This function returns the index of the edge of the (hyper)graph, where the ordering is determined by the internal ordering of the edges. Note that the internal order of the edges may not be preserved by methods that change the hypergraph (i.e., inducedHyperGraph, changeRing, hyperGraph(MonomialIdeal), etc.).
i1 : S = QQ[z_1..z_8]; |
i2 : h = hyperGraph {z_2*z_3*z_4,z_6*z_8,z_7*z_5,z_1*z_6*z_7,z_2*z_4*z_8}
o2 = HyperGraph{edges => {{z , z , z }, {z , z }, {z , z , z }, {z , z , z }, {z , z }}}
2 3 4 5 7 1 6 7 2 4 8 6 8
ring => S
vertices => {z , z , z , z , z , z , z , z }
1 2 3 4 5 6 7 8
o2 : HyperGraph
|
i3 : edges h
o3 = {{z , z , z }, {z , z }, {z , z , z }, {z , z , z }, {z , z }}
2 3 4 5 7 1 6 7 2 4 8 6 8
o3 : List
|
i4 : getEdgeIndex (h,{z_2,z_4,z_8}) -- although entered last, edge is internally stored in 4th spot (counting begins at 0)
o4 = 3
|
i5 : getEdge(h,3)
o5 = {z , z , z }
2 4 8
o5 : List
|
i6 : getEdgeIndex (h,{z_1,z_2}) -- not in the edge list
o6 = -1
|
The object getEdgeIndex is a method function.