In R,
I have a vector of 5 unique elements:
X<-c("A","B","C","D","E")
And a vector of repeated elements:
Y<- c("A","C","M","Z","B","C","C","R","V","D","D","B","A","V","E","E")
I want to obtain the position of elements of Y that a are in X becase Y are rownames of a matrix.
But Y[match(Y,X)] gives:
[1] "A" "M" NA NA "C" "M" "M" NA NA "Z" "Z" "C" "A" NA "B" "B"
The response should be:
c("A","C",NA,NA,"B","C","C",NA,NA,"D","D","B","A",NA,"E","E").
to select the rows:
Y[-which(is.na(Y[match(Y,X)]))]
Is there a better and more elegant alternative?