咳咳唐 发表于 2020-2-17 17:43 
gen a =1
egen suma = sum(a), by(code)
drop if suma <= 2
不知道是我哪里输错了命令,还请大神指导下
输完显示:
. gen a =1<br>
invalid syntax
r(198);
.
. egen suma = sum(a), by(code)<br>
unknown egen function sum()
r(133);
.
. drop if suma <= 2
suma not found
r(111);