Question

我有这样的df：

df<- data.frame(result=c("p","p","p","d","d","p"),lep=c("A", "C", "E", "F","G", ""), psit= c("B", "D", "F", "G","H", ""))

如果符合以下要求，我想制作一个新的专栏paste，将两个级别的不同因素粘贴在一起：1）result必须= p 2）lep和psit列不是空白

输出应如下所示：

output<- data.frame(result=c("p","p","p","d","d", "p"),lep=c("A","C", 
"E", "F","G", ""), psit= c("B", "D", "F", "G","H",""), paste= 
c("A_B","C_D", "E_F", "", "",""))

我试过以下但没有成功。我相信这是因为我没有正确使用粘贴功能：

df<-df %>%
 group_by(result) %>% 
  mutate(interact2=ifelse(psit==""| lep==""|result!="p", psit, 
                   paste0(lep, psit, sep= "_")))

Answer 1

正如@thelatemail所说，情况似乎有些混乱。此外，我认为您不需要group_by。

library(dplyr)
df %>%
   mutate(paste = ifelse(result == "p" & (lep != "" & psit != ""), 
                  paste(lep, psit, sep = "_"), ""))

#  result lep  psit paste
#1      p   A    B   A_B
#2      p   C    D   C_D
#3      p   E    F   E_F
#4      d   F    G      
#5      d   G    H      
#6      p

Answer 2

以下是data.table分配到位的选项

library(data.table)
setDT(df)[result == "p" & lep !="" & psit != "", paste := paste(lep, psit, sep="_")][]

给出条件语句的两个级别的不同因素

2 个答案: