如何整齐地对齐堆叠的条形图标签，条形图的每一侧都有不同的对齐方式？

Question

我的标签与堆叠条形图的每一侧大致对齐。问题是它们看起来像一团糟，因为它们在栏的两边都不是左右对齐的。我该如何解决这个问题，让他们看起来很专业？

df3 <- data.frame(
  Label = c("Dasher", "Dancer", "Comet", "Cupid", "Prancer", "Blitzen", "Rudolph"),
  Amount = c(650.01, 601.01, 340.05, 330.20, 260.01, 250.80, 10.10)
)

# Sort order
level_order <- df3 %>% 
  arrange(desc(Amount))

ggplot(level_order, aes(fill=fct_inorder(Label), y=Amount, x="")) + 
               geom_bar(position="stack", stat="identity", width = 0.55) +
               scale_fill_brewer(palette = "Blues", direction = -1) +
               theme_void() +
               geom_text(aes(label = paste0("$", Amount)),
                         position = position_stack(vjust = 0.5),
                         hjust = -3.1,
                         size = 5) +
               geom_text(aes(label = Label),
                         position = position_stack(vjust = 0.5),
                         hjust = 5,
                         size = 5) +
               theme(legend.position = "none") +
               theme(plot.title = element_text(size = 50, hjust = .5, vjust = 0)) +
               ggtitle("Food Costs by Reindeer")

Answer 1

hjust 确定文本对齐方式（0 为左对齐，1 为右对齐）。此时你的geom_text 的 x 坐标默认为 1，因此更改它会更改文本的位置。

ggplot(level_order, aes(fill=fct_inorder(Label), y=Amount, x="")) + 
  geom_bar(position="stack", stat="identity", width = 0.55) +
  scale_fill_brewer(palette = "Blues", direction = -1) +
  theme_void() +
  geom_text(aes(x=0.6, label = paste0("$", Amount)),
            position = position_stack(vjust = 0.5),
            hjust = 0.5,
            size = 5) +
  geom_text(aes(x=1.4, label = Label),
            position = position_stack(vjust = 0.5),
            hjust = 0.5,
            size = 5) +
  theme(legend.position = "none") +
  theme(plot.title = element_text(size = 50, hjust = .5, vjust = 0)) +
  ggtitle("Food Costs by Reindeer")

Answer 2

尝试在对geom_text 的调用中修复x 坐标并管理与hjust 的对齐...

df3 <- data.frame(
  Label = c("Dasher", "Dancer", "Comet", "Cupid", "Prancer", "Blitzen", "Rudolph"),
  Amount = c(650.01, 601.01, 340.05, 330.20, 260.01, 250.80, 10.10)
)


library(ggplot2)
library(dplyr)
library(forcats)

level_order <- df3 %>% 
  arrange(desc(Amount))

ggplot(level_order, aes(fill=fct_inorder(Label), y=Amount, x="")) + 
  geom_bar(position="stack", stat="identity", width = 0.55) +
  scale_fill_brewer(palette = "Blues", direction = -1) +
  theme_void() +
  geom_text(aes(x = 1.3, label = paste0("$", Amount)),
            position = position_stack(vjust = 0.5),
            hjust = 0,
            size = 5) +
  geom_text(aes(x = 0.6, label = Label),
            position = position_stack(vjust = 0.5),
            hjust = 0,
            size = 5) +
  theme(legend.position = "none") +
  theme(plot.title = element_text(size = 50, hjust = .5, vjust = 0)) +
  ggtitle("Food Costs by Reindeer")

^{由reprex package (v2.0.1) 于 2021-12-19 创建}

Answer 3

你也可以把 hjust 作为一种审美。为此，您需要将标签准备为单独的数据框。然后，您只需调用geom_text一次。我并不是说这一定更好，只是指出这是可能的。代码中还有一些 cmets，以及一些常见的陷阱。

library(tidyverse)
df3 <- data.frame(
  Label = c("Dasher", "Dancer", "Comet", "Cupid", "Prancer", "Blitzen", "Rudolph"),
  Amount = c(650.01, 601.01, 340.05, 330.20, 260.01, 250.80, 10.10)
) %>% 
  ## arrange step here
  arrange(desc(Amount)) 

## I like to prepare the data outside ggplot
label_df <- df3 %>% 
  mutate(Amount_lab = paste0("$", Amount)) %>%
  pivot_longer(-Amount) %>%
## this adds a column for your adjustment, and the x position compared with the central column
  mutate(hjust = rep(0:1, nrow(.)/2), 
         x = rep(c(1.21, .79), nrow(.)/2))

ggplot(mapping = aes(y = Amount)) + 
  ## geom_col is geom_bar(stat = "identity"), stack is default, so you can omit it
  ## call data in the geom layers
  ## set x to 1
  ## width = .4 so it matches your selected x from above
  geom_col(data = df3, aes(x = 1, fill=fct_inorder(Label)), width = .4) +
  scale_fill_brewer(palette = "Blues", direction = -1) +
  ## need to reverse both y and value, weirdly 
  geom_text(data = label_df, aes(x, y = rev(Amount), label = rev(value), 
## this is the main trick
  hjust = hjust),
  position = position_stack(vjust = 0.5) ) +
  ## sadly, need to turn clip off
  coord_cartesian(clip = "off") +
  theme_void() +
## call theme only once!!
  theme(legend.position = "none",
        plot.title = element_text(size = 20, hjust = .5, vjust = 0),
        ## you need to add a margin 
        plot.margin = margin(r = .6, l = .6, unit = "in")) +
  ggtitle("Food Costs by Reindeer")

^{由reprex package (v2.0.1) 于 2021-12-20 创建}

Answer 4

使用上面彼得的回答（提醒我我忘记存在的“x”位置参数），这是得到我想要的最终修复。 hjust = 0 是左对齐，hjust = 1 是右对齐。

library(tidyverse)
library(grid)

df3 <- data.frame(
  Label = c("Dasher", "Dancer", "Comet", "Cupid", "Prancer", "Blitzen", "Rudolph"),
  Amount = c(650.01, 601.01, 340.05, 330.20, 260.01, 250.80, 10.10)
)

# Sort order
level_order <- df3 %>% 
  arrange(desc(Amount))

ggplot(level_order, aes(fill=fct_inorder(Label), y=Amount, x="")) + 
               geom_bar(position="stack", stat="identity", width = 0.55) +
               scale_fill_brewer(palette = "Blues", direction = -1) +
               theme_void() +
               geom_text(aes(x = 1.3, label = paste0("$", Amount)),
                         position = position_stack(vjust = 0.5),
                         hjust = 0,
                         size = 5) +
               geom_text(aes(x = 0.7, label = Label),
                         position = position_stack(vjust = 0.5),
                         hjust = 1,
                         size = 5) +
               theme(legend.position = "none",
                     plot.margin = unit(c(0,0,2,0), "cm"))
grid.text("Food Costs by Reindeer", x = unit(0.5, "npc"), y = unit(0, "npc"),
          vjust = -0.5, gp = gpar(cex=4))