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GKMVarieties :: euler(KClass)

euler(KClass) -- computes the equivariant Euler characteristic of an equivariant K-class

Synopsis

Description

This method computes the pushforward of a KClass on a GKMVariety $X$ along the structure map $X \to pt$, where $pt$ is a point with trivial torus-action.

i1 : PP3 = projectiveSpace 3

o1 = a GKM variety with an action of a 4-dimensional torus

o1 : GKMVariety
i2 : O1 = ampleKClass PP3

o2 = an equivariant K-class on a GKM variety 

o2 : KClass
i3 : euler O1

o3 = T  + T  + T  + T
      0    1    2    3

o3 : ZZ[T ..T ]
         0   3

See also