-- -*- M2-comint -*- hash: 17384060046450518319

i1 : P = convexHull(matrix {{1,-1,2,-2},{1,1,2,2}}, matrix {{0},{1}})

o1 = {ambient dimension => 2           }
      dimension of lineality space => 0
      dimension of polyhedron => 2
      number of facets => 5
      number of rays => 1
      number of vertices => 4

o1 : Polyhedron

i2 : rays P

o2 = | 0 |
     | 1 |

              2       1
o2 : Matrix ZZ  <-- ZZ

i3 : C = posHull P

o3 = {ambient dimension => 2           }
      dimension of lineality space => 0
      dimension of the cone => 2
      number of facets => 2
      number of rays => 2

o3 : Cone

i4 : rays C

o4 = | -1 1 |
     | 1  1 |

              2       2
o4 : Matrix ZZ  <-- ZZ

i5 : F = normalFan P

o5 = {ambient dimension => 2         }
      number of generating cones => 4
      number of rays => 5
      top dimension of the cones => 2

o5 : Fan

i6 : rays F

o6 = {| -1 |, | 1 |, | 0 |, | -1 |, | 1 |}
      | 1  |  | 1 |  | 1 |  | 0  |  | 0 |

o6 : List

i7 : 
