行列转换简单示例Before转换

Obs	TRTN	AGEGR1N	AVAL
1	1	1	11
2	1	2	12
3	1	3	13
4	2	1	21
5	2	2	22
6	2	3	23

After转换

Obs	TRTN	AGEGR_1	AGEGR_2	AGEGR_3
1	1	11	12	13
2	2	21	22	23

>首选方案proc transpose一发入魂？\
code示例如下
data test;
TRTN=1; AGEGR1N=1; AVAL=11; output;
TRTN=1; AGEGR1N=2; AVAL=12; output;
TRTN=1; AGEGR1N=3; AVAL=13; output;
TRTN=2; AGEGR1N=1; AVAL=21; output;
TRTN=2; AGEGR1N=2; AVAL=22; output;
TRTN=2; AGEGR1N=3; AVAL=23; output;
run;
proc transpose data=test out=test_tran0 prefix=AGEGR_;
by TRTN;
  id AGEGR1N;
  var AVAL;
run;
>替代方案1利用data过程步的retain+if first／if last组合
data test_tran1;
  set test;
  by TRTN AGEGR1N;
  retain AGEGR_1 AGEGR_2 AGEGR_3;
  if first.TRTN then call missing(AGEGR_1,AGEGR_2,AGEGR_3);
  if AGEGR1N=1 then AGEGR_1=AVAL;
  if AGEGR1N=2 then AGEGR_2=AVAL;
  if AGEGR1N=3 then AGEGR_3=AVAL;
  if last.TRTN then output;
  keep TRTN AGEGR_1 AGEGR_2 AGEGR_3;
run;
>替代方案2讨厌data过程步，特别偏爱sql的小伙伴们可以看看下面示例code，估计很少有人用，我反正是没见过其他sp这个写过，嘿嘿
proc sql noprint;
  create table test_tran2 as
  select distinct TRTN
            , max(case when AGEGR1N=1 then AVAL else . end) as AGEGR_1
            , max(case when AGEGR1N=2 then AVAL else . end) as AGEGR_2
            , max(case when AGEGR1N=3 then AVAL else . end) as AGEGR_3
  from test
  group by TRTN;
quit;
>两种方案的执行结果


结论

码code是个辛苦的体力活，偶尔换个解法，换个思维，枯燥也许会变的有趣，工作也许更有动力。
以上介绍仅供参考，具体问题具体对待，如果有更有趣的解法欢迎留言探讨，共同进步。