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M0nbar :: permute

permute -- compute the image of a curve class representative under a permutation of the marked points

Synopsis

Description

The symmetric group $S_n$ acts on $\bar{M}_{0,n}$ by permuting the marked points.

This function computes the image of a curve class representative $C$ under a permutation $\sigma$ of the marked points.

Enter $\sigma$ as a list $\{ \sigma(1),\sigma(2),\ldots,\sigma(n)\}$. Cycle class notation is not supported for this function.

i1 : L= { {{{2,1},{3},{4},{5}},-2}, {{{1,3},{2},{4},{5}},-7}, {{{1,4},{2},{3},{5}},1}};
i2 : C=curveClassRepresentativeM0nbar(5,L);
i3 : permute({5,2,1,3,4}, C)

o3 = CurveClassRepresentativeM0nbar{CurveExpression => HashTable{{{1, 5}, {2}, {3}, {4}} => -7}}
                                                                 {{1}, {2, 5}, {3}, {4}} => -2
                                                                 {{1}, {2}, {3, 5}, {4}} => 1
                                    NumberOfMarkedPoints => 5

o3 : CurveClassRepresentativeM0nbar

Ways to use permute :

For the programmer

The object permute is a method function.