2.1 Cyberspace representation
The information in the graph may also be expressed in a variety of ways in matrix form. There is one such matrix, the adjacency matrix, that is especially useful. An adjacency matrix of the graph is of size . The entries in the adjacency matrix, , records which pairs of nodes are adjacent. If nodes and are adjacent, then , and if nodes and are not adjacent, then . The entries on the diagonal, values of , are undefined, because we do not allow loops in the graph.
The following elements are introduced to extract features and components of the graph :