Daniel@0: function [err, time, engine] = cmp_inference(bnet, engine, exact, T, filter, singletons, maximize)
Daniel@0: % CMP_INFERENCE Compare several inference engines on a DBN
Daniel@0: % [err, time, engine] = cmp_inference(bnet, engine, exact, T, filter, singletons, maximize)
Daniel@0: %
Daniel@0: % engine{i} is the i'th inference engine.
Daniel@0: % 'exact' specifies which engines do exact inference - 
Daniel@0: %   we check that these all give the same results.
Daniel@0: % 'T' is the length of the random sequence we generate.
Daniel@0: % If filter=1, we do filtering, else smoothing (default: smoothing)
Daniel@0: % If singletons=1, we compare marginal_nodes, else marginal_family (default: family)
Daniel@0: %
Daniel@0: % err(e,n,t) = sum_i | Pr_exact(X(n,t)=i) - Pr_e(X(n,t)=i) |
Daniel@0: %   where Pr_e = prob. according to engine e
Daniel@0: % time(e) = elapsed time for doing inference with engine e
Daniel@0: 
Daniel@0: err = [];
Daniel@0: 
Daniel@0: if nargin < 5, filter = 0; end
Daniel@0: if nargin < 6, singletons = 0; end
Daniel@0: if nargin < 7, maximize = 0; end
Daniel@0: 
Daniel@0: check_ll = 1;
Daniel@0: 
Daniel@0: assert(~maximize);
Daniel@0: 
Daniel@0: E = length(engine);
Daniel@0: ref = exact(1); % reference
Daniel@0: 
Daniel@0: ss = length(bnet.intra);
Daniel@0: ev = sample_dbn(bnet, 'length', T);
Daniel@0: evidence = cell(ss,T);
Daniel@0: onodes = bnet.observed;
Daniel@0: evidence(onodes,:) = ev(onodes, :);
Daniel@0: 
Daniel@0: assert(~filter);
Daniel@0: for i=1:E
Daniel@0:   tic;
Daniel@0:   %[engine{i}, ll(i)] = enter_evidence(engine{i}, evidence, 'maximize', maximize);
Daniel@0:   [engine{i}, ll(i)] = enter_evidence(engine{i}, evidence);
Daniel@0:   time(i)=toc;
Daniel@0:   fprintf('engine %d took %6.4f seconds\n', i, time(i));
Daniel@0: end
Daniel@0: 
Daniel@0: cmp = mysetdiff(exact, ref);
Daniel@0: if check_ll
Daniel@0: for i=cmp(:)'
Daniel@0:   if ~approxeq(ll(ref), ll(i))
Daniel@0:     error(['engine ' num2str(i) ' has wrong ll'])
Daniel@0:   end
Daniel@0: end
Daniel@0: end
Daniel@0: ll
Daniel@0: 
Daniel@0: hnodes = mysetdiff(1:ss, onodes);
Daniel@0: m = cell(1,E);
Daniel@0: for t=1:T
Daniel@0:   for n=hnodes(:)'
Daniel@0:     for e=1:E
Daniel@0:       if singletons
Daniel@0: 	m{e} = marginal_nodes(engine{e}, n, t);
Daniel@0:       else
Daniel@0: 	m{e} = marginal_family(engine{e}, n, t);
Daniel@0:       end
Daniel@0:     end
Daniel@0:     for e=1:E
Daniel@0:       assert(isequal(m{e}.domain, m{ref}.domain));
Daniel@0:     end
Daniel@0:     for e=cmp(:)'
Daniel@0:       if ~approxeq(m{ref}.T(:), m{e}.T(:))
Daniel@0: 	str= sprintf('engine %d is wrong; n=%d, t=%d', e, n, t);
Daniel@0: 	error(str)
Daniel@0:       end
Daniel@0:     end
Daniel@0:   end
Daniel@0: end