals1)) :-
|
|
builtin(Head), !,
|
|
call(Head),
|
|
get_groundc(Var0, Gnd, Var2, 1, Prob),
|
|
append(Gnd0, Gnd, Gnd2),
|
|
Prob2 is Prob0 + log(Prob),
|
|
explore(ProbBound, Prob2-(Gnd2, Var2, Tail), Prob1-(Gnd1, Var1, Goals1)).
|
|
% Recursive call: consider next goal (building next values)
|
|
|
|
% Main, def_rule
|
|
explore(ProbBound, Prob0-(Gnd0, Var0, [Head|Tail]), Prob1-(Gnd1, Var1, Goals1)) :-
|
|
def_rule(Head, Goals0),
|
|
append(Goals0, Tail, Goals2),
|
|
get_groundc(Var0, Gnd, Var2, 1, Prob),
|
|
append(Gnd0, Gnd, Gnd2),
|
|
Prob2 is Prob0 + log(Prob),
|
|
explore(ProbBound, Prob2-(Gnd2, Var2, Goals2), Prob1-(Gnd1, Var1, Goals1)).
|
|
% Recursive call: consider next goal (building next values)
|
|
|
|
% Main, find_rulec
|
|
explore(ProbBound, Prob0-(Gnd0, Var0, [Head|Tail]), Prob1-(Gnd1, Var1, Goals1)) :-
|
|
find_rulec(Head, (R, S, N), Goals, Var0, _Prob),
|
|
explore_pres(ProbBound, R, S, N, Goals, Prob0-(Gnd0, Var0, Tail), Prob1-(Gnd1, Var1, Goals1)).
|
|
|
|
explore_pres(ProbBound, R, S, N, Goals, Prob0-(Gnd0, Var0, Goals0), Prob1-(Gnd1, Var1, Goals)) :-
|
|
(member_eq((N, R, S), Var0);
|
|
member_eq((N, R, S), Gnd0)), !,
|
|
append(Goals, Goals0, Goals2),
|
|
get_groundc(Var0, Gnd, Var2, 1, Prob),
|
|
append(Gnd0, Gnd, Gnd2),
|
|
Prob2 is Prob0 + log(Prob),
|
|
explore(ProbBound, Prob2-(Gnd2, Var2, Goals2), Prob1-(Gnd1, Var1, Goals)).
|
|
% Recursive call: consider next goal (building next values)
|
|
|
|
explore_pres(ProbBound, R, S, N, Goals, Prob0-(Gnd0, Var0, Goals0), Prob1-(Gnd1, Var1, Goals1)) :-
|
|
append(Var0, [(N, R, S)], Var),
|
|
append(Goals, Goals0, Goals2),
|
|
get_groundc(Var, Gnd, Var2, 1, Prob),
|
|
append(Gnd0, Gnd, Gnd2),
|
|
Prob2 is Prob0 + log(Prob),
|
|
explore(ProbBound, Prob2-(Gnd2, Var2, Goals2), Prob1-(Gnd1, Var1, Goals1)).
|
|
% Recursive call: consider next goal (building next values)
|
|
|
|
|
|
|
|
/* eval_lower(Number, Prob)
|
|
* ------------------------
|
|
* This predicate evaluates if there are proofs for the lower bound by
|
|
* running an external command (BDD resolution via files).
|
|
*/
|
|
eval_lower(Number, Prob) :-
|
|
low(Number, Prob).
|
|
|
|
eval_lower(Number, ProbLow) :-
|
|
Number > 0,
|
|
low(OldNumber, _),
|
|
Number \= OldNumber,
|
|
bdd_ptree_map(1, 'bddl.txt', 'bddl.par', 'bddl.map'),
|
|
run_file('bddl.txt', 'bddl.par', NewProbLow),
|
|
(NewProbLow = timeout ->
|
|
low(_, ProbLow);
|
|
|
|
ProbLow = NewProbLow,
|
|
retract(low(_, _)),
|
|
assert(low(Number, ProbLow))).
|
|
|
|
|
|
|
|
/* eval_upper(Number, Prob)
|
|
* ------------------------
|
|
* This predicate evaluates if there are proofs for the upper bound by
|
|
* running an external command (BDD resolution via files).
|
|
*/
|
|
eval_upper(0, ProbUp) :- !,
|
|
low(_, ProbUp).
|
|
|
|
eval_upper(_Number, ProbUp) :-
|
|
bdd_ptree_map(3, 'bddu.txt', 'bddu.par', 'bddu.map'),
|
|
run_file('bddu.txt', 'bddu.par', NewProbUp),
|
|
(NewProbUp = timeout->
|
|
up(ProbUp);
|
|
ProbUp = NewProbUp,
|
|
retract(up(_)),
|
|
assert(up(ProbUp))).
|
|
|
|
|
|
|
|
/* run_file(BDDFile, BDDParFile, Prob)
|
|
* -----------------------------------
|
|
* This predicate calls for the resolution of a BDD via file.
|
|
*/
|
|
run_file(BDDFile, BDDParFile, Prob) :-
|
|
ResultFile = 'result.txt',
|
|
library_directory(Dir),
|
|
setting(timeout, BDDTime),
|
|
(BDDTime = no ->
|
|
atomic_concat([Dir, '/LPADBDD -l ', BDDFile, ' -i ', BDDParFile,' > ', ResultFile], Command);
|
|
atomic_concat([Dir, '/LPADBDD -l ', BDDFile, ' -i ', BDDParFile,' -t ', BDDTime,' > ', ResultFile], Command)),
|
|
|
|
%statistics(walltime,_),
|
|
|
|
shell(Command, Return),
|
|
(Return =\= 0 ->
|
|
Status = timeout,
|
|
Prob = Status;
|
|
|
|
see(ResultFile),
|
|
read(elapsed_construction(_TimeConstruction)),
|
|
read(probability(Prob)),
|
|
read(elapsed_traversing(_TimeTraversing)),
|
|
seen,
|
|
|
|
%write(probability(Prob)),nl,
|
|
%read(_),
|
|
%delete_file(ResultFile),
|
|
|
|
Status = ok
|
|
% format("Construction time ~f traversing time ~f~Number",[TimeConstruction, TimeTraversing])
|
|
).
|
|
|
|
%statistics(walltime,[_,E3]),
|
|
%format(user,'~w ms BDD processing~Number',[E3]),
|
|
% format("Status ~a~Number",[Status]).
|
|
|
|
|
|
|
|
/* insert_list_ptree([Head|Tail], Trie)
|
|
* ------------------------------------
|
|
* This predicate inserts the given list in a trie.
|
|
*/
|
|
insert_list_ptree([], _Trie).
|
|
|
|
insert_list_ptree([Head|Tail], Trie) :-
|
|
reverse(Head, Head1),
|
|
insert_ptree(Head1, Trie),
|
|
insert_list_ptree(Tail, Trie).
|