i1 : base(3, Bundle => (A,2,a), Bundle => (B,3,b)) o1 = a variety o1 : an abstract variety of dimension 3 |
i2 : chern B o2 = 1 + b + b + b 1 2 3 o2 : QQ[a , a , b , b , b ] 1 2 1 2 3 |
i3 : chern(-A) 2 3 o3 = 1 - a + (a - a ) + (- a + 2a a ) 1 1 2 1 1 2 o3 : QQ[a , a , b , b , b ] 1 2 1 2 3 |
i4 : pt = base(n,p,q) o4 = pt o4 : an abstract variety of dimension 0 |
i5 : P2 = projectiveSpace'_2 pt o5 = P2 o5 : a flag bundle with ranks {2, 1} |
i6 : E = abstractSheaf(P2, Rank=>2, ChernClass=>1+p*h+q*h^2) o6 = E o6 : an abstract sheaf of rank 2 on P2 |
i7 : chern E(n*h) 2 2 o7 = 1 + (2n + p)h + (n + n*p + q)h QQ[n, p, q][H , H , h] 1,1 1,2 o7 : ------------------------------- (H + h, H + H h, H h) 1,1 1,2 1,1 1,2 |