Returns a map between two Beilinson generators (i.e. the beilinson generators beilinsonBundle(a, E) of the derived category). Note:
(1) (S,E) is the result of productOfProjectiveSpaces
(2) e is a homogeneous element of E giving a map from E(-coldeg) --> E(-rowdeg).
i1 : (S,E) = productOfProjectiveSpaces {2,1}
o1 = (S, E)
o1 : Sequence
|
i2 : gens S, gens E
o2 = ({x , x , x , x , x }, {e , e , e , e , e })
0,0 0,1 0,2 1,0 1,1 0,0 0,1 0,2 1,0 1,1
o2 : Sequence
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i3 : f=e_(0,0)*e_(0,1)*e_(1,0)
o3 = e e e
0,0 0,1 1,0
o3 : E
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i4 : beilinsonContraction(f,{0,0},{2,1})
o4 = | x_(0,2)x_(1,1) |
1 1
o4 : Matrix S <--- S
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i5 : m=beilinsonContraction(e_(0,0)*e_(1,0),{0,0},{1,1})
o5 = | x_(0,1)x_(1,1) x_(0,2)x_(1,1) 0 |
1 3
o5 : Matrix S <--- S
|
E is positively graded, in contrast to the paper!