gtsam/matlab/bottom_up_ordering.m

22 lines
621 B
Matlab

% find a bottom to up ordering given the tree structure {pred} returned by matlab's graphminspantree
function [ordering] = bottom_up_ordering(pred)
%% compute the levels of the nodes
parents = [0];
node_levels = zeros(length(pred), 1);
current_level = 1;
while ~isempty(parents)
parents = find(ismember(pred, parents));
node_levels(parents) = current_level;
current_level = current_level + 1;
end
max_level = current_level - 1;
ordering = Ordering();
for level = max_level:-1:1
ids = find(node_levels==level);
for i = 1:length(ids)
ordering.push_back(sprintf('x%d', ids(i)));
end
end
end