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1 function CPT2 = mk_named_CPT(family_names, names, dag, CPT1)
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2 % MK_NAMED_CPT Permute the dimensions of a CPT so they agree with the internal numbering convention
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3 % CPT2 = mk_named_CPT(family_names, names, dag, CPT1)
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4 %
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5 % This is best explained by example.
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6 % Consider the following directed acyclic graph
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7 %
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8 % C
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9 % / \
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10 % R S
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11 % \ /
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12 % W
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13 %
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14 % where all arcs point down.
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15 % When we create the CPT for node W, we consider S as its first parent, and R as its
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16 % second, and hence write
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17 %
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18 % S R W
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19 % CPT1(1,1,:) = [1.0 0.0];
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20 % CPT1(2,1,:) = [0.2 0.8]; % P(W=1 | R=1, S=2) = 0.2
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21 % CPT1(1,2,:) = [0.1 0.9];
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22 % CPT1(2,2,:) = [0.01 0.99];
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23 %
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24 % However, when we create the dag using mk_adj_mat, the nodes get topologically sorted,
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25 % and by chance, node R preceeds node S in this ordering.
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26 % Hence we should have written
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27 %
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28 % R S W
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29 % CPT2(1,1,:) = [1.0 0.0];
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30 % CPT2(2,1,:) = [0.1 0.9];
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31 % CPT2(1,2,:) = [0.2 0.8]; % P(W=1 | R=1, S=2) = 0.2
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32 % CPT2(2,2,:) = [0.01 0.99];
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33 %
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34 % Since we do not know the order of the nodes in advance, we can write
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35 % CPT2 = mk_named_CPT({'S', 'R', 'W'}, names, dag, CPT1)
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36 % where 'S', 'R', 'W' are the order of the dimensions we assumed (the child node must be last in this list),
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37 % and names{i} is the name of the i'th node.
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38
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39 n = length(family_names);
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40 family_nums = zeros(1,n);
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41 for i=1:n
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42 family_nums(i) = stringmatch(family_names{i}, names); % was strmatch
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43 end
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44
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45 fam = family(dag, family_nums(end));
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46 perm = zeros(1,n);
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47 for i=1:n
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48 % perm(i) = find(family_nums(i) == fam);
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49 perm(i) = find(fam(i) == family_nums);
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50 end
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51
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52 CPT2 = permute(CPT1, perm);
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