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SOLVED

pulling specific rows of data

Wynn
8 - Asteroid

Hi!

 

Could someone please help me write out the regex expression to pull the specific rows of data in the attached file below ( highlighted) Basically, I'm trying to pull the data starting with "Total ###( 3 digits) ". There are several rows of data starting with "data" but I just want to get the one following by 3 digits and then -. Thanks so much in advance !

5 REPLIES 5
TomWelgemoed
12 - Quasar

Hi @Wynn ,

 

For this case I think you can just use (\d+) in the Regex Parse method.

 

Regards,

Tom

Wynn
8 - Asteroid

Hi @TomWelgemoed ,

 

Thank you so much for your help! The solution is great. However, I just have a question for future for reference. What is really the difference between "+" vs *.

In your expression, you used (\d+) instead of (\d*). I'm aware that * means "zero or more" and + means " one or more". Do you mind providing an example to suggest when I should use * instead of + or vice versa? I found this super confusing some time.

Thanks again for your help! Really appreciate this.

Wynn
8 - Asteroid

Hi @TomWelgemoed ,

 

Just tagged you here again in case you missed my last reply. Please see my previous reply when you have a chance. Thanks!

TomWelgemoed
12 - Quasar

Hi @Wynn ,

 

Firstly, apologies for the delay. I did see your note and it was on my list to respond to!

Secondly, good on you for trying to really understand it.

 

The reason I didn't get back to you straight away is because I needed to understand it better myself. I'm no regex expert, and often have to test it to learn it myself. If you don't know this already, I can really recommend https://regexr.com/ for trying out regex - you can just cut & paste your text there and try out different methods.

 

To trial your question, I simply expanded our set of data with some other numeric examples and then compared the 2 outputs. So take this as an investigative result, rather than an expert's view:

 

To me it looks like the \d* method only really works on numbers - it doesn't appear to be very good at picking out the digits that follow text. See image below. The \d+ method however does appear to be very good at picking out the first group of digits it comes across across (that match the pattern specified). Also, when I put the \d* method on regexr.com, a warning pops up on the top right, saying that this method may have some undesired effects. So my 2 cents: probably best to avoid it as \d+ seems to cover all the required scenarios. Attaching the workflow for you.

 

Best,

Tom

 

Regex.png

Wynn
8 - Asteroid

Hi @TomWelgemoed ,

 

Thanks so much for taking your time to answer my questions. It is really helpful. I truly appreciate your effort.

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