Replace value of an existing column based on whether it's present in a list

Question

I have a sample data frame as such:

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"))

I would like to create a new column based on the value of column V2. If column V2 is %in% ("Income","Cost") then I would like the new column to pick column V3, if not in the list then V2.

I was thinking about using the %in% function but not sure how I would go about doing an if in this list then get this column else get this column logic.

Help is most appreciated. Regards,

Answer 1

Is this what you're looking for?

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

Alternatively, using %in% as you mentioned:

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

Data:

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)