geom_edge_*
functions. A connection does not need to only be
defined by a start and end node, but can include intermediary nodes.
get_con
helps in creating connection data by letting you specify start
and end node and automatically find the shortest path within the graph
structure that connects the given points. If this is not what is needed it is
also possible to supply a list of vectors giving node indexes that defines a
connection.
get_con(from = integer(), to = integer(), paths = NULL, ...)
get_edges
,
get_nodes