trav_reverse_edge {DiagrammeR} | R Documentation |
From an active selection
of edges in a graph object of class
dgr_graph
, traverse to any
available reverse edges between the
nodes common to the selected edges.
For instance, if an active selection
has the edge 1->2
but there is
also an (unselected) edge 2->1
,
then this function can either switch
to the selection of 2->1
, or,
incorporate both those edges into the
active selection of edges.
trav_reverse_edge(graph, add_to_selection = FALSE)
graph |
a graph object of class
|
add_to_selection |
an option to
either add the reverse edges to the
active selection of edges ( |
a graph object of class
dgr_graph
.
# Create a node data frame (ndf) ndf <- create_node_df( n = 4, type = "basic", label = TRUE) # Create an edge data frame (edf) edf <- create_edge_df( from = c(1, 4, 2, 3, 3), to = c(4, 1, 3, 2, 1)) # Create a graph with the # ndf and edf graph <- create_graph( nodes_df = ndf, edges_df = edf) # Explicitly select the edges # `1`->`4` and `2`->`3` graph <- graph %>% select_edges( from = 1, to = 4) %>% select_edges( from = 2, to = 3) # Get the inital edge selection get_selection(graph) #> [1] 1 3 # Traverse to the reverse edges # (edges `2`: `4`->`1` and # `4`:`3`->`2`) graph <- graph %>% trav_reverse_edge() # Get the current selection of edges get_selection(graph) #> [1] 2 4