I have a character vector containing variable names such as
x <- c("AB.38.2", "GF.40.4", "ABC.34.2"). I want to extract the letters so that I have a character vector now containing only the letters e.g.
c("AB", "GF", "ABC").
Because the number of letters varies, I cannot use
substring to specify the first and last characters.
How can I go about this?