topic Re: Issue with macro variables %let in SAS Programming

Issue with macro variables %let

Jcorti — Fri, 05 May 2017 13:19:21 GMT

Hi Team,

I am getting an issue when I am delcaring macro variables,

data test;
%let %do i=0 %to 24;

%let var1=a&i;
%let var2=b&i;
%let var3=c&i;
%let var4=d&i;
%let var5=e&i;
%let month=period&i;
output;
%end;
run;

This is the error;

ERROR: Open code statement recursion detected.

Anyone can Help me on this??

Thanks a lot in advance

Re: Issue with macro variables %let

Astounding — Fri, 05 May 2017 13:23:02 GMT

You are trying to use macro language without knowing basic concepts:

What should a %LET statement look like
When is a %DO statement permissible
What is the relationship between macro language and SAS language

If you describe what you are trying to accomplish, you can get answers to a specific question. But the studying part is up to you.

Re: Issue with macro variables %let

robert215 — Fri, 05 May 2017 13:24:41 GMT

Hi ,

What should the output dataset test look like ?

Re: Issue with macro variables %let

novinosrin — Fri, 05 May 2017 13:28:07 GMT

Well, You simply cannot declare two macro statements in one i.e %let and %do, these are 2 independent exclusive statements. So that's an absolute NO there.

Open code recursion was simply caused by not finding the end of macro statement ; and if often contributed to be known as black hole problem

What is that you want to accomplish?

Re: Issue with macro variables %let

Kurt_Bremser — Fri, 05 May 2017 13:28:44 GMT

%do is only allowed within a macro definition, and no %let should be done within another %let; Since your %do is within a %let, all other macro statements are considered part of that first %let.

Bottom line: start with simple code before turning to complex things. And DO NOT get into macros before you have a thorough grasp of programming as such. The macro language needs a programmer's mindset.

Re: Issue with macro variables %let

RW9 — Fri, 05 May 2017 13:33:58 GMT

The problem is with the %end. Macro language should always be encased within %macro and %mend statements such as:

%macro tmp();
  %if a=b %then %do;
    ..
  %end;
%mend tmp;

Secondly, why do you have a load of %let statements in a datastep? Macro is nothing to do with Base SAS - which is the lanaguage. Put your %let statements at the top of the code, they are only there for find/replace.

Your second problem is this statments:

%let %do i=0 %to 24;

Macro do loops are not define with %let.

Re: Issue with macro variables %let

Jcorti — Fri, 05 May 2017 14:28:52 GMT

Thanks Team,

I did some adjustment to my code based on all your suggestions:

%macro vars; 
%let outobs=max;
%do i=0  %to 24;
%let b =&i;
%let var1=test1&b;
%let var2=test2t&b;
%let var3=test3&b;
%let var4=test4t&b;
%let var5=test5&b;
%let var6=test6&b;
%let month=period_&b;

proc  sql;
create table &month as	   
select
filler5
,&var1
,&var2
,&var3
,&var4
,&var5
,&var6
,case when &var1<>-16 or &var2<>-16
or &var3<>-16 or &var4<>-16 or &var5 is not null then 1 else 0 end as
&month

from SAS_Out.&Data_Out
WHERE a='x';
;
run;
%end;
run;

%mend vars;
%vars;

And it worked perfectly.

An now can you understand what I am tryng to do??

Thanks Again all

Re: Issue with macro variables %let

RW9 — Fri, 05 May 2017 14:35:23 GMT

Quite frankly no. You appear to be creating 24 datasets, for no reason. You have a call to a macro variable &data_out never defined, and you refer to a variable A in your proc sql which is not selected, and the same across all datasets.

This can all be done in one dataset, and have a variable called period which goes from 1-24, this will make your programming far easier in the long run:

data want;
  do period=1 to 24;
    set sas_out.&data_out.;
    if ...;
    output;
  end;
run;

However it is impossible to say without seeing some test data (form of a datastep) and what the output should look like - other than one dataset would be better than many.