如何使用 geom_node_circle 动态分配边框颜色？

Question

I'm trying to change the borders of nodes in ggraph using geom_node_circle . I want to set the border colors based on a mapping between the names of the nodes and the colors that I supply for the names. I know that the parameter to change the border is colour .

Make graph for example:

df <- data_frame(group = c("animals","animals","pets","pets","pets","wild animals","wild animals"),
                 subgroup = c("pets","wild animals","rabbit","dog","cat","polar bear","panda bear"))

df <- as.data.frame(table(df))
df <- filter(df, Freq > 0)

vertices <- df %>%
  dplyr::distinct(subgroup, Freq) %>%
  dplyr::add_row(subgroup = "animals", Freq = 0)

graph <- graph_from_data_frame(df, vertices = vertices)

I know how to change all of the borders to a single new color (red):

ggraph(graph, layout = "circlepack", weight = Freq) +
  geom_node_circle(aes(fill =depth),colour = "red") +
  coord_fixed() +
  geom_node_label(aes(label = name), repel = TRUE, size = 5) 

But, I don't know how to assign the border based on the mapping between name in graph and my colors.

Attempt A

Make map and apply to ggraph :

my_colors <- c("black","black","red","black","black","black","black","black")
names(my_colors) <- c("animals","pets","wild animals","rabbit","dog","cat","polar bear","panda bear")

ggraph(graph, layout = "circlepack", weight = Freq) +
  geom_node_circle(aes(fill =depth),colour = my_colors) +
  coord_fixed() +
  geom_node_label(aes(label = name), repel = TRUE, size = 5) 

Returns

Error in `check_aesthetics()`:
! Aesthetics must be either length 1 or the same as the data (2888): colour
Run `rlang::last_error()` to see where the error occurred.

Attempt B

Add color column to original df and apply to ggraph :

df$my_colors <- cbind(df, ifelse(df$subgroup=="wild animals", "red", "black")

ggraph(graph, layout = "circlepack", weight = Freq) +
  geom_node_circle(aes(fill =depth),colour = df$my_colors) +
  coord_fixed() +
  geom_node_label(aes(label = name), repel = TRUE, size = 5) 

Returns the same error as before.

When I look at the graph, I can see that my_colors isn't there:

create_layout(graph, 'circlepack', weight = Freq)

Non-leaf weights ignored
           x          y         r circular  leaf depth         name Freq .ggraph.orig_index .ggraph.index
1  0.0000000  0.0000000 2.3440385    FALSE FALSE     0      animals    0                  8             1
2  0.7244867 -0.8650770 1.2156595    FALSE FALSE     1         pets    1                  4             2
3 -0.7805260  0.9319910 1.1283791    FALSE FALSE     1 wild animals    1                  7             3
4  0.2584208 -0.4098895 0.5641896    FALSE  TRUE     2          cat    1                  1             4
5  1.3517237 -0.6890459 0.5641896    FALSE  TRUE     2          dog    1                  2             5
6 -0.5085709  0.4376730 0.5641896    FALSE  TRUE     2   panda bear    1                  3             6
7 -1.0524811  1.4263089 0.5641896    FALSE  TRUE     2   polar bear    1                  5             7
8  0.5633157 -1.4962957 0.5641896    FALSE  TRUE     2       rabbit    1                  6             8

Attempt C

Try adding my_color to vertices :

vertices$my_color <- ifelse(vertices$subgroup=="wild animals", "red", "black")

graph <- graph_from_data_frame(df, vertices = vertices)

# check if my_color is there
create_layout(graph, 'circlepack', weight = Freq)

I can see my_color is now in graph :

Non-leaf weights ignored
            x          y         r circular  leaf depth         name Freq my_color .ggraph.orig_index .ggraph.index
1  0.00000000  0.0000000 2.3440387    FALSE FALSE     0      animals    0    black                  8             1
2  0.42321874  1.0460045 1.2156596    FALSE FALSE     1         pets    1    black                  4             2
3 -0.45595483 -1.1269132 1.1283791    FALSE FALSE     1 wild animals    1      red                  7             3
4  1.05259805  1.2142151 0.5641896    FALSE  TRUE     2          cat    1    black                  1             4
5  0.25420381  0.4168406 0.5641896    FALSE  TRUE     2          dog    1    black                  2             5
6 -0.05740794 -0.7275760 0.5641896    FALSE  TRUE     2   panda bear    1    black                  3             6
7 -0.85450171 -1.5262505 0.5641896    FALSE  TRUE     2   polar bear    1    black                  5             7
8 -0.03714565  1.5069576 0.5641896    FALSE  TRUE     2       rabbit    1    black                  6             8

But if I run

ggraph(graph, layout = "circlepack", weight = Freq) +
  geom_node_circle(aes(fill =depth),colour = my_color) +
  coord_fixed() +
  geom_node_label(aes(label = name), repel = TRUE, size = 5)

I get

Error in layer(data = data, mapping = mapping, stat = StatNodeCircle,  : 
  object 'my_color' not found

So, then I figured that I just don't know how to access attributes from graph but I figured that out and assigned it to the border color using colour = V(graph)$my_color . That still results in the same error indicating that the length of data is 2888. I assume that this error is being thrown because my list of colors is less than that.

Thoughts

I'm new to using ggraph , and I think that I'm lacking some fundamental knowledge to figure this out....

Solution

Modified from @DanAdams original answer:

df <- data_frame(group = c("animals","animals","pets","pets","pets","wild animals","wild animals"),
                 subgroup = c("pets","wild animals","rabbit","dog","cat","polar bear","panda bear"))

df <- as.data.frame(table(df))
df <- filter(df, Freq > 0)

vertices <- df %>%
  dplyr::distinct(subgroup, Freq) %>%
  dplyr::add_row(subgroup = "animals", Freq = 0)

vertices$my_color <- ifelse(vertices$subgroup=="wild animals", "red", "black")

graph <- graph_from_data_frame(df, vertices = vertices)

ggraph(graph, layout = "circlepack", weight = Freq) +
  geom_node_circle(aes(fill =depth,colour = my_color)) +
  coord_fixed() +
  geom_node_label(aes(label = name), repel = TRUE, size = 5)

Answer 1

It seems you just need to add color = name inside of the aes() .

I also colored the labels to match to make it easier to follow.

library(tidyverse)
library(igraph)
library(ggraph)

df <- data_frame(group = c("animals","animals","pets","pets","pets","wild animals","wild animals"),
                 subgroup = c("pets","wild animals","rabbit","dog","cat","polar bear","panda bear"))

my_colors <- c("black","black","red","black","black","black","black","black")
names(my_colors) <- c("animals","pets","wild animals","rabbit","dog","cat","polar bear","panda bear")

df <- as.data.frame(table(df))
df <- filter(df, Freq > 0)

vertices <- df %>%
  dplyr::distinct(subgroup, Freq) %>%
  dplyr::add_row(subgroup = "animals", Freq = 0)

graph <- graph_from_data_frame(df, vertices = vertices)

ggraph(graph, layout = "circlepack", weight = Freq) +
  geom_node_circle(aes(fill = depth, color = name), size = 1) +
  coord_fixed() +
  geom_node_label(aes(label = name, color = name), repel = TRUE, size = 5, show.legend = F) +
  scale_color_manual(values = my_colors)

^{Created on 2022-09-22 by the reprex package (v2.0.1)}