Given a matrix factorization (M0,M1) of a cubic f of format as indicarted in o5 below (or transposed,interchained or twisted) the ideal defined from the monad
0 ←⊕3 OX ←F ←⊕3 OX(-1) ←0
where F =coker M0(-3) is a rank 7 vectorbundle on the cubic hypersurface X=V(f) will be computed.i1 : kk=ZZ/10007;S=kk[x_0..x_4]; |
i3 : N=constructEx3(S); |
i4 : (M0,M1) = matrixFactorizationFromModule(N); |
i5 : betti M0, betti M1
0 1 0 1
o5 = (total: 18 18, total: 18 18)
0: 18 15 1: 15 .
1: . 3 2: 3 18
o5 : Sequence
|
i6 : C = curveFromMatrixFactorization(M0,M1); o6 : Ideal of S |
i7 : codim C, degree C, genus C o7 = (3, 16, 15) o7 : Sequence |