This function writes a curve class in the singleton spine basis of curves. The input is the number of marked points n, and a list of the intersection numbers with the nonadjacent basis of divisors.
Recall that the singleton spine basis of curves is only defined on $\bar{M}_{0,n}$ if $n \geq 7$.
i1 : L= { {{1,2},{3,4},{5,6},{7,8}}=>1 }; |
i2 : C=curveClassRepresentativeM0nbar(8,L); |
i3 : v=writeCurveInDualNonadjacentBasis(C); |
i4 : writeCurveInSingletonSpineBasis(8,v) o4 = CurveClassRepresentativeM0nbar{CurveExpression => HashTable{{{1, 2}, {3, 4}, {5}, {6, 7, 8}} => 1 }} {{1, 3, 4, 5, 6}, {2}, {7}, {8}} => -1 {{1, 3, 4, 5, 8}, {2}, {6}, {7}} => 1 {{1, 3, 4, 7, 8}, {2}, {5}, {6}} => -1 {{1, 8}, {2}, {3, 4, 5}, {6, 7}} => 1 {{1}, {2, 3, 4, 5}, {6}, {7, 8}} => 1 {{1}, {2, 3, 4, 7, 8}, {5}, {6}} => -1 {{1}, {2}, {3, 4, 5, 6, 7}, {8}} => 1 {{1}, {2}, {3, 4, 5, 6}, {7, 8}} => -1 {{1}, {2}, {3, 4, 6, 7, 8}, {5}} => 1 {{1}, {2}, {3, 4, 7, 8}, {5, 6}} => -1 NumberOfMarkedPoints => 8 o4 : CurveClassRepresentativeM0nbar |