Question

我有一个示例数据框：

dat <- data.frame(V1 = c("Non Debt Balance","Non Debt Income","Non Debt Cost"), 
              V2 = c("Average Balance","Income","Cost"), 
              V3 = c("Trade","Sales Finance","Trade"))

我想根据V2列的值创建一个新列。如果列V2是％in％（＆＃34; Income＆＃34;，＆＃34; Cost＆＃34;）那么我希望新列选择列V3，如果不在列表中则选择V2。

我在考虑使用％in％函数，但不确定如何在此列表中执行if，然后获取此列以获取此列逻辑。

非常感谢帮助。的问候，

Answer 1

这是你正在寻找的吗？

library(dplyr)

dat %>% 
  mutate(V4 = case_when(V2 == "Income" | V2 == "Cost" ~ V3,
                        TRUE ~ V2))

                V1              V2            V3              V4
1 Non Debt Balance Average Balance         Trade Average Balance
2  Non Debt Income          Income Sales Finance   Sales Finance
3    Non Debt Cost            Cost         Trade           Trade

或者，如您所述使用%in%：

dat %>% 
  mutate(V4 = case_when(V2 %in% c("Cost", "Income") ~ V3,
                        TRUE ~ V2))

数据：

dat <- data.frame(V1 = c("Non Debt Balance","Non Debt Income","Non Debt Cost"), 
                  V2 = c("Average Balance","Income","Cost"), 
                  V3 = c("Trade","Sales Finance","Trade"),
                  stringsAsFactors = FALSE)

Answer 2

dat$NewCol <- ifelse(dat$V2 %in% c('Income','Cost'), dat$V3, dat$V2)

您也可以使用dplyr / data.table
ifelse没有最佳表现。此外，您无法进行NA感知比较（即使用NA子句进行三向选择）

Answer 3

data.table方式：

 result <- setDT(dat)[,result_col:= ifelse(V2 %in% c('Income','Cost'), V3, V2)]


> result

    V1                    V2            V3             result_col
1  Non Debt Balance   Average Balance  Trade         Average Balance
2  Non Debt Income       Income     Sales Finance     Sales Finance
3  Non Debt Cost          Cost         Trade             Trade

根据列中是否存在现有列的值来替换它

3 个答案: