The eccentricity 
of a graph vertex 
in a connected graph 
is the maximum graph
distance between 
and any other vertex 
of 
.
For a disconnected graph, all vertices are
defined to have infinite eccentricity (West 2000, p. 71).
The maximum eccentricity is the graph diameter. The minimum graph eccentricity is called the graph radius.
For a disconnected graph, the Wolfram Language function VertexEccentricity[g,
v] gives the eccentricity of 
in the connected component
containing 
rather than assigning infinite eccentricity. For a number of named graphs, precomputed
eccentricities that use the infinite-value convention for disconnected graphs can
be obtained using GraphData[graph,
"Eccentricities"].
