Mauch MIREX 2010

function y = sample_node(CPD, pev)

% SAMPLE_NODE Draw a random sample from P(Xi | x(pi_i), theta_i)  (gaussian)

% y = sample_node(CPD, parent_evidence)

%

% pev{i} is the value of the i'th parent (if there are any parents)

% y is the sampled value (a scalar or vector)

if length(CPD.dps)==0

  i = 1;

else

  dpvals = cat(1, pev{CPD.dps});

  i = subv2ind(CPD.sizes(CPD.dps), dpvals(:)');

end

if length(CPD.cps) == 0 

  y = gsamp(CPD.mean(:,i), CPD.cov(:,:,i), 1);

else

  pev = pev(:);

  x = cat(1, pev{CPD.cps});

  y = gsamp(CPD.mean(:,i) + CPD.weights(:,:,i)*x(:), CPD.cov(:,:,i), 1);

end

y = y(:);