kenneth H rosen 7th ed. Ex- 10.3 q-28

Question

What is the sum of the entries in a row of the adjacency
matrix for an undirected graph? For a directed graph?

Answer 1

The adjacency matrix has rows and columns labelled by the vertices and A(i,j) has value 1 if there exists an edge between Ai and Aj, otherwise. So the sum of the entries in the row for vertex is the degree of v. :)

Answer 2

for undirected graph , sum of entries give degree of the vertex and for the directed graph it gives the outdegree of the graph.

go to this page       http://mathonline.wikidot.com/adjacency-matrices