Shortest path constrained to use specific nodes

Let's say I have a simple graph:
G = graph([1,2,3,4,5],[2,3,4,5,1]);
I want to find the shortest path from 1 to 3. The shortestpath function would give me 1-2-3. But in my case, I have a list of nodes that I can travel on:
nodes = [1,3,4,5];
How can I find the shortest path between any two nodes in the graph that only takes the nodes in that list (which will be 1-5-4-3 in this case)?

Réponses (3)

Matt J
Matt J le 3 Avr 2021
Modifié(e) : Matt J le 3 Avr 2021
Why not just analyze a subgraph with the inadmissible nodes removed:
cut=setdiff(1:numnodes(G),nodes);
Gsub=rmnodes(G,cut);
Here is an easy solution:
shortestpath(G, 1,3) % Shortest path between 1 and 3
Good luck.

1 commentaire

Tejas
Tejas le 3 Avr 2021
That does not answer my question, since it'll give 1-2-3, and I cannot use 2.

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Tejas
Tejas le 3 Avr 2021
Okay, I realised if I assign weights like:
G = graph([1,2,3,4,5],[2,3,4,5,1],[Inf,1,1,1,1]);
Then I do get
shortestpath(G,1,3)
ans =
1 5 4 3
I don't have any other purpose for weights so I can use them in this way.

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R2020b

Question posée :

le 3 Avr 2021

Modifié(e) :

le 3 Avr 2021

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