Get shortest paths and distances among nodes without loop for (and possibly in a faster way)

Question

Sim 2022-12-16

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1879642-get-shortest-paths-and-distances-among-nodes-without-loop-for-and-possibly-in-a-faster-way

评论： Jon 2022-12-16

How to get shortest paths and distances among nodes (selected from a list) without a loop for, and possibly in a faster way than what shown in the following example ?

% Input 1 (the graph)

s = [1 1 1 1 2 2 2 2 2 8 8 12 14 14 1 14];

t = [3 5 4 2 6 10 7 9 8 11 12 13 7 6 8 15];

G = graph(s,t);

plot(G)

% Input 2 (list of nodes, among which, both shortest paths and distances will be

% calculated)

list = [3 7 8 9 10 14];

% Calculation

tic

for i = 1 :length(list)

for j = 1 : length(list)

[p,d] = shortestpath(G,list(i),list(j));

nodes_path{i,j} = p;

nodes_distances{i,j} = d;

end

toc

Elapsed time is 0.016856 seconds.

% Outputs

nodes_path,

nodes_path = 6×6 cell array

{[ 3]} {[3 1 2 7]} {[ 3 1 8]} {[ 3 1 2 9]} {[ 3 1 2 10]} {[3 1 2 6 14]} {[ 7 2 1 3]} {[ 7]} {[ 7 2 8]} {[ 7 2 9]} {[ 7 2 10]} {[ 7 14]} {[ 8 1 3]} {[ 8 2 7]} {[ 8]} {[ 8 2 9]} {[ 8 2 10]} {[ 8 2 6 14]} {[ 9 2 1 3]} {[ 9 2 7]} {[ 9 2 8]} {[ 9]} {[ 9 2 10]} {[ 9 2 6 14]} {[ 10 2 1 3]} {[ 10 2 7]} {[ 10 2 8]} {[ 10 2 9]} {[ 10]} {[ 10 2 6 14]} {[14 6 2 1 3]} {[ 14 7]} {[14 6 2 8]} {[14 6 2 9]} {[14 6 2 10]} {[ 14]}

nodes_distances,

nodes_distances = 6×6 cell array

{[0]} {[3]} {[2]} {[3]} {[3]} {[4]} {[3]} {[0]} {[2]} {[2]} {[2]} {[1]} {[2]} {[2]} {[0]} {[2]} {[2]} {[3]} {[3]} {[2]} {[2]} {[0]} {[2]} {[3]} {[3]} {[2]} {[2]} {[2]} {[0]} {[3]} {[4]} {[1]} {[3]} {[3]} {[3]} {[0]}