We follow Example 15.2.1 of Fulton's book, Intersection Theory.
i1 : X = abstractVariety(1,QQ[r,s,e_1,f_1,D,K,Degrees=>{2:0,4:1}]) o1 = X o1 : an abstract variety of dimension 1 |
i2 : X.TangentBundle = abstractSheaf(X,Rank=>1,ChernClass=>1-K) o2 = a sheaf o2 : an abstract sheaf of rank 1 on X |
i3 : chi OO_X 1 o3 = integral(- -K) 2 o3 : Expression of class Adjacent |
i4 : chi OO(D) 1 o4 = integral(D - -K) 2 o4 : Expression of class Adjacent |
i5 : E = abstractSheaf(X,Rank => r, ChernClass => 1+e_1) o5 = E o5 : an abstract sheaf of rank r on X |
i6 : F = abstractSheaf(X,Rank => s, ChernClass => 1+f_1) o6 = F o6 : an abstract sheaf of rank s on X |
i7 : chi Hom(E,F) 1 o7 = integral(- -r*s*K - s*e + r*f ) 2 1 1 o7 : Expression of class Adjacent |