graph.structure {igraph}R Documentation

Method for structural manipulation of graphs

Description

These are the methods for simple manipulation of graphs: adding and deleting edges and vertices.

Usage

add.edges(graph, edges)
add.vertices(graph, nv)
delete.edges(graph, edges)
delete.vertices(graph, v)

Arguments

graph The graph to work on.
edges Edge sequence, the edges to remove.
nv Numeric constant, the number of vertices to add.
v Vector sequence, the vertices to remove.

Details

add.edges adds the specified edges to the graph. The ids of the vertices are preserved.

add.vertices adds the specified number of isolate vertices to the graph. The ids of the old vertices are preserved.

delete.edges removes the specified edges from the graph. If a specified edge is not present, the function gives an error message, and the original graph remains unchanged. The ids of the vertices are preserved.

delete.vertices removes the specified vertices from the graph together with their adjacent edges. The ids of the vertices are not preserved.

Value

The new graph.

Author(s)

Gabor Csardi csardi@rmki.kfki.hu

Examples

g <- graph.ring(10)
add.edges(g, c(1,5,2,6) )
delete.edges(g, E(g, P=c(0,9, 1,2)) )
delete.vertices(g, c(1,6,7) )

[Package igraph version 0.2.1 Index]