-- -*- M2-comint -*- {* hash: -1300284785 *} i1 : C1 = posHull matrix {{1,0},{0,1}}; i2 : C2 = posHull matrix {{1,-1},{0,-1}}; i3 : C3 = posHull matrix {{1,-1},{2,-1}}; i4 : commonFace(C1,C2) o4 = true i5 : commonFace(C2,C3) o5 = true i6 : commonFace(C3,C1) o6 = false i7 :