In geom_text() how to shirnk text label size and not lost mapping attributes-CodePudding

In below code, I add text to plot using geom_text() and mapping value to the size. But the label size is a little big compare to plot, How to shrink all of them to little size ? (and not lost the mapping attributes).Thanks!

library(tidyverse)
plot_data <- data.frame(category=c('A','A','B','C'),
                        sub_category=c('a1','a2','b1','c1'),
                        value=c(6,12,3,2))

plot_data %>% mutate(sub_category=if_else(category=='A',
                                          sub_category,category)) %>% 
  pivot_longer(names_to = 'title',values_to ='cat_region',-value) %>% 
  filter(!(title=='sub_category'&cat_region %in% c('B','C') )) %>% 
  group_by(title,cat_region) %>% 
  summarise(value_sum=sum(value)) %>% 
  ggplot(aes(x=title,y=value_sum,fill=cat_region,
             group=interaction(title,cat_region))) geom_col() 
  geom_text(position=position_stack(0.5),
            aes(size=value_sum,
                label=paste0(cat_region,'\n',value_sum))) 
  scale_x_discrete(
  limits=c('blank','blank','blank','category','sub_category')) 
  coord_polar(theta='y')

CodePudding user response：

As with other aesthetics you could set the range of possible values via the scale, e.g. in case of the size aesthetic via the range argument of scale_size. By reducing the maximum value for the range you could shrink all labels.

library(tidyverse)

plot_data %>%
  mutate(sub_category = if_else(category == "A",
    sub_category, category
  )) %>%
  pivot_longer(names_to = "title", values_to = "cat_region", -value) %>%
  filter(!(title == "sub_category" & cat_region %in% c("B", "C"))) %>%
  group_by(title, cat_region) %>%
  summarise(value_sum = sum(value)) %>%
  ggplot(aes(
    x = title, y = value_sum, fill = cat_region,
    group = interaction(title, cat_region)
  ))  
  geom_col()  
  geom_text(position=position_stack(0.5),
    aes(
      size = value_sum,
      label = paste0(cat_region, "\n", value_sum)
    )
  )  
  scale_x_discrete(
    limits = c("blank", "blank", "blank", "category", "sub_category")
  )  
  scale_size(range = c(1, 3.5))  
  coord_polar(theta = "y")
#> `summarise()` has grouped output by 'title'. You can override using the
#> `.groups` argument.