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# KClass + KClass -- computes the sum of two equivariant K-classes

- Operator: +
- Usage:
    `C1 + C2`
- Inputs:
  - C1, an equivariant K-class,
  - C2, an equivariant K-class,
- Outputs:
  - an equivariant K-class, the sum of C1 and C2

## Description

This method computes the sum of two equivariant $K$-classes.

    i1 : Gr24 = generalizedFlagVariety("A",3,{2}); --the Grassmannian of projective lines in projective 3-space

    i2 : O1 = ampleKClass Gr24 -- the O(1) bundle on Gr24 as an equivariant K-class

    o2 = an "equivariant K-class" on a GKM variety

    o2 : KClass

    i3 : E = O1 + (O1*O1)

    o3 = an "equivariant K-class" on a GKM variety

    o3 : KClass

    i4 : peek E

    o4 = KClass{variety => a "GKM variety" with an action of a 4-dimensional torus}
                                                           2 2
                KPolynomials => HashTable{{set {0, 1}} => T T  + T T }
                                                           0 1    0 1
                                                           2 2
                                          {set {0, 2}} => T T  + T T
                                                           0 2    0 2
                                                           2 2
                                          {set {0, 3}} => T T  + T T
                                                           0 3    0 3
                                                           2 2
                                          {set {1, 2}} => T T  + T T
                                                           1 2    1 2
                                                           2 2
                                          {set {1, 3}} => T T  + T T
                                                           1 3    1 3
                                                           2 2
                                          {set {2, 3}} => T T  + T T
                                                           2 3    2 3

## See also

- makeKClass -- constructs an equivariant K-class
- KClass * KClass -- computes the product of two equivariant K-classes

## Ways to use this method:

- KClass + KClass -- computes the sum of two equivariant K-classes

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/GKMVarieties/Documentation_GKMVarieties.m2:769:0.