在R的ggplot2中修改图例、点样式及坐标轴标签样式

核心调整要点 #

1. 在ggplot内直接重命名type：通过factor(type, labels = c("TLA1", "TLA2", "TLA3", "TLA4"))在映射环节完成重命名，无需修改原始数据框，保证代码可复用性。
2. 点形状与类型绑定：将shape映射到重命名后的type，同时搭配颜色映射，让不同类型的散点区分更清晰。
3. x轴刻度标签着色：先匹配每个Tag对应的type颜色，再通过主题设置给刻度标签上色。

完整可复用代码 #

# 先处理Percentage的格式（替换逗号为点，转换为数值型）
MeMeT1A$Percentage <- as.numeric(gsub(",", ".", MeMeT1A$Percentage))

ggplot(MeMeT1A, aes(x = Tag, y = Percentage, 
                    shape = factor(type, labels = c("TLA1", "TLA2", "TLA3", "TLA4")),
                    color = factor(type, labels = c("TLA1", "TLA2", "TLA3", "TLA4")))) +
  geom_point(size = 3) +
  labs(title = "Top5 Medulla Input Types", 
       x = "Inputneuron", 
       y = "(%) medulla input",
       shape = "Experimental Condition",
       color = "Experimental Condition") +
  # 手动设置点形状和颜色
  scale_shape_manual(values = c(15, 16, 17, 18)) +
  scale_color_manual(values = c("#999999", "#E69F00", "#56B4E9", "#E69F00")) +
  theme_bw() +
  geom_hline(yintercept = seq(0, 1, by = 0.1), linetype = "longdash", color = "gray") +
  # 设置x轴样式，包括刻度颜色
  theme(
    text = element_text(size = 8), 
    axis.text.x = element_text(angle = 45, hjust = 1,
                               color = c("#999999", "#999999", "#E69F00", "#E69F00", "#56B4E9", "#56B4E9", "#E69F00"))
  )

补充说明 #

如果Tag的顺序不固定，不想手动写颜色向量，可以用以下代码动态生成对应颜色：

library(dplyr)
# 动态获取每个Tag对应的颜色
tag_color <- MeMeT1A %>% 
  distinct(Tag, type) %>% 
  mutate(color = case_when(
    type == 1 ~ "#999999",
    type == 2 ~ "#E69F00",
    type == 3 ~ "#56B4E9",
    type == 4 ~ "#E69F00"
  )) %>% 
  pull(color)

之后在theme的axis.text.x里把color参数换成tag_color即可。

内容的提问来源于stack exchange，提问作者Miga