# Singular

#### D.13.2.55 vertexEdgeGraph

Procedure from library `polymake.lib` (see polymake_lib).

Usage:
vertexEdgeGraph(p); p polytope

Return:
list, the first entry is a bigintmat containing all vertices as row vectors, and therefore assigning all vertices an integer. the second entry is a list of intvecs representing the edge graph of the vertices of p, each intvec represents an edge of p connecting vertex i with vertex j.

Example:
 ```LIB "polymake.lib"; ==> Welcome to polymake version ==> Copyright (c) 1997-2015 ==> Ewgenij Gawrilow, Michael Joswig (TU Darmstadt) ==> http://www.polymake.org intmat M[6][4] = 1,1,0,0, 1,0,1,0, 1,0,-1,0, 1,0,0,1, 1,0,0,-1, 1,-1,0,0; polytope p = polytopeViaPoints(M); vertexEdgeGraph(p); ==> polymake: used package ppl ==> The Parma Polyhedra Library (PPL): A C++ library for convex polyhedra ==> and other numerical abstractions. ==> http://www.cs.unipr.it/ppl/ ==> ==> [1]: ==> 1, 0, 0,-1, ==> 1, 0,-1, 0, ==> 1,-1, 0, 0, ==> 1, 0, 0, 1, ==> 1, 0, 1, 0, ==> 1, 1, 0, 0 ==> [2]: ==> [1]: ==> 0,1 ==> [2]: ==> 0,2 ==> [3]: ==> 0,4 ==> [4]: ==> 0,5 ==> [5]: ==> 1,2 ==> [6]: ==> 1,3 ==> [7]: ==> 1,5 ==> [8]: ==> 2,3 ==> [9]: ==> 2,4 ==> [10]: ==> 3,4 ==> [11]: ==> 3,5 ==> [12]: ==> 4,5 ```