matlab实现dijkstra算法

以下是 MATLAB 实现 Dijkstra 算法的示例代码：

function [D, P] = dijkstra(G, s)
% DIJKSTRA - Dijkstra's shortest path algorithm
%   [D, P] = DIJKSTRA(G, s) returns the shortest distance D from s to all
%   other nodes and the path P from s to each of the other nodes in the
%   directed graph G represented by an adjacency matrix.
%
% Written by W.-Y. Chen and C.-H. Shen, 2010
% Modified by X.-Y. Li, 2012

n = size(G, 1);         % number of nodes
D = Inf(1, n);          % initialize distances
D(s) = 0;

P = zeros(n, n);
for i = 1:n
    if G(s, i) ~= Inf
        P(i, :) = G(s, :);
    end
end

S = 1:n;                % set of nodes whose shortest path is not yet known
while ~isempty(S)
    [d, u] = min(D(S)); % find the node with the smallest distance
    if isinf(d)
        break;
    end
    S(u) = [];          % remove the node from S
    for v = 1:n
        if ~ismember(v, S) || G(u, v) == Inf
            continue;
        end
        if D(u) + G(u, v) < D(v)
            D(v) = D(u) + G(u, v);
            P(v, :) = P(u, :);
            P(v, v) = 1;
        end
    end
end

在这个算法中，G 是一个 n x n 的邻接矩阵，表示有向图中每个节点之间的距离。s 是源节点的索引。该算法返回的 D 是一个包含源节点到其他每个节点的最短路径的数组，P 是一个包含从源节点到其他每个节点的路径的数组。