Reverse/flip the sides of two strings based on a delimiter?-CodePudding

say I have the following strings.

st = c( "50/90", "cat/dog,sheep", "08/25,000")

is there a function I can use to flip the order based on the "/" delimiter?

c("90/50", "dog,sheep/cat", "25,000/08" )

CodePudding user response：

We could capture as a group ((...)) and reverse the backreference (\\1, \\2) order

sub("^([^/] )/(.*)", "\\2/\\1", st)
[1] "90/50"         "dog,sheep/cat" "25,000/08"

CodePudding user response：

We can write one pretty easily:

st = c( "50/90", "cat/dog,sheep", "08/25,000")
strsplit(st, "/", fixed = TRUE) |>
  lapply(rev) |>
  sapply(paste, collapse = "/")
# [1] "90/50"         "dog,sheep/cat" "25,000/08"

CodePudding user response：

with(read.table(text=st, sep='/'), paste(V2, V1, sep='/'))

[1] "90/50"         "dog,sheep/cat" "25,000/08"

or even

do.call(paste, c(sep='/', rev(read.table(text=st, sep='/'))))

[1] "90/50"         "dog,sheep/cat" "25,000/08"