Chooses a random extension of V2 by V1, where V1, V2 are vector bundles on E represented by the type VectorBundleOnE.
i1 : kk=ZZ/101;
|
i2 : g=1;
|
i3 : rNP=randNicePencil(kk,g);
|
i4 : cM=cliffordModule(rNP.matFact1,rNP.matFact2,rNP.baseRing);
|
i5 : f=cM.hyperellipticBranchEquation
3 2 2 3 4
o5 = - 12s t - 50s t - 16s*t + 47t
o5 : kk[s, t]
|
i6 : L1=randomLineBundle(0,f)
o6 = VectorBundleOnE{...1...}
o6 : VectorBundleOnE
|
i7 : L2=randomLineBundle(2,f)
o7 = VectorBundleOnE{...1...}
o7 : VectorBundleOnE
|
i8 : V=randomExtension(L1,L2)
o8 = VectorBundleOnE{...1...}
o8 : VectorBundleOnE
|
i9 : V.yAction
o9 = {-1} | -18s2-13st-43t2 13s2+45st-16t2 40s4+37s3t+16s2t2+35st3
{-1} | 45s2-14st-t2 18s2+13st+43t2 11s4+45s3t+6s2t2-5st3+3t4
{1} | 0 0 48s2+36st+35t2
{-1} | 0 0 44s4+s3t-22s2t2+33st3-t4
------------------------------------------------------------------------
-42s2-33st-48t2 |
39s2-30st+32t2 |
-34 |
-48s2-36st-35t2 |
4 4
o9 : Matrix (kk[s, t]) <-- (kk[s, t])
|
i10 : degOnE V
o10 = 2
|
i11 : V1=randomExtension(L2,V)
o11 = VectorBundleOnE{...1...}
o11 : VectorBundleOnE
|
i12 : V1.yAction
o12 = {1} | 48s2+36st+35t2 -34 36
{-1} | 44s4+s3t-22s2t2+33st3-t4 -48s2-36st-35t2 29s2+40st-43t2
{-1} | 0 0 -18s2-13st-43t2
{-1} | 0 0 45s2-14st-t2
{1} | 0 0 0
{-1} | 0 0 0
-----------------------------------------------------------------------
-38 -22s2-40st+6t2 -29 |
41s2-19st-15t2 -28s4-20s3t+11s2t2+31st3-5t4 29s2-3st+50t2 |
13s2+45st-16t2 40s4+37s3t+16s2t2+35st3 -42s2-33st-48t2 |
18s2+13st+43t2 11s4+45s3t+6s2t2-5st3+3t4 39s2-30st+32t2 |
0 48s2+36st+35t2 -34 |
0 44s4+s3t-22s2t2+33st3-t4 -48s2-36st-35t2 |
6 6
o12 : Matrix (kk[s, t]) <-- (kk[s, t])
|
i13 : degOnE V1
o13 = 4
|