i want to get adjacency matrix of a network

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mks
mks on 30 Jul 2023
Commented: Steven Lord on 30 Jul 2023
i have write this but is not running
clc;
clear all
n=10;
p=0.4;
adj_matrix = generate_adjacency_matrix(n, p);
function adj_matrix = generate_adjacency_matrix(n, p)
% Initialize an n x n matrix with all zeros
adj_matrix = zeros(n, n);
% Loop through all possible node pairs
for i = 1:n
for j = 1:n
% Skip diagonal elements (no self-loops)
if i == j
continue;
end
% Generate a random number between 0 and 1
random_number = rand();
% If the random number is less than p, add a link between nodes i and j
if random_number < p
adj_matrix(i, j) = 1;
adj_matrix(j, i) = 1; % Since it's an undirected network
end
end
end
end
disp(adj_matrix);

Answers (2)

Matt J
Matt J on 30 Jul 2023
Edited: Matt J on 30 Jul 2023
Easier:
function adj_matrix = generate_adjacency_matrix(n, p)
adj_matrix=triu(rand(n)<p,1);
adj_matrix=adj_matrix+adj_matrix'; % Since it's an undirected network
end

Steven Lord
Steven Lord on 30 Jul 2023
If you want to generate both the graph object and its adjacency matrix, tell MATLAB to build the graph using just the upper triangular part of the random matrix.
n = 10;
p = 0.6;
A = rand(n) < p;
G = graph(A, 'upper');
adj = full(adjacency(G))
adj = 10×10
0 0 1 0 0 1 0 1 0 0 0 1 0 1 1 1 0 1 1 1 1 0 1 1 0 1 0 1 0 1 0 1 1 1 1 1 0 1 1 1 0 1 0 1 1 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 0 0 0 0 0 0 0 1 0 1 1 1 1 1 1 0 1 1 0 0 0 1 0 1 1 1 0 0 1 1 0 1 1 1 1 0 1 0 1 1
check = triu(A)+triu(A, 1).'
check = 10×10
0 0 1 0 0 1 0 1 0 0 0 1 0 1 1 1 0 1 1 1 1 0 1 1 0 1 0 1 0 1 0 1 1 1 1 1 0 1 1 1 0 1 0 1 1 1 0 1 1 1 1 1 1 1 1 1 0 0 1 0 0 0 0 0 0 0 0 1 0 1 1 1 1 1 1 0 1 1 0 0 0 1 0 1 1 1 0 0 1 1 0 1 1 1 1 0 1 0 1 1
isequal(adj, check)
ans = logical
1
  2 Comments
mks
mks on 30 Jul 2023
Moved: Bruno Luong on 30 Jul 2023
how can draw it ?
Steven Lord
Steven Lord on 30 Jul 2023
Since I created the graph object before creating the adjacency matrix, just plot it.
plot(G)

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