topic Re: loops in macro in SAS Programming

Do Loop

Eco — Sat, 17 Aug 2019 16:12:59 GMT

Hi everyone, I have a question about loop. Here I have a sample data set:

data sample;
input stkcd $ ViolationYear $30.;
datalines;
000003 2001
000004 2008,2009,2010
000007 2011,2012,2013,2014
;
run;

I want to split the year in ViolationYear and rearrange to be like one stkcd match one ViolationYear liike:

000003 2001

000004 2008

000004 2009

000004 2010

000007 2011

000007 2012

and so on.

I am wondering if I can use a loop to achieve this or is there any other better choice? Looking forward to your suggestions.

Best

Re: loops in macro

Tom — Sat, 17 Aug 2019 16:16:06 GMT

There is no need for MACRO code for this problem. You don't need to generate code statements. Just write normal SAS code to generate the observations you want.

data sample;
  input stkcd :$10. ViolationYear :$30.;
datalines;
000003 2001
000004 2008,2009,2010
000007 2011,2012,2013,2014
;

data want ;
  set sample;
  do sample_no=1 by 1 until (sample_no=countw(ViolationYear,','));
     Year = input(scan(ViolationYear,sample_no,','),32.);
     output;
  end;
  drop ViolationYear;
run;

proc print;
run;

Result:

                 sample_
Obs    stkcd        no      Year

 1     000003       1       2001
 2     000004       1       2008
 3     000004       2       2009
 4     000004       3       2010
 5     000007       1       2011
 6     000007       2       2012
 7     000007       3       2013
 8     000007       4       2014

Re: Do Loop

Kurt_Bremser — Sat, 17 Aug 2019 16:16:26 GMT

Nothing to do with macro (that's why I changed the subject line).

But it's done with a data step do loop and some string functions:

data want;
set sample;
do i = 1 to countw(violationyear,',');
  year = input(scan(violationyear,i,',');
  output;
end;
drop i violationyear;
run;

@Eco wrote:

Hi everyone, I have a question about loop. Here I have a sample data set:
data sample;
input stkcd $ ViolationYear $30.;
datalines;
000003 2001
000004 2008,2009,2010
000007 2011,2012,2013,2014
;
run;
I want to split the year in ViolationYear and rearrange to be like one stkcd match one ViolationYear liike:

000003 2001

000004 2008

000004 2009

000004 2010

000007 2011

000007 2012

and so on.

I am wondering if I can use a loop to achieve this or is there any other better choice? Looking forward to your suggestions.

Best

Re: loops in macro

Eco — Sat, 17 Aug 2019 16:36:57 GMT

Thank you very much Tom, it seems I have made the queation complicate.

Re: Do Loop

Eco — Sat, 17 Aug 2019 16:39:38 GMT

Thank you Kurt, it works~ It seems I have made the question complicate.

Re: loops in macro

Eco — Sat, 17 Aug 2019 16:47:16 GMT

By the way, is there any way that I can find such kind of functions or to learn them systematiclly? I think these functions are so tiny that I cannot find them easily...

Re: loops in macro

PaigeMiller — Sat, 17 Aug 2019 17:09:26 GMT

@Eco wrote:

By the way, is there any way that I can find such kind of functions or to learn them systematiclly? I think these functions are so tiny that I cannot find them easily...

This is a very vague question, and yes, there are a gajillion books and tutorials available on SAS that will help you learn, plus comprehensive online documentation.

One helpful book is called "The Little SAS Book". Some others are listed here: https://documentation.sas.com/?cdcId=pgmsascdc&cdcVersion=9.4_3.3&docsetId=lefunctionsref&docsetTarget=p0w77a6p4lu418n15il3ltm2y1vv.htm&locale=en

Re: loops in macro

Eco — Sat, 17 Aug 2019 17:14:52 GMT

Oh yes, The Little SAS Book. I heard about it before but I haven't tried it. The reference books that I used from now are my university's teaching materials which are not enough for now. It seems to be a long journey for me to learn SAS. Thank you for your suggestion~

Re: loops in macro

Kurt_Bremser — Sat, 17 Aug 2019 18:41:47 GMT

Maxim 1: Read the Documentation. For functions, go here: https://documentation.sas.com/?cdcId=pgmsascdc&cdcVersion=9.4_3.4&docsetId=lefunctionsref&docsetTarget=titlepage.htm&locale=en