regex - R Splitting one column into two, when delimiter is '..' -

i have data frame looks this:

     x1                     x3 1: thrl               190..255 2: thra              337..2799 3: thrb             2801..3733 4: thrc             3734..5020 5: yaax             5234..5530 6: yaaa complement(5683..6459) 7: yaaj complement(6529..7959) 

i struggling separate dataframe 3 columns using .. separator. i've tried other solutions on similar posts such splitstackshape , gsub, none have worked because when delimiters not wildcard values periods.

     x1   x2   x3  x4 1: thrl  190  255   f 2: thra  337 2799   f 3: thrb 2801 3733   f 4: thrc 3734 5020   f 5: yaax 5234 5530   f 6: yaaa 5683 6459   r 7: yaaj 6529 7959   r 

this i'm trying right now

concat.split.multiple(i, "x3", "\\.\\.") 

any suggestions?

thanks in advance

using dplyr , tidyr:

library(dplyr) library(tidyr) df %>%    mutate(x4=ifelse(grepl("complement", x3), "f", "r")) %>%     mutate(x3=gsub("[a-z()]", "", x3)) %>%    separate(x3, into=c("x2", "x3"), sep="\\.\\.")