I removed

The modified adjacency matrix is generated by replacing all entries greater than 1 in the adjacency matrix by 1.

from the article. The edges in graphs are defined as a set, so it is not possible that an edge (v_i,v_j) is contained more than once. I think the adjacency matrix should be a (0,1)-matrix and perhaps in a subsection someone could extend this definition to count the number of edges two vertices share.MathMartin 18:56, 25 Sep 2004 (UTC)

This is correct, although multigraphs have a multiset of edges. Derrick Coetzee 00:25, 2 Oct 2004 (UTC)

Maybe the example graph can contain a self loop, to show how it can be represented into the adjacency matrix.

That's a great idea. Deco 01:39, 21 Mar 2005 (UTC)

Most software packages show a binary adjacency matrix, even on the diagonal. But loops are always counted twice, and some books show an adjacency matrix like this one, with 2 on the diagonal...