Frédéric Chapoton

This may be because the vertex set is build using ``` V := toList(set vertexSet G ** set vertexSet H); ``` Could someone propose another way to build the cartesian...

Still not clear to me what goes wrong. Here is another tentative ``` loadPackage "Graphs";loadPackage "Chordal";loadPackage "NautyGraphs"; C1 = graph({{0,22},{22,1},{1,0}},EntryMode=>"edges"); G1 = cartesianProduct(C1, pathGraph 5); I1 = edgeIdeal G1; N1...

Here is a smaller example, where we can see explicitly that both edge ideals are isomorphic ``` loadPackage "Graphs";loadPackage "Chordal";loadPackage "NautyGraphs"; C1 = graph({{0,22},{22,1},{1,0}},EntryMode=>"edges"); G1 = cartesianProduct(C1, pathGraph 2); I1...

in the previous simplified example, the elim trees look really different.

Here is an even more simplified case ``` loadPackage "Graphs";loadPackage "Chordal";loadPackage "NautyGraphs"; C1 = graph({{0,22},{1,0}},EntryMode=>"edges"); pt = graph({{0,{1}}}); G1 = cartesianProduct(C1, pt); I1 = edgeIdeal G1 N1 = chordalNet(toLex I1);...

Very strangely, the failure depends on the value of the third vertex in C1 ; it fails for 22 and 12, works for -6, 10 and 11 and fails differently...

Do you mean "please show us the results" ? ``` loadPackage "Graphs";loadPackage "Chordal";loadPackage "NautyGraphs"; testtreewidth := n -> ( C1 = graph({{0,n},{1,0}},EntryMode=>"edges"); pt = graph({{0,{1}}}); G1 = cartesianProduct(C1, pt); I1...

This strange behaviour depends on the label in the second factor graph: ``` loadPackage "Graphs";loadPackage "Chordal";loadPackage "NautyGraphs"; testtreewidth := (n, m) -> ( C1 = graph({{0,n},{1,0}},EntryMode=>"edges"); pt = graph({{0,{m}}}); G1...

What would be a short and simple script file to serve as good first testing ground ? Maybe adding a "boolean_expr" would be a good idea ?

my new tentative so far. This manages to parse one-line things, but not serious scripts. Sigh. Not clear to me how to handle the ";". [macaulay2.lark.txt](https://github.com/Macaulay2/M2/files/11869327/macaulay2.lark.txt)