Number of k-stars in an adjacency matrix

Hi all,

I have an nxn adjacency matrix of a graph and want to know the number of unique 2-stars, 3-stars and triangles in the graph, is there a function I can use to do this or do code my own method?

I have to code my own method any advise on how to proceed would be appreciated.

Thank you

Answer 1

[Gaurav Garg]

Hi Daniel,

Even though you can find such patterns easily in 1-D arrays by converting them to strings (link1 and link2), it would be better if you can write such pattern funcitons for 2-D arrays.

for i=1:r
    for j=1:c
        answer = check_for_triangle(i,j);
    end
end
function check_for_triangle(r, c)
    is_present = false;
    if A(r,c) == 1
        if A(r+1,c) == 1 & A(r+1,c+1) == 1
            if A(r+2,c) == 1 & A(r+2,c+1) == 1 & A(r+2,c+2) == 1
                    is_present = true;
            end
        end
    end
end

The above given pseudo-code is an example of how you can write code pattern to check for a triangle in a binary adjacency matrix.

[Daniel Stocks]

Thank you Gaurav I will look into this