SAS初学,看到别人一下程序:
不理解其中if 和%if有什么区别,希望高手解答,在我看来好像没有区别啊
%macro gain_data;
data all_dev;
set dev.&dev_master.;
if &y. in (0,1);
intercept=1;
n=1;
%if %symexist(sam_num) = 1 %then %do;
%include "&sam_num.";
%include "&samchar.";
%include "&samscr.";
rebin_score= int(scor_rebin*10000)/10000;
%end;
........