當值綁定時，ggplot y 軸標簽應按字母順序排列

Question

我有一個與這篇文章類似的問題，但我想知道是否有可能兩者都1.保持我的 y 軸值相同的順序，從最低到最高 -> aes(y = reorder(species, -sal, FUN = median), x = sal))和2.在值綁定時更改 y 軸標簽的默認順序； 此解決方案不能解決問題： scale_y_discrete(limits=rev) 。 目前，如果值是綁定的，則 y 軸標簽 go 以相反的字母順序排列。 這通常不會有問題，但我希望標簽與相應的樣本大小注釋相匹配。 當值綁定時，這會混淆標簽的正確順序。 每個 y 軸的樣本大小 label 在我的真實 dataframe 中有很大不同，我只是不知道如何在示例 df 中更改它。

“E”和“D”不再按字母順序排列，值是綁定的。 當值綁定時，順序應為 A、B、D、E、C（如 pivot 表）。

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))

Answer 1

一種選擇是根據pivot_df中的順序設置species順序，而不是使用reorder 。 為此，我首先使用forcats::fct_inorder(species)將pivot_df$species轉換為一個factor 。 之后，我使用factor(species, levels = rev(levels(pivot_df$species))將df$species轉換為一個因子：

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))