请问数据集的转换问题

shiyiming

xic，我把你的程序稍微改动了一下，但是我不太明白为什么不能达到预期效果，请指教
data a;
input a b c r;
datalines;
1 5 4 22
1 5 4 4
1 5 4 9
1 5 4 22
1 5 4 4
1 5 4 9
2 7 3 11
2 7 3 5
2 7 3 7
2 7 3 11
;

proc sql;
create table a as
select *, count(*) as cnt
from a
group by a, b, c;
quit;

%macro expand;
%global count;

proc sql noprint;
select max(cnt) into :maxcnt
from a;
quit;

data b(drop=r);
retain
%do i=1 %to &maxcnt;
r&i
%end;;
set a;
by a b c;
if first.c then do;
%do i=1 %to &maxcnt;
r&i=.;
%end;
%let count=1;
r&count=r;
end;
else do;
%let count=count+1;
r&count=r;
end;
if last.c then output;
run;

%mend;

%expand;

shiyiming

I think you have mixed up the macro variable with a SAS variable in data step.  Is COUNT a macro variable or variable in data step, in either way, the line %let count=count+1 will not work.

shiyiming

[quote="willon":5bc30]proc transpose data=tem out=tem1(drop=_name_) prefix=r;
by a b c;
run;[/quote:5bc30]

I think Willon's solution is one of the best (simple and common), providing the data set is sorted by a b c, and the the number of r(r1,r2,...,rn) is smaller than 32764 (SAS on windows platform).