topic Re: Regular Expression to find more than one occurence in SAS Programming

Regular Expression to find more than one occurence

Ddolic — Tue, 09 Jun 2015 14:27:54 GMT

Dear all.

I have a String variable in a Dataset with manually entered text. I try to split the text into chunks, while the delimiter consists of more than one character and the can be one or more expressions of this kind. Example:

"0 - Nothing entered or found. 1 - One or more expression- or else - entered. 99 - Missing"

Should become

Field1 Field2

0 Nothing entered or found.

1 One or more expression- or else - entered

99 Missing

I am looking for the 0 - Part using regular expressions (\d+ ?)-

Now I'm search for a possibility to not only find the first occurence of the expressions. Any help is appreciated.

Best Regards

Re: Regular Expression to find more than one occurence

RW9 — Tue, 09 Jun 2015 14:35:41 GMT

Hi,

You could use scan:

data have;

a="0 - Nothing entered or found. 1 - One or more expression- or else - entered. 99 - Missing";

run;

data want;

set have;

i=1;

do while (scan(a,i,".") ne "");

word=scan(a,i,".");

output;

i=i+1;

end;

run;

Re: Regular Expression to find more than one occurence

Ddolic — Tue, 09 Jun 2015 14:39:42 GMT

Hi RW9.

Sorry, but no. The dot at the end of each sentence is not guaranteed. That's why I think about PRX. I have to look for the expression ([0-9] - ) as delimiter.

Thanks

Re: Regular Expression to find more than one occurence

Ddolic — Tue, 09 Jun 2015 14:45:41 GMT

I found one way:

Using PRXCHANGE('s/(d+ ?)-/$1=/', -1, mytextstring); I change the expression (0 - ) into (0 =). Now I can use SCAN Function.

Re: Regular Expression to find more than one occurence

FriedEgg — Tue, 09 Jun 2015 15:11:08 GMT

Assuming you do not have numbers embedded in the strings (like in your example) you can use the following:

(\d+) - ([^\d]+)

Match 1:	0 - Nothing entered or found.	0	30
Group 1:	0	0	1
Group 2:	Nothing entered or found.	4	26
Match 2:	1 - One or more expression- or else - entered.	30	47
Group 1:	1	30	1
Group 2:	One or more expression- or else - entered.	34	43
Match 3:	99 - Missing	77	12
Group 1:	99	77	2
Group 2:	Missing	82	7

Re: Regular Expression to find more than one occurence

Ksharp — Wed, 10 Jun 2015 14:19:06 GMT

You also could use SCAN(). But I would like to use Perl Regular Expression. Check CALL PRXNEXT().

Code: Program

data have;
  a="0 - Nothing entered or found. 1 - One or more expression- or else - entered. 99 - Missing";
run;
data want;
 set have;
 length var $ 100;
 do i=1 to countw(a,,'d');
  var=catx(' ',scan(a,i,,'kd'),scan(a,i,,'d'));output;
 end;
run;

Xia Keshan