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function engine = enter_evidence(engine, evidence)
doms = engine.fg.doms;
ndoms = length(doms);
ns = engine.fg.node_sizes;
obs = find(~isemptycell(evidence));
cobs = myintersect(obs, engine.fg.cnodes);
dobs = myintersect(obs, engine.fg.dnodes);
ns(cobs) = 0;
ns(dobs) = 1;
% prime each local kernel with evidence (if any)
local_kernel = cell(1, ndoms);
for i=1:length(engine.fg.kernels_of_type)
u = engine.fg.kernels_of_type{i};
local_kernel(u) = kernel_to_dpots(engine.fg.kernels{i}, evidence, engine.fg.domains_of_type{i});
end
% initialise all msgs to 1s
nedges = engine.fg.nedges;
msg = cell(1, nedges);
for i=1:nedges
msg{i} = dpot(engine.fg.sepset{i}, ns(engine.fg.sepset{i}));
end
prod_of_msg = cell(1, ndoms);
bel = cell(1, ndoms);
old_bel = cell(1, ndoms);
converged = 0;
iter = 1;
while ~converged & (iter <= engine.max_iter)
% each node multiplies all its incoming msgs
for i=1:ndoms
prod_of_msg{i} = dpot(doms{i}, ns(doms{i}));
nbrs = engine.fg.nbrs{i};
for j=1:length(nbrs)
ndx = engine.fg.edge_ndx(j,i);
prod_of_msg{i} = multiply_by_pot(prod_of_msg{i}, msg{ndx});
end
end
old_msg = msg;
% each node computes its local belief
for i=1:ndoms
bel{i} = normalize_pot(multiply_pots(prod_of_msg{i}, local_kernel{i}));
end
% converged?
converged = 1;
for i=1:ndoms
if ~approxeq(bel{i}, old_bel{i}, engine.tol)
converged = 0;
break;
end
end
if ~converged
% each node sends a msg to each of its neighbors
for i=1:ndoms
nbrs = engine.fg.nbrs{i};
for j=1:length(nbrs)
% multiply all incoming msgs except from j
temp = prod_of_msg{i};
ndx = engine.fg.edge_ndx(j,i);
temp = divide_by_pot(temp, old_msg{ndx});
% send msg from i to j
temp = multiply_by_pot(temp, local_kernel{i});
ndx = engine.fg.edge_ndx(i,j);
msg{ndx} = normalize_pot(marginalize_pot(temp, engine.fg.sepset{ndx}));
end
end
end
iter = iter + 1;
end
engine.marginal = bel;
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