ccRefinement -- computes the coarsest common refinement of a set of rays

i1 : R = matrix {{1,1,-1,-1},{1,-1,1,-1},{1,1,1,1}}

o1 = | 1 1  -1 -1 |
     | 1 -1 1  -1 |
     | 1 1  1  1  |

              3       4
o1 : Matrix ZZ  <-- ZZ

i2 : F = ccRefinement R

o2 = {ambient dimension => 3         }
      number of generating cones => 4
      number of rays => 5
      top dimension of the cones => 3

o2 : Fan

i3 : rays F

o3 = {| -1 |, | 1  |, | -1 |, | 1 |, | 0 |}
      | -1 |  | -1 |  | 1  |  | 1 |  | 0 |
      | 1  |  | 1  |  | 1  |  | 1 |  | 1 |

o3 : List