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# isEquivalent -- check whether two curve class representatives are numerically equivalent

- Usage:
    `isEquivalent(C1,C2)`
- Inputs:
  - C1, an instance of the type CurveClassRepresentativeM0nbar,
  - C2, an instance of the type CurveClassRepresentativeM0nbar,
- Outputs:
  - b, a Boolean value,

## Description

This function checks whether two curve class representatives C1 and C2 are equivalent.

To do so, it checks whether the vector of intersection numbers with the nonadjacent basis of divisors is the same for C1 and C2.

    i1 : L1={ {{{1,2},{3},{4},{5}},1}, {{{1,3},{2},{4},{5}},1}};

    i2 : C1=curveClassRepresentativeM0nbar(5,L1);

    i3 : L2={ {{{1},{2},{3},{4,5}},-1}, {{{1},{2,5},{3},{4}},1}, {{{1,4},{2},{3},{5}},1},{{{1,3},{2},{4},{5}},1}};

    i4 : C2=curveClassRepresentativeM0nbar(5,L2);

    i5 : isEquivalent(C1,C2)

    o5 = true

## Ways to use isEquivalent:

- `isEquivalent(CurveClassRepresentativeM0nbar,CurveClassRepresentativeM0nbar)`
- isEquivalent(DivisorClassRepresentativeM0nbar,DivisorClassRepresentativeM0nbar) -- check whether two divisor class representatives are numerically equivalent

## For the programmer

The object isEquivalent is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/M0nbar.m2:2214:0.