DiagrammeR (version 0.9.2)

get_attr_dfs: Get data frames bound to node attributes

Description

From a graph object of class dgr_graph, get one or more data frames already bound as node and/or edge attribute values given graph node and/or edges.

Usage

get_attr_dfs(graph, node_id = NULL, edge_id = NULL,
  return_format = "single_tbl")

Arguments

graph

a graph object of class dgr_graph.

node_id

a vector of node ID values in which data frames are bound as node attrs.

edge_id

a vector of edge ID values in which data frames are bound as edge attrs.

return_format

the format in which to return the results of several data frames. These can either be: (1) single_tbl (a tibble object resulting from a `bind_rows` operation of multiple data frames), and (2) single_df (a single data frame which all of the data frame data).

Value

either a tibble, a data frame, or a list.

Examples

# NOT RUN {
# 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 = "leading_to")

# Create a graph
graph <-
  create_graph(
    nodes_df = ndf,
    edges_df = edf)

# Create 3 simple data frames to add as
# attributes to nodes/edges
df_1 <-
  data.frame(
    a = c("one", "two"),
    b = c(1, 2),
    stringsAsFactors = FALSE)

df_2 <-
  data.frame(
    a = c("three", "four"),
    b = c(3, 4),
    stringsAsFactors = FALSE)

df_for_edges <-
  data.frame(
    c = c("five", "six"),
    d = c(5, 6),
    stringsAsFactors = FALSE)

# Bind data frames as node attributes
# for nodes `1` and `4`; bind a data
# frame as an edge attribute as well
graph <-
  graph %>%
  set_df_as_node_attr(
    node = 1,
    df = df_1) %>%
  set_df_as_node_attr(
    node = 4,
    df = df_2) %>%
  set_df_as_edge_attr(
    edge = 1,
    df = df_for_edges)

# Get a single tibble by specifying the
# nodes from which there are data frames
# bound as node attributes
get_attr_dfs(
  graph,
  node_id = c(1, 4))
#> # A tibble: 4 x 6
#>   node_edge__    id  type label     a     b
#>         <chr> <int> <chr> <chr> <chr> <dbl>
#> 1        node     1 basic     1   one     1
#> 2        node     1 basic     1   two     2
#> 3        node     4 basic     4 three     3
#> 4        node     4 basic     4  four     4

# You can also get data frames that are
# associated with edges by using the
# same function
get_attr_dfs(
  graph,
  edge_id = 1)
#> # A tibble: 2 x 7
#>   node_edge__    id        rel  from    to     c     d
#>         <chr> <int>      <chr> <int> <int> <chr> <dbl>
#> 1        edge     1 leading_to     1     4  five     5
#> 2        edge     1 leading_to     1     4   six     6

# It's also possible to collect data frames
# associated with both nodes and edges
get_attr_dfs(
  graph,
  node_id = 4,
  edge_id = 1)
#> # A tibble: 4 x 11
#>   node_edge__    id  type label        rel  from    to
#>         <chr> <int> <chr> <chr>      <chr> <int> <int>
#> 1        node     4 basic     4       <NA>    NA    NA
#> 2        node     4 basic     4       <NA>    NA    NA
#> 3        edge     1  <NA>  <NA> leading_to     1     4
#> 4        edge     1  <NA>  <NA> leading_to     1     4
#> # ... with 4 more variables: a <chr>, b <dbl>, c <chr>,
#> #   d <dbl>

# If a data frame is desired instead,
# set `return_format = "single_df"`
get_attr_dfs(
  graph,
  edge_id = 1,
  return_format = "single_df")
#>   node_edge__ id        rel from to    c d
#> 1        edge  1 leading_to    1  4 five 5
#> 2        edge  1 leading_to    1  4  six 6
# }