node_type {DiagrammeR} | R Documentation |
From a graph object of class
dgr_graph
, query a node in the graph (using
the node ID) and perform operations on the type
definition for that node.
node_type(graph, node, action = "read", value = NULL)
graph |
a graph object of class
|
node |
a node ID corresponding to the node to be selected. |
action |
the operation to perform on the node's
type attribute. To remove the type definition from a
node, use either |
value |
a string denoting the node type, to be supplied when either adding or updating a node type definition. |
a graph object of class dgr_graph
.
library(magrittr) # Create a node data frame (ndf) nodes <- create_nodes( nodes = 1:5, type = c("a", "b", "c", "a", "c")) # Create an edge data frame (edf) edges <- create_edges( from = c(1, 3, 5, 2, 4), to = c(2, 2, 4, 4, 3)) # Create a graph graph <- create_graph(nodes_df = nodes, edges_df = edges) # Read the node `type` for node `1` graph %>% node_type(1) #> [1] "a" # Remove the `type` value entirely from # node `1` graph %<>% node_type(1, "delete") # Check that node `1` no longer has a # `type` assignment graph %>% node_type(1, "check") #> [1] FALSE # Add the `type` value "b" to node `1` graph %<>% node_type(1, "add", "b") # Read the node `type` for node `1` graph %>% node_type(1) #> [1] "b" # Perform an in-place update of the `type` # value for node `1` ("b" to "a") graph %<>% node_type(1, "update", "a") # Read the node `type` for node `1` to ensure # that the change was made graph %>% node_type(1) #> [1] "a"