regex - Add space between two letters in a string in R -

regex - Add space between two letters in a string in R -

suppose have string like

s = "pleaseaddspacesbetweenthesewords"

how utilize gsub in r add together space between words get

"please add together spaces between these words"

i should like

gsub("[a-z][a-z]", ???, s)

what set ???. also, find regular look documentation r confusing reference or writeup on regular expressions in r much appreciated.

you need capture matches utilize \1 syntax refer captured matches. example

s = "pleaseaddspacesbetweenthesewords" gsub("([a-z])([a-z])", "\\1 \\2", s) # [1] "please add together spaces between these words"

of course, puts space between each lower-case/upper-case letter pairings. doesn't know real "word" is.

regex r gsub