Using Dijkstra algorithm.

I found this function

function [dist,path] = CSDG_Dijkstra_SP(nodes,segments,start_id,finish_id,L,PlotFlags);

which allows me to calculate the the shortest distance and path between points on a map. The inputs I need are "nodes", "segments", "start_id", and "finish_id". I already have the following:

    xyNode=randi([1,100],N,2);
    ID=[1:N]'
    nodes=[ID,xyNode(:,1),xyNode(:,2)];

and start_id is the number of the node among N nodes that I have in my map. finish_id is for another node(different from this N nodes. It is the sink node) which is placed in certain position (center of the map). For this I wrote:

for n=1:N
    start_id=n;
    finish_id=(100*sqrt(N)/2),(100*sqrt(N)/2);
    [dist,path]=CSDG_Dijkstra_SPT(nodes,segments,start_id,finish_id)
    output(:,:,n)=[dist,path];
end

As it is defined in this function, the input "segments" should be an Mx3 matrix with the format [ID N1 N2] where ID is an integer, and N1, N2 correspond to node IDs from NODES list such that there is an [undirected] edge/segment between node N1 and node N2.

I've been told that two nodes are able to communicate if the distance between them is less than 100*sqrt(5).

How can I get the segments input with this information?

I'll be very grateful for any help.