Filter an edge file to include first-order neighbours of specified nodes

Returns all edges where at least one endpoint is in nodenames, effectively including the nodes themselves and all directly connected neighbours.

Usage

filter.edges.1(nodenames, edge.file)

Arguments

nodenames

Character vector of seed node names.

edge.file

A data frame edge list with node names in columns 1 and 2.

Value

A data frame of edges involving at least one node in nodenames, or NA if no edges remain.