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base -- an abstract variety, defined with some parameters and some bundles

Synopsis

Description

The symbols p,q... can be used as integer variables in Chow ring computations
i1 : X=base(1,p,q,Bundle=>(A,1,a), Bundle=>(B,1,b))

o1 = X

o1 : an abstract variety of dimension 1
i2 : Y=projectiveSpace(3,X,VariableName=>H)

o2 = Y

o2 : a flag bundle with ranks {3, 1}
i3 : f=Y.StructureMap

o3 = f

o3 : a map to X from Y
i4 : x=chern f_*((f^*(OO_X(p*a_1)))*OO_Y(q*H))

          1   3        2     11
o4 = 1 + (-p*q a  + p*q a  + --p*q*a  + p*a )
          6     1        1    6     1      1

o4 : QQ[p, q, a , b ]
               1   1
i5 : y=chern f_*OO_Y((f^*(p*a_1))+q*H)

          1   3        2     11
o5 = 1 + (-p*q a  + p*q a  + --p*q*a  + p*a )
          6     1        1    6     1      1

o5 : QQ[p, q, a , b ]
               1   1
i6 : x==y

o6 = true

Caveat

Be sure that A... are symbols; if they have already been defined there will be trouble.

See also

Ways to use base :