一列数据我需要求第i到i+30数据的方差,SAS中怎么实现

Question

一列数据我需要求第i到i+30数据的方差,SAS中怎么实现

Answer 1

data tmp;
input a @@;
datalines;
1 2 3 4 5 6 7 8 9 10
;
run;
%macro a;
data get;
%let i=5; /*i的初始值你肯定有的*/
set tmp (firstobs=&i obs=%eval(&i+30));
run;
%mend a;
%a;
proc means data=get;
var a;
output out=result n=totalnumber var=variance;
run;
proc print data=result(keep=totalnumber variance); run;