以上代码中,运行以后RC值为什么是low而不是high,我在sas里面跑出来的结果依然是low,不知道原因,求教
原题目是:
The data set SASHELP.PRDSALE has 50 observations. What is the value of the variable RC when the macro finishes execution?
A.low
B.high
C.Begin
D.Before Execution
Because the %LET statements are always processed by the macro processor before the DATA step is executed, the value is always whatever the last %LET statement assigns.中文意思是%LET statements给宏赋值,因为 宏赋值总是比DATA步优先, 所以DATA步里的if then 对%LET statements 赋值没有处理能力, 得到的 宏值 总是最后%LET statement的赋值。这里最后的%LET statements是%let rc = low;所以得到的结果就是low。