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function y = sample_node(CPD, pvals)
% SAMPLE_NODE Draw a random sample from P(Xi | x(pi_i), theta_i) (discrete)
% y = sample_node(CPD, parent_evidence)
%
% parent_evidence{i} is the value of the i'th parent
if 0
n = length(pvals)+1;
dom = 1:n;
evidence = cell(1,n);
evidence(1:n-1) = pvals;
T = convert_to_table(CPD, dom, evidence);
y = sample_discrete(T);
end
CPT = CPD_to_CPT(CPD);
sz = mysize(CPT);
nparents = length(sz)-1;
switch nparents
case 0, T = CPT;
case 1, T = CPT(pvals{1}, :);
case 2, T = CPT(pvals{1}, pvals{2}, :);
case 3, T = CPT(pvals{1}, pvals{2}, pvals{3}, :);
case 4, T = CPT(pvals{1}, pvals{2}, pvals{3}, pvals{4}, :);
otherwise,
pvals = cat(1, pvals{:});
psz = sz(1:end-1);
ssz = sz(end);
i = subv2ind(psz, pvals(:)');
T = reshape(CPT, [prod(psz) ssz]);
T = T(i,:);
end
y = sample_discrete(T);
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