如何在gratia包中不修改数据框变量名修改绘图标题与轴标签

方法1：在draw()函数中直接指定自定义标签映射 #

通过draw()的labeller参数，结合ggplot2::labeller定义变量和光滑项的显示标签，无需后续修改子图：

library(patchwork)
library(gratia)  
library(ggplot2)

set.seed(123)
data <- data.frame(
  y = rnorm(100),    
  x1 = rnorm(100),   
  x2 = rnorm(100)    
)

model <- gam(y ~ s(x1) + s(x2), data = data)

# 定义标签映射
var_labels <- c(
  x1 = "素食人数",
  x2 = "血液中铁含量"
)

smooth_title_labels <- c(
  "s(x1)" = "s(素食人数)",
  "s(x2)" = "s(血液中铁含量)"
)

# 绘图时指定labeller
smooth_plot <- draw(model, 
                    ci_col = "steelblue", 
                    smooth_col = "blue", 
                    grouped_by = TRUE,
                    labeller = labeller(
                      # 映射x轴变量标签
                      variable = ~ var_labels[.x],
                      # 映射光滑项标题
                      smooth = ~ smooth_title_labels[.x]
                    )) 

smooth_plot <- smooth_plot + plot_layout(nrow = 1, ncol = 2)

print(smooth_plot)

方法2：遍历patchwork子图手动修改标签 #

如果需要更灵活的调整，可以直接提取patchwork中的每个子图，逐个修改轴标签和标题后重新组合：

library(patchwork)
library(gratia)  
library(purrr)
library(ggplot2)

set.seed(123)
data <- data.frame(
  y = rnorm(100),    
  x1 = rnorm(100),   
  x2 = rnorm(100)    
)

model <- gam(y ~ s(x1) + s(x2), data = data)
smooth_plot <- draw(model, ci_col = "steelblue", smooth_col = "blue", grouped_by = TRUE) 

# 定义标签映射表
x_label_map <- c("x1" = "素食人数", "x2" = "血液中铁含量")
title_map <- c("s(x1)" = "s(素食人数)", "s(x2)" = "s(血液中铁含量)")

# 遍历每个子图修改标签
modified_plots <- map(smooth_plot$plots, function(sub_plot) {
  # 获取当前子图的x轴标签和标题
  current_x <- sub_plot$labels$x
  current_title <- sub_plot$labels$title
  
  # 替换标签并返回修改后的子图
  sub_plot +
    labs(
      x = x_label_map[current_x],
      title = title_map[current_title]
    )
})

# 重新组合为patchwork并设置布局
smooth_plot_modified <- wrap_plots(modified_plots) + plot_layout(nrow = 1, ncol = 2)

print(smooth_plot_modified)

两种方法都无需修改原始数据框的变量名：方法1简洁高效，适合批量统一替换；方法2灵活性强，适合对特定子图做额外调整。

内容的提问来源于stack exchange，提问作者F3d33