ggplot y-axis labels should be in alphabetical order when values are tied-CodePudding

I have a similar question to

set.seed(123)

df <- data.frame(
  species = LETTERS[seq(from = 1, to = 5)],
  sal = round(rnorm(n = 5, mean = 27, sd = .01), 2),
  num = sample(x = 1:20, size = 20, replace = F)
)

pivot_df <- df %>%
  group_by(species) %>%
  summarize(n = n(), median_sal = median(sal, na.rm = T)) %>%
  arrange(median_sal)

ggplot(
  data = subset(df, !is.na(sal)),
  aes(y = reorder(species, -sal, FUN = median), x = sal)
)  
  geom_boxplot(outlier.shape = 1, outlier.size = 1, orientation = "y")  
  coord_cartesian(clip = "off")  
  annotation_custom(grid::textGrob(pivot_df$n,
    x = 1.035,
    y = c(0.89, 0.70, 0.51, 0.32, 0.13),
    gp = grid::gpar(cex = 0.6)
  ))  
  annotation_custom(grid::textGrob(expression(bold(underline("N"))),
    x = 1.035,
    y = 1.02,
    gp = grid::gpar(cex = 0.7)
  ))  
  ylab("")   xlab("")  
  theme(
    axis.text.y = element_text(size = 7, face = "italic"),
    axis.text.x = element_text(size = 7),
    axis.title.x = element_text(size = 9, face = "bold"),
    axis.line = element_line(colour = "black"),
    panel.background = element_blank(),
    panel.grid.minor = element_blank(),
    panel.border = element_rect(colour = "black", fill = NA, size = 1),
    panel.grid.major = element_line(colour = "#E0E0E0"),
    plot.title = element_text(hjust = 0.5),
    plot.margin = margin(21, 40, 20, 20))

CodePudding user response：

One option would be to set the order of species according to the order in your pivot_df instead of using reorder. To this end I first convert pivot_df$species to a factor using forcats::fct_inorder(species). Afterwards I convert df$species to a factor using factor(species, levels = rev(levels(pivot_df$species)):

library(dplyr)
library(ggplot2)

pivot_df <- df %>%
  group_by(species) %>%
  summarize(n = n(), median_sal = median(sal, na.rm = T)) %>%
  arrange(median_sal) |> 
  mutate(species = forcats::fct_inorder(species))

ggplot(
  data = subset(df, !is.na(sal)),
  aes(y = factor(species, levels = rev(levels(pivot_df$species))), x = sal)
)  
  geom_boxplot(outlier.shape = 1, outlier.size = 1, orientation = "y")  
  coord_cartesian(clip = "off")  
  annotation_custom(grid::textGrob(pivot_df$n,
    x = 1.035,
    y = c(0.89, 0.70, 0.51, 0.32, 0.13),
    gp = grid::gpar(cex = 0.6)
  ))  
  annotation_custom(grid::textGrob(expression(bold(underline("N"))),
    x = 1.035,
    y = 1.02,
    gp = grid::gpar(cex = 0.7)
  ))  
  ylab("")   xlab("")  
  theme(
    axis.text.y = element_text(size = 7, face = "italic"),
    axis.text.x = element_text(size = 7),
    axis.title.x = element_text(size = 9, face = "bold"),
    axis.line = element_line(colour = "black"),
    panel.background = element_blank(),
    panel.grid.minor = element_blank(),
    panel.border = element_rect(colour = "black", fill = NA, size = 1),
    panel.grid.major = element_line(colour = "#E0E0E0"),
    plot.title = element_text(hjust = 0.5),
    plot.margin = margin(21, 40, 20, 20))