面板数据赋值求助

* Example generated by -dataex-. To install: ssc install dataex
clear
input float(policy_year number)
201611  1
201612  2
201701  3
201701  4
201701  5
201701  6
201702  7
201702  8
201703  9
201703 10
201703 11
201703 12
201703 13
201704 14
201704 15
201704 16
201705 17
201706 18
201707 19
201708 20
201708 21
201708 22
201711 23
201806 24
201812 25
201901 26
201912 27
end
[/CODE]
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Listed 27 out of 27 observations




数据有很多条，想实现对201701的number赋值为3，201702的number赋值为4,201703的number赋值为5。。。。。

首先需要提取出policy_year的前六位数字
tostring policy_year , g(policy_year_6) format(%04.0f)
replace policy_year_6 = substr(policy_year_6,1,6)
destring policy_year_6, replace
然后进行赋值
replace number = 3 if policy_year_6 == 201701
......

先提取变量的前六位数字
tostring policy_year, g(id) format(%04.0f)
replace id = substr(id, 1,2)
destring id, replace
然后再分别对其赋值
replace number = 3 if id == 201701