Degree matrix
= Degree matrix
{title2=$D=\operatorname{diag}(d_1,\ldots,d_n)$}
The <degree matrix> is the <diagonal matrix> whose $i$th diagonal entry is the <degree of a vertex> $i$. For a finite <simple graph>, $d_i=\sum_jA_{ij}$, where $A$ is its <adjacency matrix>. For a <Weighted graph Laplacian>, use the sum of incident <edge> weights instead of the number of incident <edges>.