https://bbs.pinggu.org/thread-4409959-1-1.html
但是这题我有些问题
新题:
给出Date Amount
01Mar2010 20
02Mar2010 15
03Mar2010 .
04Mar2010 35
05Mar2010 40
Data…..;
Set TOTAL;
Total= Total+ Amount;
Output;
Run;
问最后输出的dataset
A.
Date Amount Total
01Mar2010 20 20
02Mar2010 15 35
03Mar2010 . .
04Mar2010 35 70
05Mar2010 40 110
B.
Date Amount Total
01Mar2010 20 .
02Mar2010 15 .
03Mar2010 . .
04Mar2010 35 .
05Mar2010 40 .
C.
Date Amount Total
01Mar2010 20 20
02Mar2010 15 15
03Mar2010 . .
04Mar2010 35 35
05Mar2010 40 40
D.
Date Amount Total
01Mar2010 20 20
02Mar2010 15 35
03Mar2010 . .
04Mar2010 35 .
05Mar2010 40 .
我想着应该是Total statement中missing value的考点,选的A
我觉得假如total 没有赋值,则选B
retain total = 0; 则选D
对马??