SzegedIndex
The sum over the edges of the vertices nearer one end times those nearer the other.
✓ checked against that system · ! checked, with disagreements (hover a chip)FindStat
St000263via LabeledGraph✓SzegedIndex(graph)The sum over the edges of the vertices nearer one end times those nearer the other.Typed signatures
| Type | Package | Applies |
|---|---|---|
(labeled_graph) -> number | combinatorics | always |
Details
- Defined over
LabeledGraphas an expression in_x, evaluated by compute-engine — the definition IS the implementation. - Takes a
LabeledGraphand nothing else — it reads values against their positions, or walks the orbits, so it needs the bijection. Applying it to a bare list is a type error, not a wrong answer. - FindStat's St000263. A vertex in another component is as far from both ends, so is in neither count. The graph with no vertices gives 0.
Definition
Epsil, as the implementation runs it.
on LabeledGraph, over _x
0 if _x[1] == 0 else Apply((n: integer) => Apply((edges: list<list<integer>>) => Apply(
(adjacency: list<list<integer>>) => Apply(
(distances: list<list<integer>>) => Max(Sum(Map(Function(Max(Sum(Map(Function(1 if distances[e[1]][w] < distances[e[2]][w] else 0, w), Range(1, n))), 0) *
Max(Sum(Map(Function(1 if distances[e[2]][w] < distances[e[1]][w] else 0, w), Range(1, n))), 0), e), edges)), 0),
Apply((matrix: list<list<integer>>) => Apply(
(a_init: list<list<integer>>) => Fold((a: list<list<integer>>, k) => Apply(
(a_next: list<list<integer>>) => a_next,
Map(Function(Map(Function(Min(a[i][j], a[i][k] + a[k][j]), j), Range(1, n)), i), Range(1, n)),
), a_init, Range(1, n)),
Map(
Function(Map(Function(0 if i == j else 1 if matrix[i][j] == 1 else 2n, j), Range(1, n)), i),
Range(1, n),
),
), adjacency),
),
Map(Function(Map(
Function(Max(Sum(Map(Function((1 if e[1] == i else 0) *
(1 if e[2] == j else 0) +
(1 if e[1] == j else 0) *
(1 if e[2] == i else 0), e), edges)), 0), j),
Range(1, n),
), i), Range(1, n)),
), _x[2]), _x[1])Examples
Properties #
About
| Examples | 4 |
|---|---|
| Crosswalk | FindStat |