R: ifelse function returns vector position instead of value (string)

Question

I have a very strange problem concerning the ifelse function: it does not return a factor (as I want) but something like the position of the factor.

The dataset I u

Answer 1

Modify your ifelse as follows

aDDs$top <- ifelse(
        aDDs$answer %in% temp, ## condition: match aDDs$answer with row.names in summary df 
        levels(aDDs$answer)[aDDs$answer], ## then it should be named as aDDs$answer **THIS IS THE PROBLEM**
        "Other" ## else it should be named "Other"
      )

Notice the function levels and the box brackets. Levels knows how many factors are their and their index. So, essentially what we are saying is give me the the factor value corresponding to some index value.

Sample demo:

topCountries<-as.factor(c("India", "USA", "UK"))
AllCountries<-as.factor(c("India", "USA", "UK", "China", "Brazil"))
myData<-data.frame(AllCountries)
myData

myData$top<-ifelse(
        myData$AllCountries %in% topCountries,
        levels(myData$AllCountries)[myData$AllCountries], 
        "Other" 
      )


myData

the top column in myData will have "Other" for China & Brazil. For rows where Allcountries in {India, USA, UK} it will return their respective values i.e., {India, USA, UK} . Without the use of levels it will return "Other" and factor index values for {India, USA, UK} .