|
|
D.5.17.13 ChernClass
Procedure from library schubert.lib (see schubert_lib).
- Usage:
- ChernClass(S,i); S sheaf, i int
- Input:
- S is a sheaf, i is a nonnegative integer
- Return:
- poly
- Theory:
- This is the i-th Chern class of a sheaf
Example:
| | LIB "schubert.lib";
variety X;
X.dimension = 4;
ring r = 0,(c(1..2),d(1..3)),wp(1..2,1..3);
setring r;
X.baseRing = r;
poly c = 1 + c(1) + c(2);
poly ch = 2 + logg(c,4);
sheaf E = makeSheaf(X,ch);
sheaf S = E^3;
ChernClass(S,1);
==> 6*c(1)
ChernClass(S,2);
==> 11*c(1)^2+10*c(2)
ChernClass(S,3);
==> 6*c(1)^3+30*c(1)*c(2)
ChernClass(S,4);
==> 18*c(1)^2*c(2)+9*c(2)^2
|
See also:
topChernClass;
totalChernClass.
|
