Date:         Wed, 20 Dec 2006 09:23:20 -0500
Reply-To:     Gerhard Hellriegel <gerhard.hellriegel@T-ONLINE.DE>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Gerhard Hellriegel <gerhard.hellriegel@T-ONLINE.DE>
Subject:      Re: Optional parameters in a macro

To give it a frame:

%macro ilist(start,end,step);
  %if &step=  %then %let step=1;
  %if &end=  %then %do;
    %let end=&start;
 %let start=1;
  %end;
  %do i=&start %to &end %by &step;
     &i
  %end;
%mend;

%put Results in %ilist(5);

Regards,
Gerhard




On Wed, 20 Dec 2006 05:53:44 -0800, abose <hirak99@GMAIL.COM> wrote:

>Thanks all
>@Gerhard Hellriegel: That was really cool, exactly what I was looking
>for!
>
>What I actually need is a macro ILIST which will take max three
>variables, and return a list like:
>ILIST(5) --> 1 2 3 4 5
>ILIST(3,5) --> 3 4 5
>ILIST(1,5,2) --> 1 3 5 (third variable is step)
>
>Now I feel I can do it :)
>Thanks a lot for helping!
>
>On Dec 20, 5:52 pm, gerhard.hellrie...@T-ONLINE.DE (Gerhard Hellriegel)
>wrote:
>> Perhaps like that:
>>
>> %macro sum(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13);
>>   %let sum=0;
>>   %do i=1 %to 13;
>>     %if &&a&i= %then %let a&i=0;
>>     %let sum=%eval(&sum+&&a&i);
>>   %end;
>>   &sum;
>> %mend;
>>
>> %put %sum(1,2,3);
>>
>> On Wed, 20 Dec 2006 04:21:37 -0800, RolandRB <rolandbe...@HOTMAIL.COM> wrote:
>> >abose wrote:
>> >> Hi,
>> >> Is there any way I can write a macro which will take optional
>> >> parameters? For example, can I create something like a sum macro which
>> >> works on 2 OR 3 variables:
>>
>> >> %sum(3,4) returns 7
>> >> %sum(3,4,5) returns 12?
>>
>> >Yes, use enough positional parameters to cover any usage of the macro.