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pyramid -- computes the pyramid over a polyhedron

Synopsis

Description

pyramid takes the polyhedron P with ambient dimension n and embeds it into QQ^(n+1) on height 0 with respect to the new last variable. Then it computes the convex hull of the embedded P and the point (0,...,0,1).
i1 : P = hypercube 2

o1 = {ambient dimension => 2           }
      dimension of lineality space => 0
      dimension of polyhedron => 2
      number of facets => 4
      number of rays => 0
      number of vertices => 4

o1 : Polyhedron
i2 : Q = pyramid P

o2 = {ambient dimension => 3           }
      dimension of lineality space => 0
      dimension of polyhedron => 3
      number of facets => 5
      number of rays => 0
      number of vertices => 5

o2 : Polyhedron
i3 : vertices Q

o3 = | -1 1  -1 1 0 |
     | -1 -1 1  1 0 |
     | 0  0  0  0 1 |

              3       5
o3 : Matrix QQ  <-- QQ

Ways to use pyramid :

For the programmer

The object pyramid is a method function.