询问同学后研究出来了
* 使用系统数据库尝试
sysuse auto.dta, clear
*之后初步尝试
xi, prefix(dum_) i.rep78
local varlist="dum_rep78_2 dum_rep78_3 dum_rep78_4 dum_rep78_5 weight"
local new_varlist=""
local i=1
foreach v of local varlist {
qui su `v'
gen `v'_c`i' = `v'-r(mean)
local centred_varname="`v'_c`i'"
local new_varlist="`new_varlist' `centred_varname'"
}
di "`new_varlist'"