topic Re: how to use "do loop" with skips? in SAS Procedures

how to use "do loop" with skips?

Ken_oy — Thu, 08 May 2014 15:31:54 GMT

I want to do:

%DO i = 1 %to 100; but I want to skip some numbers, e.g. let said 9, and 50;

My code is:

%DO i = 1 %TO 8;

%FUNC;

%END;

%DO i = 10 %TO 49;

%FUNC;

%END;

%DO i = 51 %TO 100;

%FUNC;

%END;

Is there any way to make it more efficient? Thanks!!

Re: how to use "do loop" with skips?

Quentin — Thu, 08 May 2014 15:50:44 GMT

Hi,

If you don't mind a %GOTO, you could do something like:

%macro loop(dummy);
  %local i;
  %do i=1 %to 100;
    %if &i=9 or &i=50 %then %goto skipped;

    %*Main code here;
    %put i=&i;

    %skipped:
  %end;
%mend loop;

%loop()

There is a popular ballotware suggestion for enhancements to macro looping, to give it more of the features of data step do loops:

https://communities.sas.com/ideas/1084

HTH,

--Q.

Re: how to use "do loop" with skips?

jwillis — Thu, 08 May 2014 15:51:07 GMT

%macro testit2;

%DO i = 1 %to 100;

%if ((&i. ne %eval(9)) and (&i. ne %eval(50))) %then %do;

%put "i = &i.";

%end;

%END;

%mend testit2;

%testit2;

Re: how to use "do loop" with skips?

pawan — Thu, 08 May 2014 16:14:25 GMT

Hi Ken, I think you can give a try as below...

%DO i = 1 %TO 8, 10 %TO 100;

%DO i = 1 %TO 8, 10 %TO 49, 50 %TO 100;

Above code worked for me. All the Best!!

Re: how to use "do loop" with skips?

Quentin — Thu, 08 May 2014 18:07:58 GMT

pawan wrote:

Hi Ken, I think you can give a try as below...

%DO i = 1 %TO 8, 10 %TO 100;

%DO i = 1 %TO 8, 10 %TO 49, 50 %TO 100;

Above code worked for me. All the Best!!

Unfortunately, that sort of list works for data step DO loops, but not macro %DO loops:

16         %macro loop(dummy);
17         %do i = 1 %TO 8, 10 %TO 20;
18         %end;
19         %mend;
NOTE: The macro LOOP completed compilation without errors.
      9 instructions 184 bytes.
20         %loop()
ERROR: A character operand was found in the %EVAL function or %IF condition where a 
       numeric operand is required. The condition was: 8, 10 %TO 20 
ERROR: The %TO value of the %DO I loop is invalid.
ERROR: The macro LOOP will stop executing.