sas数据集转换（举例如下，实际数据集行数很多）

id	x
1	a1
2
3
4	b2
5
6
7	b2
8
9	yyy7
10
11
12
13	ii100
14
15

变换成如下格式

id	a1	b2	yyy7	ii100
1	1	0	0	0
2	0	0	0	0
3	0	0	0	0
4	0	1	0	0
5	0	0	0	0
6	0	0	0	0
7	0	1	0	0
8	0	0	0	0
9	0	0	1	0
10	0	0	0	0
11	0	0	0	0
12	0	0	0	0
13	0	0	0	1
14	0	0	0	0
15	0	0	0	0

data test;
infile cards missover;
input id x$;
cards;
1 a1
2  
3  
4 b2
5  
6  
7 b2
8  
9 yyy7
10  
11  
12  
13 ii100
14  
15  
;
run;

data test1;
set test ;
if x ne '' then aval=1;
run;

proc transpose data=test1 out=test2(drop=_name_);
by id;
id x;
var aval;
run;

data test3;
set test2;
array a(*) _numeric_;
do i=1 to dim(a);
if a(i)=. then a(i)=0;
end;
drop  i;
run;

data a;
infile cards missover;
input id x$;
if x="a1" then a1=1;else a1=0;
if x="b2" then b2=1;else b2=0;
if x="yyy7" then yyy7=1;else yyy7=0;
if x="ii100" then ii100=1;else ii100=0;
drop x;
cards;
1 a1
2  
3  
4 b2
5  
6  
7 b2
8  
9 yyy7
10  
11  
12  
13 ii100
14  
15  
;
run;
proc print data=a;
run;

结果：
--------------------------------------------------------------------------------
The SAS System


Obs id a1 b2 yyy7 ii100
1 1 1 0 0 0
2 2 0 0 0 0
3 3 0 0 0 0
4 4 0 1 0 0
5 5 0 0 0 0
6 6 0 0 0 0
7 7 0 1 0 0
8 8 0 0 0 0
9 9 0 0 1 0
10 10 0 0 0 0
11 11 0 0 0 0
12 12 0 0 0 0
13 13 0 0 0 1
14 14 0 0 0 0
15 15 0 0 0 0

谢谢各位的帮助!