n+1

shiyiming

in n+1statement, without remain, the n initial value is 0, 1, or missing? waiting online.Thanks!!!

shiyiming

SAS 9.1的Help Document中SUM Statement有关于这个的解释。
The variable is automatically set to 0 before SAS reads the first observation. The variable's value is retained from one iteration to the next, as if it had appeared in a RETAIN statement.

shiyiming

Thanks! got it.

shiyiming

[code:2uwmbcg5]variable+expression; [/code:2uwmbcg5]

is equivalent to using the SUM function and the RETAIN statement, as shown here:
[code:2uwmbcg5]
retain variable 0;
variable=sum(variable,expression);[/code:2uwmbcg5]