DATA A; INPUT HR SBP DBP;
DATALINES;
80 160 100
70 150 90
60 140 80
;
PROC MEANS DATA=A NOPRINT;
VAR HR SBP DBP;
OUTPUT OUT=B
MEAN=M_HR M_SBP M_DBP;
RUN;
DATA C11;
SET A;
IF _N_=1 THEN SET B;
HRPRE=HR/M_HR*100;
SBPPRE=SBP/M_SBP*100;
DBPPRE=DBP/M_DBP*100;
DROP M_HR M_SBP M_DBP _TYPE_ _FREQ_;
DATALINES;
RUN;
请问这个程序中的if 语句是循环么?结果应该是怎么样的啊?