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1 function pot = convert_to_pot(CPD, pot_type, domain, evidence)
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2 % CONVERT_TO_POT Convert a tabular CPD to one or more potentials
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3 % pots = convert_to_pot(CPD, pot_type, domain, evidence)
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4 %
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5 % pots{i} = CPD evaluated using evidence(domain(:,i))
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6 % If 'domains' is a single row vector, pots will be an object, not a cell array.
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7
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8 ncases = size(domain,2);
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9 assert(ncases==1); % not yet vectorized
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10
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11 sz = dom_sizes(CPD);
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12 ns = zeros(1, max(domain));
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13 ns(domain) = sz;
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14
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15 local_ev = evidence(domain);
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16 obs_bitv = ~isemptycell(local_ev);
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17 odom = domain(obs_bitv);
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18 T = convert_to_table(CPD, domain, local_ev, obs_bitv);
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19
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20 switch pot_type
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21 case 'u',
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22 pot = upot(domain, sz, T, 0*myones(sz));
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23 case 'd',
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24 ns(odom) = 1;
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25 pot = dpot(domain, ns(domain), T);
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26 case {'c','g'},
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27 % Since we want the output to be a Gaussian, the whole family must be observed.
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28 % In other words, the potential is really just a constant.
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29 p = T;
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30 %p = prob_node(CPD, evidence(domain(end)), evidence(domain(1:end-1)));
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31 ns(domain) = 0;
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32 pot = cpot(domain, ns(domain), log(p));
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33 case 'cg',
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34 T = T(:);
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35 ns(odom) = 1;
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36 can = cell(1, length(T));
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37 for i=1:length(T)
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38 can{i} = cpot([], [], log(T(i)));
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39 end
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40 pot = cgpot(domain, [], ns, can);
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41 otherwise,
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42 error(['unrecognized pot type ' pot_type])
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43 end
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44
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