If you carefully look at the plot, all 21 nodes are being displayed, but only 10 have been labelled.
Also, “segments” could be more clearly defined to prevent any confusion. Additionally, edges only exist between the first 10 nodes. You might want to add edges among the remaining nodes as well.
Here is a simple code snippet that defines an adjacency matrix for a basic graph. It uses the Dijkstra function (https://www.mathworks.com/matlabcentral/fileexchange/36140-dijkstra-algorithm) to find the shortest path between nodes 1 and 4, highlighting them in red.
% You might consider converting your graph into an adjacency matrix format and
% then using it with the function.
A = [0 1 1 1 1;
1 0 1 1 0;
1 1 0 1 1;
1 1 1 0 1;
1 0 1 1 0];
G = graph(A);
source = 1;
destination = 4;
[cost, route] = dijkstra(A, source, destination);
figure;
h = plot(G);
highlight(h, route, 'EdgeColor', 'r', 'LineWidth', 2);
highlight(h, route, 'NodeColor', 'r');
Hope this helps!
