Date:         Tue, 9 Sep 2008 11:58:03 -0500
Reply-To:     Mary <mlhoward@avalon.net>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Mary <mlhoward@AVALON.NET>
Subject:      Re: KEEP DROP array variables
Comments: To: "jlee8071@gmail.com" <jlee8071@GMAIL.COM>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
              reply-type=original

This seems to work:

data test;
informat var1 var2 var3 var4 $2.;
infile cards;
input var1 var2 var3 var4;
cards;
AA BB BC DD
DD CC DC AA
;
run;

%macro macrowrapper;

%let keeplist= ;

proc sql noprint;
    select max(varnum) into: varnum
    separated by " "
    from dictionary.columns
    where libname eq "WORK"
    and memname eq "TEST";
quit;

%put &varnum;

%do i=1 %to &varnum;
    proc sql noprint;
        select NAME into: VarList1
        separated by " "
        from dictionary.columns
        where libname eq "WORK"
        and memname eq "TEST"
        and varnum= &i;
    quit;
    %put &varlist1;

    proc sql;
        select count(&varlist1) into :countc
        from test
        where &varlist1='DD';
    quit;
    %put &countc;

    %if &countc > 0 %then %do;
        %let keeplist= &keeplist &varlist1;
    %end;
%end;

%put &keeplist;

data newtest;
    set test;
    keep &keeplist;
run;

%mend macrowrapper;

%macrowrapper;

-Mary
----- Original Message -----
From: jlee8071@gmail.com
To: SAS-L@LISTSERV.UGA.EDU
Sent: Monday, September 08, 2008 11:53 PM
Subject: KEEP DROP array variables


Dear SAS users,

I know that one cannot use KEEP or DROP with array variables. But is
there a way to resolve this?

Here is my code. It doesn't work of course.

        do i=1 to 6651;
                if (snps[i] = "DD") then
                        do;
                                keep snps[i];
                        end;
        end;

The original dataset has 6651 variables and  I only want to keep those
variables who has values "DD".

Thank you for the help.
claus