Creating new var w/ multiple values of another var

[Adam Weber]

Hello, I have two variables, IS and Code. I would like IS to take on different values depending on what Code is. For example, I would like IS to equal 10401 if Code = 10085, 10087, 10090, 10091, 10095, or 60031. I would like IS to equal 10402 if Code = 10094, 10164, 60027, 60029, 60032, 60033 or 60034.

In this way I am trying to map about 900 Code values to about 100 IS values. Is there a relatively quick way I can do this using loops and groups instead of doing replace IS over and over again? I am very new to Stata and do not have much experience.

[Marcos Almeida]

Welcome to the Stata Forum / Statalist,

I fail to envisage a place for a loop here.

If I understood right, it seems you need to use - replace if -, for you have specific values to replace.

[Adam Weber]

Thank you for responding.

Yes I am using -replace if- a lot (see below). I am just wondering if there is an easier way.

gen IS = 10401 if Code==10085
replace IS = 10401 if Code==10087
replace IS = 10401 if Code==10090
replace IS = 10401 if Code==10091
replace IS = 10401 if Code==10095
replace IS = 10401 if Code==60031

replace IS = 10402 if Code==10094
replace IS = 10402 if Code==10164
replace IS = 10402 if Code==60027
replace IS = 10402 if Code==60029
replace IS = 10402 if Code==60032
replace IS = 10402 if Code==60033
replace IS = 10402 if Code==60034
replace IS = 10402 if Code==60035
replace IS = 10402 if Code==60100

replace IS = 10801 if Code==10134
replace IS = 10801 if Code==10136
replace IS = 10801 if Code==10143
replace IS = 10801 if Code==60072
replace IS = 10801 if Code==60104
replace IS = 10801 if Code==60209

replace IS = 10802 if Code==10059
replace IS = 10802 if Code==10132
replace IS = 10802 if Code==10138
replace IS = 10802 if Code==10148
replace IS = 10802 if Code==60063
replace IS = 10802 if Code==60064
replace IS = 10802 if Code==60073
replace IS = 10802 if Code==86258

[William Lisowski]

The merge command may be the best way of attacking this problem. Here's an example based on your data.

// invent up example data
clear
input float Code IS
10085 10401 
10087 10401 
10090 10401 
10091 10401 
10095 10401 
60031 10401 
10094 10402 
10164 10402 
60027 10402 
60029 10402 
60032 10402 
60033 10402 
60034 10402 
60035 10402 
60100 10402 
end
tempfile IS
save `IS'

clear
input float(id Code)
101 10085
102 10087
103 10090
104 10091
105 10094
106 10095
107 10090
108 60027
109 60029
110 60031
111 60032
112 60035
113 60100
114 66666
end
tempfile master
save `master'

// demonstrate technique
use `master', clear
merge m:1 Code using `IS'

list, clean

drop if _merge==2
drop _merge
sort id

list, clean

. // demonstrate technique
. use `master', clear

. merge m:1 Code using `IS'

    Result                           # of obs.
    -----------------------------------------
    not matched                             4
        from master                         1  (_merge==1)
        from using                          3  (_merge==2)

    matched                                13  (_merge==3)
    -----------------------------------------

. 
. list, clean

        id    Code      IS            _merge  
  1.   101   10085   10401       matched (3)  
  2.   102   10087   10401       matched (3)  
  3.   103   10090   10401       matched (3)  
  4.   107   10090   10401       matched (3)  
  5.   104   10091   10401       matched (3)  
  6.   105   10094   10402       matched (3)  
  7.   106   10095   10401       matched (3)  
  8.   108   60027   10402       matched (3)  
  9.   109   60029   10402       matched (3)  
 10.   110   60031   10401       matched (3)  
 11.   111   60032   10402       matched (3)  
 12.   112   60035   10402       matched (3)  
 13.   113   60100   10402       matched (3)  
 14.   114   66666       .   master only (1)  
 15.     .   10164   10402    using only (2)  
 16.     .   60033   10402    using only (2)  
 17.     .   60034   10402    using only (2)  

. 
. drop if _merge==2
(3 observations deleted)

. drop _merge

. sort id

. 
. list, clean

        id    Code      IS  
  1.   101   10085   10401  
  2.   102   10087   10401  
  3.   103   10090   10401  
  4.   104   10091   10401  
  5.   105   10094   10402  
  6.   106   10095   10401  
  7.   107   10090   10401  
  8.   108   60027   10402  
  9.   109   60029   10402  
 10.   110   60031   10401  
 11.   111   60032   10402  
 12.   112   60035   10402  
 13.   113   60100   10402  
 14.   114   66666       .