BookmarkSubscribeRSS Feed
🔒 This topic is solved and locked. Need further help from the community? Please sign in and ask a new question.
allaboutsas
Calcite | Level 5

Is there a way to use lookbehind for a few possible letters as a whole? In the example below, I need ABC, DEF, GHI be found as a whole (ABCDE is ok), but seems like it was taken as each letter. I tried (ABC|DEF|GHI), it’s not working, one word is working. Any suggestions?

data a;

     var='ABC 1.89 DEF A YELLOW LINES'; output;

     var='ABC 1.89 YELLOW JKLM LINE'; output;

     var='9 GHI YELLOW LINE'; output;

     var='9 H BLK LINE'; output;

     var='9 BC JT GREEN LINE'; output;

run;

data b;

     set a;

     retain re1;

     if _N_=1 then do;

           re1 = prxparse('/(?<=[ABC|DEF|GHI] )(YELLOW|BLK|GREEN)(?=\s*LI)/');

     end;

     if prxmatch(re1,var) then do;

           var2 = prxposn(re1,0,var);

     end;

run;

proc print data=b; run;

1

ABC 1.89 DEF A YELLOW LINES

1

YELLOW

2

ABC 1.89 YELLOW JKLM LINE

1

3

9 GHI YELLOW LINE

1

YELLOW

4

9 H BLK LINE

1

BLK

5

9 BC JT GREEN LINE

1

1 ACCEPTED SOLUTION

Accepted Solutions
gergely_batho
SAS Employee

I think you need () instead of []

prxparse('/(?<=(ABC|DEF|GHI) )(YELLOW|BLK|GREEN)(?=\s*LI)/')

View solution in original post

5 REPLIES 5
ballardw
Super User

Please provide details on what you mean by "not working"? What was your expected output?

allaboutsas
Calcite | Level 5

For example if I have “re1 = prxparse('/(?<=ABC).*(\bYELLOW|BLK|GREEN\b)(?=\s*LI)/');” in code, so ‘YELLOW’ in “ABC 1.89 DEF A YELLOW LINESwill be captured, but I need to list more possible words, like GHI, so YELLOW in 9 GHI YELLOW LINE”’ can be captured too.

gergely_batho
SAS Employee

I think you need () instead of []

prxparse('/(?<=(ABC|DEF|GHI) )(YELLOW|BLK|GREEN)(?=\s*LI)/')

allaboutsas
Calcite | Level 5

gergely! you are right. I thought I tried that, got error earlier, I must have added an extra closed parenthesis. Thank you!

allaboutsas
Calcite | Level 5

Hi, is there a way to look around, either ahead or behind, for example, as long as ABC or GHI is in the string, before or after (\bYELLOW|BLK|GREEN\b) return the color?

hackathon24-white-horiz.png

2025 SAS Hackathon: There is still time!

Good news: We've extended SAS Hackathon registration until Sept. 12, so you still have time to be part of our biggest event yet – our five-year anniversary!

Register Now

What is Bayesian Analysis?

Learn the difference between classical and Bayesian statistical approaches and see a few PROC examples to perform Bayesian analysis in this video.

Find more tutorials on the SAS Users YouTube channel.

SAS Training: Just a Click Away

 Ready to level-up your skills? Choose your own adventure.

Browse our catalog!

Discussion stats
  • 5 replies
  • 1514 views
  • 0 likes
  • 3 in conversation