matroid arr
This computes the a matroid of the given arrangement, which by definition is the matroid defined by the coefficient matrix of the arrangement.
i1 : A = matrix{{1,1,0},{-1,0,1},{0,-1,-1}} o1 = | 1 1 0 | | -1 0 1 | | 0 -1 -1 | 3 3 o1 : Matrix ZZ <-- ZZ
i2 : arr = arrangement A o2 = {x - x , x - x , x - x } 1 2 1 3 2 3 o2 : Hyperplane Arrangement
i3 : matroid arr o3 = a "matroid" of rank 2 on 3 elements o3 : Matroid