regular expression capture nth match

Question

Is there any way to, using regular expression, return the nth occurrence? I did search the forums and only found solution that goes beyond regular expression itself (i.e. needs support from the programming language).

Example: Regex:

(?:\$(\d+(?:,\d{3})*\.\d{2}))

Input:

    thiscanbeanything$25.74thiscanbesomethingelse
alsowithnewlines$533.63thisonetoo$54.32plusthis$62.42thisneverends

I'd need to extract the first one (which is 25.74). Later on I might need to extract the third one (which is 54.32).

My regex is currently matching all occurrences. I could retrieve the nth element after matches but my question is: is it possible to do it via regular expression only (i.e. the regular expression will return only the nth element I want)?

Thanks!

Answer 1

for nth match use this pattern (?:.*?\$[0-9.]+){XX}.*?(\$[0-9.]+)
where XX = n-1

Example for 3rd match