Value that may or may not be there in field extraction

[aohls]

I am attempting to setup an exctraction for the following; 2 hrs 2 mins 36 secs 312 ms; extracting it as the time values as follows:

(?<hours>\d+) hrs (?<minutes>\d+) mins (?<seconds>\d+) secs (?<milliseconds>\d+) ms

The issue is that at times we will have something line; 1 hr 2 mins 36 secs 312 ms or even just 312 ms. Can I make the extraction account for values that may or may not be there? I know with some regex's before I used a ? to say the value may or may not be there but I am not sure in the field extractor for the full value.

[FrankVl · Accepted solution]

Something like this: EXTRACT-time = (?<hrs>\d+ hrs?)?\s*(?<mins>\d+ mins?)?\s*(?<secs>\d+ secs?)?\s*(?<ms>\d+ ms)?
https://regex101.com/r/qHE6lA/1

Or if you want to extract the whole things as 1 field: EXTRACT-time = (?<time>(?:\d+ hrs?)?\s*(?:\d+ mins?)?\s*(?:\d+ secs?)?\s*(?:\d+ ms)?)
https://regex101.com/r/qHE6lA/2

[aohls]

The top gets close, but I do not want the hrs,mins,etc included in the extracted field. for example it is extracting "2 hrs" but I was looking to get "2".

[FrankVl]

Oh, yes, ofcourse: (?<hrs>\d+)?(?: hrs?\s+)?(?<mins>\d+)?(?: mins?\s+)?(?<secs>\d+)?(?: secs?\s+)?(?<ms>\d+)?(?: ms)?
https://regex101.com/r/qHE6lA/3

[aohls]

This worked perfect. Using (?: mins?\s+)? I assume is potentially to find the word after, so it may or may not find it due to the ? at the end correct? Just want to make sure to understand it.

[FrankVl]

Yes, ? means match 0 or 1 times. So I add that behind each of the groups as well as behind the s in case it shows 1 hr or something like that.