Depth-first search

graph.dfs() was renamed to dfs() to create a more consistent API.

Usage

graph.dfs(
  graph,
  root,
  mode = c("out", "in", "all", "total"),
  unreachable = TRUE,
  order = TRUE,
  order.out = FALSE,
  father = FALSE,
  dist = FALSE,
  in.callback = NULL,
  out.callback = NULL,
  extra = NULL,
  rho = parent.frame(),
  neimode
)

Arguments

graph

The input graph.

root

The single root vertex to start the search from.

mode

For directed graphs specifies the type of edges to follow. ‘out’ follows outgoing, ‘in’ incoming edges. ‘all’ ignores edge directions completely. ‘total’ is a synonym for ‘all’. This argument is ignored for undirected graphs.

unreachable

Logical, whether the search should visit the vertices that are unreachable from the given root vertex (or vertices). If TRUE, then additional searches are performed until all vertices are visited.

order

Logical, whether to return the DFS ordering of the vertices.

order.out

Logical, whether to return the ordering based on leaving the subtree of the vertex.

father

Logical, whether to return the father of the vertices.

dist

Logical, whether to return the distance from the root of the search tree.

in.callback

Callback function. This is called whenever a vertex is visited. See details below. Default: NULL.

out.callback

Callback function. This is called whenever the subtree of a vertex is completed by the algorithm. See details below. Default: NULL.

extra

Additional argument to supply to the callback function.

rho

The environment in which the callback function is evaluated.

neimode

This argument is deprecated from igraph 1.3.0; use mode instead.

Related documentation in the C library

vcount()