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root / _FullBNT / BNT / CPDs / @discrete_CPD / Old / convert_to_pot.m @ 8:b5b38998ef3b
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function pot = convert_to_pot(CPD, pot_type, domain, evidence) |
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% CONVERT_TO_POT Convert a tabular CPD to one or more potentials |
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% pots = convert_to_pot(CPD, pot_type, domain, evidence) |
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% |
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% pots{i} = CPD evaluated using evidence(domain(:,i))
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% If 'domains' is a single row vector, pots will be an object, not a cell array. |
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ncases = size(domain,2); |
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assert(ncases==1); % not yet vectorized |
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sz = dom_sizes(CPD); |
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ns = zeros(1, max(domain)); |
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ns(domain) = sz; |
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local_ev = evidence(domain); |
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obs_bitv = ~isemptycell(local_ev); |
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odom = domain(obs_bitv); |
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T = convert_to_table(CPD, domain, local_ev, obs_bitv); |
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switch pot_type |
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case 'u', |
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pot = upot(domain, sz, T, 0*myones(sz)); |
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case 'd', |
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ns(odom) = 1; |
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pot = dpot(domain, ns(domain), T); |
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case {'c','g'},
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% Since we want the output to be a Gaussian, the whole family must be observed. |
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% In other words, the potential is really just a constant. |
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p = T; |
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%p = prob_node(CPD, evidence(domain(end)), evidence(domain(1:end-1))); |
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ns(domain) = 0; |
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pot = cpot(domain, ns(domain), log(p)); |
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case 'cg', |
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T = T(:); |
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ns(odom) = 1; |
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can = cell(1, length(T)); |
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for i=1:length(T) |
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can{i} = cpot([], [], log(T(i)));
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end |
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pot = cgpot(domain, [], ns, can); |
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otherwise, |
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error(['unrecognized pot type ' pot_type]) |
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end |
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