************************************************
*方法1
clear
input ///
double IID
110101003101
110101007102
end
format IID %20.0f
tostring IID,replace usedisplayformat
gen newvar=substr(IID,-3,3)
list
************************************************
*方法2
clear
input ///
str20 IID
110101003101
110101007102
end
gen newvar=substr(IID,-3,3)
list
************************************************
*************************************************结果
. clear
. input ///
> double IID
IID
1. 110101003101
2. 110101007102
3. end
.
. format IID %20.0f
. tostring IID,replace usedisplayformat
IID was double now str12
.
. gen newvar=substr(IID,-3,3)
. list
+-----------------------+
| IID newvar |
|-----------------------|
1. | 110101003101 101 |
2. | 110101007102 102 |
+-----------------------+
.
.
. clear
. input ///
> str20 IID
IID
1. 110101003101
2. 110101007102
3. end
.
. gen newvar=substr(IID,-3,3)
. list
+-----------------------+
| IID newvar |
|-----------------------|
1. | 110101003101 101 |
2. | 110101007102 102 |
+-----------------------+
.
end of do-file
|