有lag function，那有lead function不？

bobguy 发表于 2010-9-29 09:18

一眼瞬间 发表于 2010-9-28 12:35
想算未来两期和这期数据之差，

不知道用什么function呢？

或者能用其他什么办法解决不？

谢谢了~

There is no lead function in SAS.

But you can do it with in many ways.
here is a couple of ideas you can try.
1) point access option in data step.
2) merge the data set itself without a by statement

yes, yes. That is how I sloved it.

楼上的，怎么解决啊，没看懂，用汉语说不很好吗