IncidenceMatrix

The vertex-by-edge incidence matrix of a Graph.

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IncidenceMatrix(g)row = vertex (in VertexList order), column = edge (in EdgeList order). An undirected edge puts 1 in both its endpoints' rows; a directed edge puts -1 at its source and 1 at its target.

Typed signatures

Type	Package	Applies
(value) -> list<list<integer>>	combinatorics	always

Domain: Collections

Details

• Returned as a plain matrix (a list of lists), same convention as AdjacencyMatrix.

Examples

Basic #

One undirected edge, one directed edge

live ↗

In$\mathrm{IncidenceMatrix}(\mathrm{Graph}(\bigl\lbrack1, 2, 3\bigr\rbrack, \bigl\lbrack\mathrm{UndirectedEdge}(1, 2), \mathrm{DirectedEdge}(2, 3)\bigr\rbrack))$Out$\bigl\lbrack\bigl\lbrack1, 0\bigr\rbrack, \bigl\lbrack1, -1\bigr\rbrack, \bigl\lbrack0, 1\bigr\rbrack\bigr\rbrack$

About

Examples	1
Checked against	Wolfram Language 1 differ
Crosswalk	Wolfram Language

See also: AdjacencyMatrix, EdgeList