/usr/share/Yap/clpbn/connected.yap is in yap 6.2.2-6.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 | :- module(clpbn_connected,
[clpbn_subgraphs/2,
influences/4,
init_influences/3,
influences/5]).
:- use_module(library(dgraphs),
[dgraph_new/1,
dgraph_add_edges/3,
dgraph_add_vertex/3,
dgraph_neighbors/3,
dgraph_edge/3]).
:- use_module(library(rbtrees),
[rb_new/1,
rb_insert/4,
rb_lookup/3]).
:- attribute component/1.
% search for connected components, that is, where we know that A influences B or B influences A.
clpbn_subgraphs(Vs, Gs) :-
mark_components(Vs, Components),
keysort(Components, Ordered),
same_key(Ordered, Gs).
% ignore variables with evidence,
% the others mark the MB.
mark_components([], []).
mark_components([V|Vs], Components) :-
clpbn:get_atts(V, [evidence(_),dist(_,Parents)]), !,
merge_parents(Parents, _),
mark_components(Vs, Components).
mark_components([V|Vs], [Mark-V|Components]) :-
mark_var(V, Mark),
mark_components(Vs, Components).
mark_var(V, Mark) :-
get_atts(V, [component(Mark)]), !,
clpbn:get_atts(V, [dist(_,Parents)]), !,
merge_parents(Parents, Mark).
mark_var(V, Mark) :-
clpbn:get_atts(V, [dist(_,Parents)]), !,
put_atts(V,[component(Mark)]),
merge_parents(Parents, Mark).
merge_parents([], _).
merge_parents([V|Parents], Mark) :-
clpbn:get_atts(V,[evidence(_)]), !,
merge_parents(Parents, Mark).
merge_parents([V|Parents], Mark) :-
get_atts(V,[component(Mark)]), !,
merge_parents(Parents, Mark).
merge_parents([V|Parents], Mark) :-
put_atts(V,[component(Mark)]),
merge_parents(Parents, Mark).
same_key([],[]).
same_key([K-El|More],[[El|Els]|Gs]) :-
same_keys(More, K, Els, Rest),
same_key(Rest,Gs).
same_keys([], _, [], []).
same_keys([K1-El|More], K, [El|Els], Rest) :-
K == K1, !,
same_keys(More, K, Els, Rest).
same_keys(Rest, _, [], Rest).
influences_more([], _, _, Is, Is, Evs, Evs, V2, V2).
influences_more([V|LV], G, RG, Is0, Is, Evs0, Evs, GV0, GV2) :-
rb_lookup(V, _, GV0), !,
influences_more(LV, G, RG, Is0, Is, Evs0, Evs, GV0, GV2).
influences_more([V|LV], G, RG, Is0, Is, Evs0, Evs, GV0, GV3) :-
rb_insert(GV0, V, _, GV1),
follow_dgraph(V, G, RG, [V|Is0], Is1, [V|Evs0], Evs1, GV1, GV2),
influences_more(LV, G, RG, Is1, Is, Evs1, Evs, GV2, GV3).
% search for the set of variables that influence V
influences(Vs, LV, Is, Evs) :-
init_influences(Vs, G, RG),
influences(LV, Is, Evs, G, RG).
init_influences(Vs, G, RG) :-
dgraph_new(G0),
dgraph_new(RG0),
to_dgraph(Vs, G0, G, RG0, RG).
influences([], [], [], _, _).
influences([V|LV], Is, Evs, G, RG) :-
rb_new(V0),
rb_insert(V0, V, _, V1),
follow_dgraph(V, G, RG, [V], Is1, [V], Evs1, V1, V2),
influences_more(LV, G, RG, Is1, Is, Evs1, Evs, V2, _).
to_dgraph([], G, G, RG, RG).
to_dgraph([V|Vs], G0, G, RG0, RG) :-
clpbn:get_atts(V, [evidence(_),dist(_,Parents)]), !,
build_edges(Parents, V, Edges, REdges),
dgraph_add_edges(G0,[V-e|Edges],G1),
dgraph_add_edges(RG0,REdges,RG1),
to_dgraph(Vs, G1, G, RG1, RG).
to_dgraph([V|Vs], G0, G, RG0, RG) :-
clpbn:get_atts(V, [dist(_,Parents)]),
build_edges(Parents, V, Edges, REdges),
dgraph_add_vertex(G0,V,G1),
dgraph_add_edges(G1, Edges, G2),
dgraph_add_vertex(RG0,V,RG1),
dgraph_add_edges(RG1, REdges, RG2),
to_dgraph(Vs, G2, G, RG2, RG).
build_edges([], _, [], []).
build_edges([P|Parents], V, [P-V|Edges], [V-P|REdges]) :-
build_edges(Parents, V, Edges, REdges).
follow_dgraph(V, G, RG, Is0, IsF, Evs0, EvsF, Visited0, Visited) :-
dgraph_neighbors(V, RG, Parents),
add_parents(Parents, G, RG, Is0, IsI, Evs0, EvsI, Visited0, Visited1),
dgraph_neighbors(V, G, Kids),
add_kids(Kids, G, RG, IsI, IsF, EvsI, EvsF, Visited1, Visited).
add_parents([], _, _, Is, Is, Evs, Evs, Visited, Visited).
% been here already, can safely ignore.
add_parents([V|Vs], G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF) :-
rb_lookup(V, _, Visited0), !,
add_parents(Vs, G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF).
% evidence node,
% just say that we visited it
add_parents([V|Vs], G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF) :-
dgraph_edge(V,e,G), !, % has evidence
rb_insert(Visited0, V, _, VisitedI),
add_parents(Vs, G, RG, Is0, IsF, [V|Evs0], EvsF, VisitedI, VisitedF).
% non-evidence node,
% we will need to find its parents.
add_parents([V|Vs], G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF) :-
rb_insert(Visited0, V, _, VisitedI),
follow_dgraph(V, G, RG, [V|Is0], IsI, [V|Evs0], EvsI, VisitedI, VisitedII),
add_parents(Vs, G, RG, IsI, IsF, EvsI, EvsF, VisitedII, VisitedF).
add_kids([], _, _, Is, Is, Evs, Evs, Visited, Visited).
add_kids([V|Vs], G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF) :-
dgraph_edge(V,e,G), % has evidence
% we will go there even if it was visited
( rb_insert(Visited0, V, _, Visited1) ->
true
;
% we've been there, but were we there as a father or as a kid?
not_in(Evs0, V),
Visited1 = Visited0
),
!,
dgraph_neighbors(V, RG, Parents),
add_parents(Parents, G, RG, Is0, Is1, [V|Evs0], EvsI, Visited1, VisitedI),
(Is1 = Is0 ->
% ignore whatever we did with this node,
% it didn't lead anywhere (all parents have evidence).
add_kids(Vs, G, RG, Is0, IsF, [V|Evs0], EvsF, Visited1, VisitedF)
;
% insert parents
add_kids(Vs, G, RG, Is1, IsF, EvsI, EvsF, VisitedI, VisitedF)
).
add_kids([_|Vs], G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF) :-
add_kids(Vs, G, RG, Is0, IsF, Evs0, EvsF, Visited0, VisitedF).
not_in([V1|_], V) :- V1 == V, !, fail.
not_in([_|Evs0], V) :-
not_in(Evs0, V).
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