DiagrammeR (version 1.0.11)

rescale_edge_attrs: Rescale numeric edge attribute values

Description

From a graph object of class dgr_graph, take a set of numeric values for an edge attribute, rescale to a new numeric or color range, then write to the same edge attribute or to a new edge attribute column.

Usage

rescale_edge_attrs(
  graph,
  edge_attr_from,
  to_lower_bound = 0,
  to_upper_bound = 1,
  edge_attr_to = NULL,
  from_lower_bound = NULL,
  from_upper_bound = NULL
)

Value

A graph object of class dgr_graph.

Arguments

graph

A graph object of class dgr_graph.

edge_attr_from

The edge attribute containing numeric data that is to be rescaled to new numeric or color values.

to_lower_bound

The lower bound value for the set of rescaled values. This can be a numeric value or an X11 color name.

to_upper_bound

The upper bound value for the set of rescaled values. This can be a numeric value or an X11 color name.

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.

from_lower_bound

An optional, manually set lower bound value for the rescaled values. If not set, the minimum value from the set will be used.

from_upper_bound

An optional, manually set upper bound value for the rescaled values. If not set, the minimum value from the set will be used.

See Also

Other edge creation and removal: add_edge(), add_edge_clone(), add_edge_df(), add_edges_from_table(), add_edges_w_string(), add_forward_edges_ws(), add_reverse_edges_ws(), copy_edge_attrs(), create_edge_df(), delete_edge(), delete_edges_ws(), delete_loop_edges_ws(), drop_edge_attrs(), edge_data(), join_edge_attrs(), mutate_edge_attrs(), mutate_edge_attrs_ws(), recode_edge_attrs(), rename_edge_attrs(), rev_edge_dir(), rev_edge_dir_ws(), set_edge_attr_to_display(), set_edge_attrs(), set_edge_attrs_ws()

Examples

# Create a random graph using the
# `add_gnm_graph()` function
graph <-
  create_graph() %>%
  add_gnm_graph(
    n = 10,
    m = 7,
    set_seed = 23) %>%
  set_edge_attrs(
    edge_attr = weight,
    values = rnorm(
      n = count_edges(.),
      mean = 5,
      sd = 1))

# Get the graph's internal edf
# to show which edge attributes
# are available
graph %>% get_edge_df()

# Rescale the `weight` edge
# attribute, so that its values
# are rescaled between 0 and 1
graph <-
  graph %>%
  rescale_edge_attrs(
    edge_attr_from = weight,
    to_lower_bound = 0,
    to_upper_bound = 1)

# Get the graph's internal edf
# to show that the edge attribute
# values had been rescaled
graph %>% get_edge_df()

# Scale the values in the `weight`
# edge attribute to different
# shades of gray for the `color`
# edge attribute and different
# numerical values for the
# `penwidth` attribute
graph <-
  graph %>%
  rescale_edge_attrs(
    edge_attr_from = weight,
    to_lower_bound = "gray80",
    to_upper_bound = "gray20",
    edge_attr_to = color) %>%
  rescale_edge_attrs(
    edge_attr_from = weight,
    to_lower_bound = 0.5,
    to_upper_bound = 3,
    edge_attr_to = penwidth)

# Get the graph's internal edf
# once more to show that scaled
# grayscale colors are now available
# in `color` and scaled numerical
# values are in the `penwidth`
# edge attribute
graph %>% get_edge_df()