In- or out- component of a vertex — subcomponent • igraph

Finds all vertices reachable from a given vertex, or the opposite: all vertices from which a given vertex is reachable via a directed path.

Usage

subcomponent(graph, v, mode = c("all", "out", "in"))

Arguments

graph: The graph to analyze.
v: The vertex to start the search from.
mode: Character string, either “in”, “out” or “all”. If “in” all vertices from which v is reachable are listed. If “out” all vertices reachable from v are returned. If “all” returns the union of these. It is ignored for undirected graphs.

Value

Numeric vector, the ids of the vertices in the same component as v.

Details

A breadth-first search is conducted starting from vertex v.

See also

Other structural.properties: bfs(), component_distribution(), connect(), constraint(), coreness(), degree(), dfs(), distance_table(), edge_density(), feedback_arc_set(), girth(), is_acyclic(), is_dag(), is_matching(), k_shortest_paths(), knn(), reciprocity(), subgraph(), topo_sort(), transitivity(), unfold_tree(), which_multiple(), which_mutual()

Author

Gabor Csardi csardi.gabor@gmail.com

Examples


g <- sample_gnp(100, 1 / 200)
subcomponent(g, 1, "in")
#> + 1/100 vertex, from 440dfdb:
#> [1] 1
subcomponent(g, 1, "out")
#> + 1/100 vertex, from 440dfdb:
#> [1] 1
subcomponent(g, 1, "all")
#> + 1/100 vertex, from 440dfdb:
#> [1] 1