如何使用R语言ggplot2绘制示例样式的表格型热图

原代码存在两处核心错误导致效果不符合预期：

• 映射x轴时给Countries加了单引号，被识别为固定字符串而非数据框列，导致x轴仅显示1个分类
• 缺少单元格样式和坐标适配配置，和表格样式的热图效果不匹配

完整可运行修改后代码 #

TestData1<-structure(list(Countries = c("AL", "CA", "DE", "ES", "MA", "EL", 
                                        "AL", "CA", "DE", "ES", "MA", "EL", "AL", "CA", "DE", "ES", "MA", 
                                        "EL"), variable = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 
                                                                      2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L), .Label = c("Total", 
                                                                                                                          "Female", "Male"), class = "factor"), value = c(-3.06, -4.41, 
                                                                                                                                                                          6.97, -2.74, 5.54, -1.31, -2.47, -3.45, 4.11, -3.06, 4.82, -1.73, 
                                                                                                                                                                          -3.95, -5.76, 8.74, -1.87, 6.37, -0.79)), row.names = c(NA, -18L
                                                                                                                                                                          ), class = "data.frame")

library(ggplot2)
ggplot(TestData1, aes(x = Countries, y = factor(variable, levels = rev(levels(factor(variable)))))) + 
  geom_tile(aes(fill = value), color = "white") + 
  geom_text(aes(label = value), color = "white") + 
  scale_x_discrete(position = "top") +
  scale_fill_gradient(high = "#132B43", low = "#56B1F7") +
  coord_equal() +
  theme(legend.position = "none", 
        panel.grid = element_blank(), 
        panel.background = element_rect(fill = "white"),
        axis.ticks = element_blank(),
        axis.title.x = element_blank()) +
  labs(y = " ")

关键修改说明 #

• 移除x参数的单引号，正确映射国家列，生成6个国家对应的x轴分类
• geom_tile新增color = "white"参数，添加单元格白色边框，和示例的表格分隔效果一致
• 新增coord_equal()配置，强制x、y轴等比例，让每个单元格为正方形，符合表格热图的视觉效果
• 移除x轴标题，和示例样式匹配

内容的提问来源于stack exchange，提问作者silent_hunter