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# DivisorClassRepresentativeM0nbar -- class implementing divisors on the moduli space of stable n-pointed genus zero curves

## Description

This class represents divisor classes in $ NS^1(\bar{M}_{0,n}) $. A divisor class is just a linear combination of the boundary divisors $ \delta_I $.

    i1 : H=new HashTable from { {{1,3},1}, {{1,4},1} };

    i2 : divisorClassRepresentativeM0nbar(6,H)

    o2 = DivisorClassRepresentativeM0nbar{"DivisorExpression" => HashTable{{1, 3} => 1}}
                                                                           {1, 4} => 1
                                          "NumberOfMarkedPoints" => 6

    o2 : DivisorClassRepresentativeM0nbar

## Functions and methods returning an object of class DivisorClassRepresentativeM0nbar:

- divisorClassRepresentativeM0nbar -- creates an object of type DivisorClassRepresentativeM0nbar
- writeDivisorInNonadjacentBasis -- write a divisor in the nonadjacent basis

## Methods that use an object of class DivisorClassRepresentativeM0nbar:

- DivisorClassRepresentativeM0nbar + DivisorClassRepresentativeM0nbar -- add two divisor class representatives on M0nbar
- DivisorClassRepresentativeM0nbar - DivisorClassRepresentativeM0nbar -- subtract two divisor class representatives on M0nbar
- `intersect(CurveClassRepresentativeM0nbar,DivisorClassRepresentativeM0nbar)` -- see intersect -- intersection number of a curve class and divisor class
- intersect(DivisorClassRepresentativeM0nbar,CurveClassRepresentativeM0nbar) -- intersection number of a divisor class and curve class
- isEffectiveExpression(DivisorClassRepresentativeM0nbar) -- determines whether a divisor class expression is effective
- isEquivalent(DivisorClassRepresentativeM0nbar,DivisorClassRepresentativeM0nbar) -- check whether two divisor class representatives are numerically equivalent
- Number * DivisorClassRepresentativeM0nbar -- multiply a divisor class representatives on M0nbar by a scalar
- permute(List,DivisorClassRepresentativeM0nbar) -- compute the image of a divisor class representative under a permutation of the marked points
- tex(DivisorClassRepresentativeM0nbar) -- convert to TeX format
- `writeDivisorInNonadjacentBasis(DivisorClassRepresentativeM0nbar)` -- see writeDivisorInNonadjacentBasis -- write a divisor in the nonadjacent basis

## For the programmer

The object DivisorClassRepresentativeM0nbar is a type, with ancestor classes HashTable < Thing.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/M0nbar.m2:1310:0.