BUILT-IN MATHEMATICA SYMBOL

VertexIndex

gives the integer index for the vertex v in the graph g.

MORE INFORMATION

VertexIndex gives the ordering used in functions such as VertexList, AdjacencyMatrix, KirchhoffMatrix, IncidenceMatrix, and GraphDistanceMatrix.

VertexIndex gives the position for a vertex v in VertexList[g].

VertexIndex gives the row position for a vertex v in IncidenceMatrix[g].

VertexIndex gives the row and column position for a vertex v in AdjacencyMatrix[g], KirchhoffMatrix[g], and GraphDistanceMatrix[g].

EXAMPLES

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Basic Examples (1)

Find the integer index of a vertex:

The index corresponds to the position in the vertex list:

Find the integer index of a vertex:

In[1]:=

Out[1]=

In[2]:=

Out[2]=

The index corresponds to the position in the vertex list:

In[3]:=

Out[3]=

Scope (2)

VertexIndex works with undirected graphs:

Directed graphs:

VertexIndex works with large graphs:

Compare performance with a direct search in VertexList[g]:

Properties & Relations (11)

The VertexIndex of a vertex corresponds to its position in VertexList:

VertexIndex is typically faster than Position:

VertexQ can be used to tell whether VertexIndex will succeed:

Try a vertex item:

Use EdgeIndex to find the integer index of an edge:

VertexIndex gives the row and column ordering used in AdjacencyMatrix:

Test whether

and

are adjacent:

VertexIndex gives the row and column ordering used in WeightedAdjacencyMatrix:

Find the weight of the edge

:

VertexIndex gives the row and column ordering used in AdjacencyMatrix:

Find the shortest distance between

and

:

VertexIndex gives the row and column ordering used in KirchhoffMatrix:

Find the vertex degree of

:

VertexIndex and EdgeIndex give the row and column ordering used in IncidenceMatrix:

Test whether

is incident to

:

VertexIndex gives the ordering of VertexDegree:

Find the vertex degree for 1:

Use VertexDegree directly:

VertexIndex gives the ordering of centralities:

Find centrality measures for 1:

Possible Issues (1)

Some vertices do not seem to have integer indices:

Membership is tested using SameQ rather than Equal:

By using identical expressions the integer index is found: