如何解决Lollipop Plot（棒棒糖图）标签重叠、可读性差的问题？

当数据量较大时，棒棒糖图的标签容易出现重叠问题，以下是几个实用的解决办法：

1. 用ggrepel包自动避让标签 #

这是最省心的方案，ggrepel包的geom_text_repel会自动调整标签位置，避免重叠。

# 首次使用先安装包
install.packages("ggrepel")
library(ggplot2)
library(ggrepel)

df <- read.table(file = '24 hpi MP BP.tsv', sep = '\t', header = TRUE)
data <- data.frame(
  x = df$Name,
  y = df$Bgd.count
)

ggplot(data, aes(x = x, y = y)) +
  geom_segment(aes(x = x, xend = x, y = 0, yend = y), color = "skyblue") +
  geom_point(color = "blue", size = 4, alpha = 0.6) +
  # 添加自动避让的标签，hjust=1让标签在点左侧
  geom_text_repel(aes(label = x), hjust = 1, size = 3) +
  theme_light() +
  coord_flip() +
  theme(
    panel.grid.major.y = element_blank(),
    panel.border = element_blank(),
    axis.ticks.y = element_blank(),
    # 隐藏原轴标签，避免重复显示
    axis.text.y = element_blank()
  )

2. 按数值排序后绘图 #

将数据按数值排序，让相近数值的条目集中排列，减少标签拥挤：

library(ggplot2)

df <- read.table(file = '24 hpi MP BP.tsv', sep = '\t', header = TRUE)
data <- data.frame(
  x = df$Name,
  y = df$Bgd.count
)

# 按y值排序x轴因子
data$x <- reorder(data$x, data$y)

ggplot(data, aes(x = x, y = y)) +
  geom_segment(aes(x = x, xend = x, y = 0, yend = y), color = "skyblue") +
  geom_point(color = "blue", size = 4, alpha = 0.6) +
  theme_light() +
  coord_flip() +
  theme(
    panel.grid.major.y = element_blank(),
    panel.border = element_blank(),
    axis.ticks.y = element_blank(),
    # 可选：减小标签字体进一步优化
    axis.text.y = element_text(size = 8)
  )

3. 调整图表尺寸和标签间距 #

不想额外装包的话，可以直接扩大图表边距、减小标签字体：

library(ggplot2)

df <- read.table(file = '24 hpi MP BP.tsv', sep = '\t', header = TRUE)
data <- data.frame(
  x = df$Name,
  y = df$Bgd.count
)

ggplot(data, aes(x = x, y = y)) +
  geom_segment(aes(x = x, xend = x, y = 0, yend = y), color = "skyblue") +
  geom_point(color = "blue", size = 4, alpha = 0.6) +
  theme_light() +
  coord_flip() +
  theme(
    panel.grid.major.y = element_blank(),
    panel.border = element_blank(),
    axis.ticks.y = element_blank(),
    # 减小标签字体
    axis.text.y = element_text(size = 7, hjust = 1),
    # 增加左侧边距，给标签预留更多空间
    plot.margin = margin(10, 10, 10, 50, "pt")
  )

内容的提问来源于stack exchange，提问作者RogueBio