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D.16.2.37 vertexAdjacencyGraph

Syntax:
Polymake::vertexAdjacencyGraph( polytope p )
Type:
list
Purpose:
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 adjacency graph of the vertices of p, the intvec in position i contains all vertices j which are connected to vertex i via an edge of p.
Example:
 
  LIB"polymake.lib";
==> Welcome to polymake
==> Copyright (c) 1997-2012
==> 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);
  list L = Polymake::vertexAdjacencyGraph(p);
==> polymake: used package cddlib
==>   Implementation of the double description method of Motzkin et al.
==>   Copyright by Komei Fukuda.
==>   http://www.ifor.math.ethz.ch/~fukuda/cdd_home/cdd.html
==> 
  L;
==> [1]:
==> 1, 0, 0, 1,
==> 1, 1, 0, 0,
==> 1, 0, 1, 0,
==> 1, 0, 0,-1,
==> 1, 0,-1, 0,
==> 1,-1, 0, 0
==> [2]:
==>    [1]:
==>       1,2,4,5
==>    [2]:
==>       0,2,3,4
==>    [3]:
==>       0,1,3,5
==>    [4]:
==>       1,2,4,5
==>    [5]:
==>       0,1,3,5
==>    [6]:
==>       0,2,3,4