Select edges in a graph
Select edges from a graph object of class dgr_graph.
select_edges( graph, conditions = NULL, set_op = "union", from = NULL, to = NULL, edges = NULL )
graph |
A graph object of class |
conditions |
An option to use filtering conditions for the retrieval of edges. |
set_op |
The set operation to perform upon consecutive selections of
graph nodes. This can either be as a |
from |
An optional vector of node IDs from which the edge is outgoing for filtering the list of edges present in the graph. |
to |
An optional vector of node IDs to which the edge is incoming for filtering the list of edges present in the graph. |
edges |
An optional vector of edge IDs for filtering the list of edges present in the graph. |
A graph object of class dgr_graph.
# Create a node data frame (ndf)
ndf <-
create_node_df(
n = 4,
type = "basic",
label = TRUE,
value = c(3.5, 2.6, 9.4, 2.7))
# Create an edge data frame (edf)
edf <-
create_edge_df(
from = c(1, 2, 3),
to = c(4, 3, 1),
rel = c("a", "z", "a"),
value = c(6.4, 2.9, 5.0))
# Create a graph with the ndf and edf
graph <-
create_graph(
nodes_df = ndf,
edges_df = edf)
# Explicitly select the edge `1`->`4`
graph <-
graph %>%
select_edges(
from = 1,
to = 4)
# Verify that an edge selection has been made
# using the `get_selection()` function
graph %>% get_selection()
# Select edges based on the relationship label
# being `z`
graph <-
graph %>%
clear_selection() %>%
select_edges(
conditions = rel == "z")
# Verify that an edge selection has been made, and
# recall that the `2`->`3` edge uniquely has the
# `z` relationship label
graph %>% get_selection()
# Select edges based on the edge value attribute
# being greater than 3.0 (first clearing the current
# selection of edges)
graph <-
graph %>%
clear_selection() %>%
select_edges(
conditions = value > 3.0)
# Verify that the correct edge selection has been
# made; in this case, edges `1`->`4` and
# `3`->`1` have values for `value` > 3.0
graph %>% get_selection()Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.