HEMDAG (version 2.6.1)

adj.upper.tri: Binary Upper Triangular Adjacency Matrix

Description

This function returns a binary square upper triangular matrix where rows and columns correspond to the nodes' name of the graph g.

Usage

adj.upper.tri(g)

Arguments

g

a graph of class graphNELL representing the hierarchy of the class.

Value

an adjacency matrix which is square, logical and upper triangular.

Details

The nodes of the matrix are topologically sorted (by using the tsort function of the RBGL package). Let's denote with adj our adjacency matrix. Then adj represents a partial order data set in which the class j dominates the class i. In other words, adj[i,j]=1 means that j dominates i; adj[i,j]=0 means that there is no edge between the class i and the class j. Moreover the nodes of adj are ordered such that adj[i,j]=1 implies \(i < j\), i.e. adj is upper triangular.

Examples

# NOT RUN {
data(graph);
adj <- adj.upper.tri(g);
# }