在R中提取唯一基因并按A/B分组标注归属类别

我有如下R语言数据框deg：

summary(deg)
      L2FC            Gene                    diffexp    comp   
 Min.   :-3.825   Length:926         Downregulated:210   A:195  
 1st Qu.: 1.010   Class :character   Upregulated  :716   B:731  
 Median : 1.163   Mode  :character                              
 Mean   : 0.860                                                 
 3rd Qu.: 1.431                                                 
 Max.   : 6.505    

head(deg)
       L2FC    Gene       diffexp comp
1 -2.754236 SLC13A2 Downregulated    A
2  3.161623   SNAI2   Upregulated    A
3 -2.821350   STYK1 Downregulated    A
4 -1.798022    CD84 Downregulated    A
5 -1.293536    TLE6 Downregulated    A
6 -1.011016   P2RX1 Downregulated    A

需要提取唯一的Gene符号，并按以下规则标注所属分组：

• 1：仅属于分组A
• -1：仅属于分组B
• 0：同时属于A和B两组

期望输出格式如下：

Gene comp
1 GENE1    1
2 GENE2    0
3 GENE3   -1

方法一：用dplyr包实现 #

library(dplyr)

result <- deg %>%
  group_by(Gene) %>%
  summarise(
    comp = case_when(
      all(comp == "A") ~ 1,
      all(comp == "B") ~ -1,
      TRUE ~ 0
    ),
    .groups = "drop"
  )

# 查看结果
head(result)

方法二：基础R实现（无需额外包） #

# 按Gene分组，获取每个基因对应的唯一分组
gene_comps <- tapply(deg$comp, deg$Gene, unique)

# 根据分组情况生成标注值
comp_labels <- sapply(gene_comps, function(x) {
  if (length(x) == 1) {
    if (x == "A") 1 else -1
  } else {
    0
  }
})

# 转换为目标数据框
result <- data.frame(
  Gene = names(comp_labels),
  comp = as.integer(comp_labels),
  row.names = NULL
)

# 查看结果
head(result)

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