DiagrammeR (version 0.9.2)

recode_edge_attrs: Recode a set of edge attribute values

Description

Within a graph's internal edge data frame (edf), recode character or numeric edge attribute values. Optionally, one can specify a replacement value for any unmatched mappings.

Usage

recode_edge_attrs(graph, edge_attr_from, ..., otherwise = NULL,
  edge_attr_to = NULL)

Arguments

graph

a graph object of class dgr_graph.

edge_attr_from

the name of the edge attribute column from which values will be recoded.

...

single-length character vectors with the recoding instructions. The first component should have the value to replace and the second should have the replacement value (in the form "[to_replace] -> [replacement]", ...).

otherwise

an optional single value for recoding any unmatched values.

edge_attr_to

an optional name of a new edge attribute to which the recoded values will be applied. This will retain the original edge attribute and its values.

Value

a graph object of class dgr_graph.

Examples

# NOT RUN {
# Create a random graph
graph <-
  create_random_graph(
    n = 4, m = 6,
    set_seed = 23) %>%
  set_edge_attrs(
    edge_attr = rel,
    values = c("a", "b", "a",
               "c", "b", "d"))

# Get the graph's internal edf to show which
# edge attributes are available
get_edge_df(graph)
#>   id from to rel
#> 1  1    2  4   a
#> 2  2    1  4   b
#> 3  3    2  3   a
#> 4  4    3  4   c
#> 5  5    1  3   b
#> 6  6    1  2   d

# Recode the `rel` node attribute, creating a
# new edge attribute called `penwidth`; here,
# `a` is recoded to `1.0`, `b` maps to `1.5`, and
# all other values become `0.5`
graph <-
  graph %>%
  recode_edge_attrs(
    edge_attr_from = rel,
    "a -> 1.0",
    "b -> 1.5",
    otherwise = 0.5,
    edge_attr_to = penwidth)

# Get the graph's internal edf to show that the
# node attribute values had been recoded and
# copied into a new node attribute
get_edge_df(graph)
#>   id from to rel penwidth
#> 1  1    2  4   a      1.0
#> 2  2    1  4   b      1.5
#> 3  3    2  3   a      1.0
#> 4  4    3  4   c      0.5
#> 5  5    1  3   b      1.5
#> 6  6    1  2   d      0.5
# }