calculate the euclidean distance among all the pairs of nodes and use those resulting distances as the edges weights of the graph

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Sim on 24 Jan 2023
Commented: Sim on 24 Jan 2023
Given the positions of nodes in a graph, i.e. x and y coordinates of each node, is there any compact way to
1. calculate the euclidean distance among all the pairs of nodes
2. and use those resulting distances as the edges weights of the graph ?
% input
s = [1 1 1 2 3 3 4 4 5 6 7 6 8 9 10 10 12 12 13 14 15 16 17 17 18 19 20 21 20 25];
t = [2 8 18 3 4 23 5 21 6 7 8 11 9 10 11 12 14 13 15 18 16 17 18 25 19 20 1 22 24 26];
G = graph(s,t);
x = [0.5 0 0 0 0.5 1 1.5 2 3 3 3 5.5 6 4 6 6 4 3 2 0.5 -1 -2 -1 1.5 4.5 4.5];
y = [0 0.5 1 1.5 2 2 1.5 1 1 1.5 2 1 0.5 0.5 0 -1 -1 -0.5 -1 -1 1 0.5 0.5 -0.5 -0.5 0];
plot(G,'XData',x,'YData',y,'linewidth',2,'MarkerSize',7);
>> G
G =
graph with properties:
Edges: [30×1 table]
Nodes: [26×0 table]
% Example of distance between node 1 and node 2:
d_12 = sqrt( (0.5-0)^2 + (-0.5+0)^2 )

Matt J on 24 Jan 2023
This is already done in spatialgraph2d()
which I think you are familiar with.
% input
s = [1 1 1 2 3 3 4 4 5 6 7 6 8 9 10 10 12 12 13 14 15 16 17 17 18 19 20 21 20 25];
t = [2 8 18 3 4 23 5 21 6 7 8 11 9 10 11 12 14 13 15 18 16 17 18 25 19 20 1 22 24 26];
G = graph(s,t);
x = [0.5 0 0 0 0.5 1 1.5 2 3 3 3 5.5 6 4 6 6 4 3 2 0.5 -1 -2 -1 1.5 4.5 4.5];
y = [0 0.5 1 1.5 2 2 1.5 1 1 1.5 2 1 0.5 0.5 0 -1 -1 -0.5 -1 -1 1 0.5 0.5 -0.5 -0.5 0];
obj=spatialgraph2D(G,x,y);
obj.G.Edges
ans = 30×2 table
EndNodes Weight ________ _______ 1 2 0.70711 1 8 1.8028 1 18 2.5495 1 20 1 2 3 0.5 3 4 0.5 3 23 1.118 4 5 0.70711 4 21 1.118 5 6 0.5 6 7 0.70711 6 11 2 7 8 0.70711 8 9 1 9 10 0.5 10 11 0.5
Sim on 24 Jan 2023
Thanks a lot @Matt J !! Oh Yes, a silly question, I did not think at all of using spatialgraph2d() :-) :-)