Join new node attribute values using a data frame

Join new node attribute values in a left join using a data frame. The use of a left join in this function allows for no possibility that nodes in the graph might be removed after the join.

Usage

join_node_attrs(graph, df, by_graph = NULL, by_df = NULL)

Arguments

graph

A graph object of class dgr_graph.

df

The data frame to use for joining.

by_graph

Optional specification of the column in the graph's internal node data frame for the left join. If both by_graph and by_df are not provided, then a natural join will occur if there are columns in the graph's ndf and in df with identical names.

by_df

Optional specification of the column in df for the left join. If both by_graph and by_df are not provided, then a natural join will occur if there are columns in the graph's ndf and in df with identical names.

Value

A graph object of class dgr_graph.

See also

Other node creation and removal: add_n_node_clones(), add_n_nodes(), add_n_nodes_ws(), add_node(), add_node_clones_ws(), add_node_df(), add_nodes_from_df_cols(), add_nodes_from_table(), colorize_node_attrs(), copy_node_attrs(), create_node_df(), delete_node(), delete_nodes_ws(), drop_node_attrs(), layout_nodes_w_string(), mutate_node_attrs(), mutate_node_attrs_ws(), node_data(), recode_node_attrs(), rename_node_attrs(), rescale_node_attrs(), set_node_attr_to_display(), set_node_attr_w_fcn(), set_node_attrs(), set_node_attrs_ws(), set_node_position()

Examples

# Set a seed
suppressWarnings(RNGversion("3.5.0"))
set.seed(23)

# Create a simple graph
graph <-
  create_graph() %>%
  add_n_nodes(n = 5) %>%
  add_edges_w_string(
    edges = "1->2 1->3 2->4 2->5 3->5")

# Create a data frame with node ID values and a
# set of numeric values
df <-
  data.frame(
    values = round(rnorm(6, 5), 2),
    id = 1:6)

# Join the values in the data frame to the
# graph's nodes; this works as a left join using
# identically-named columns in the graph and the df
# (in this case the `id` column is common to both)
graph <-
  graph %>%
  join_node_attrs(
    df = df)

# Get the graph's internal ndf to show that the
# join has been made
graph %>% get_node_df()
#>   id type label values
#> 1  1 <NA>  <NA>   6.00
#> 2  2 <NA>  <NA>   6.11
#> 3  3 <NA>  <NA>   4.72
#> 4  4 <NA>  <NA>   6.02
#> 5  5 <NA>  <NA>   5.05

# Get betweenness values for each node and
# add them as a node attribute (Note the
# common column name `id` in the different
# tables results in a natural join)
graph <-
  graph %>%
  join_node_attrs(
    df = get_betweenness(.))

# Get the graph's internal ndf to show that
# this join has been made
graph %>% get_node_df()
#>   id type label values betweenness
#> 1  1 <NA>  <NA>   6.00         0.0
#> 2  2 <NA>  <NA>   6.11         1.5
#> 3  3 <NA>  <NA>   4.72         0.5
#> 4  4 <NA>  <NA>   6.02         0.0
#> 5  5 <NA>  <NA>   5.05         0.0