25 lines
818 B
Matlab
25 lines
818 B
Matlab
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% Implementation of a simple version of the Dijkstra shortest path algorithm
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% Returns the distances from a single vertex to all others, doesn't save the path
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%
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% INPUTS: adjacency matrix, adj (nxn), start node s (index between 1 and n)
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% OUTPUTS: shortest path length from the start node to all other nodes, 1xn
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%
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% Note: Works for a weighted/directed graph.
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% GB: last updated, September 28, 2012
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function d = simpleDijkstra(adj,s)
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n=length(adj);
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d = inf*ones(1,n); % distance s-all nodes
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d(s) = 0; % s-s distance
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T = 1:n; % node set with shortest paths not found yet
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while not(isempty(T))
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[dmin,ind] = min(d(T));
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for j=1:length(T)
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if adj(T(ind),T(j))>0 && d(T(j))>d(T(ind))+adj(T(ind),T(j))
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d(T(j))=d(T(ind))+adj(T(ind),T(j));
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end
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end
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T = setdiff(T,T(ind));
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end
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