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Graphs :: reindexBy

reindexBy -- reindexes the vertices according to the input ordering.

Synopsis

Description

This method reindexes the vertices of a specified graph or digraph according to the ordering method entered by the user. The orderings available for graphs are: "maxdegree" (orders the vertices in order of highest to lowest degree), "mindegree" (orders the vertices in order of lowest to highest degree), "random" (orders the vertices randomly), "components" (orders the vertices in the same connected components close together in indices), and "sort" (orders the vertices by sorting their names). For digraphs, the orderings available are: "maxdegreein" (orders the vertices in order of highest in-degree to lowest in-degree), "mindegreein" (orders the vertices in order of lowest in-degree to highest in-degree), "maxdegreeout" (orders the vertices in order of highest out-degree to lowest out-degree), "mindegreeout" (orders the vertices in order of lowest out-degree to highest out-degree), "maxdegree" (orders the vertices in order of highest to lowest degree in the underlying undirected graph), "mindegree" (orders the vertices in order of lowest to highest degree in the underlying undirected graph), "random" (orders the vertices randomly), "sort" (orders the vertices by sorting their names).

i1 : G = graph({1,2,3,4,5},{{1,3},{3,4},{4,5}});
i2 : reindexBy(G,"maxdegree")

o2 = Graph{1 => {3}   }
           2 => {}
           3 => {4, 1}
           4 => {3, 5}
           5 => {4}

o2 : Graph
i3 : D = digraph({1,2,3,4,5},{{1,2},{2,3},{3,1},{4,5},{5,4}})

o3 = Digraph{1 => {2}}
             2 => {3}
             3 => {1}
             4 => {5}
             5 => {4}

o3 : Digraph
i4 : reindexBy(D, "mindegreeout")

o4 = Digraph{1 => {2}}
             2 => {3}
             3 => {1}
             4 => {5}
             5 => {4}

o4 : Digraph

See also

Ways to use reindexBy :

For the programmer

The object reindexBy is a method function.