wolffd@0: function [dag, order] = mk_rnd_dag(N, max_fan_in)
wolffd@0: % MY_MK_RND_DAG  Create a random directed acyclic graph
wolffd@0: %
wolffd@0: % [dag, order] = my_mk_rnd_dag(N, max_fan_in)
wolffd@0: %  max_fan_in defaults to N.
wolffd@0: %  order is the random topological order that was chosen
wolffd@0: 
wolffd@0: % Modified by Sonia Leach 2/25/02
wolffd@0: 
wolffd@0: if nargin < 2, max_fan_in = N; end
wolffd@0: 
wolffd@0: order = randperm(N);
wolffd@0: dag = zeros(N,N);
wolffd@0: for i=2:N
wolffd@0:   j = order(i);
wolffd@0:   %k = sample_discrete(normalise(ones(1, min(i-1, max_fan_in))));
wolffd@0:   k = sample_discrete(normalise(ones(1, min(i-1, max_fan_in)+1))) - 1; % min = 0 (bug fix due to
wolffd@0:                                                                        % Pedrito, 7/28/04)
wolffd@0:   SS = order(1:i-1);          % get Set of possible parentS
wolffd@0:   p  = randperm(length(SS));  % permute order of set
wolffd@0:   dag(SS(p(1:k)),j) = 1;      % take first k in permuted order
wolffd@0: 
wolffd@0:   % Kevin had:
wolffd@0:   %SS = subsets(order(1:i-1), k, k);
wolffd@0:   %p = sample_discrete(normalise(ones(1, length(SS))));
wolffd@0:   %dag(SS{p}, j) = 1;
wolffd@0: end