Create a var with some conditions in a same column

[Guest]

Hi,


I want to create a var with some conditions in a same column. For example,

This is the original data

Id var1

01 c
01 d
02 m
02 f

I want to create a var (var2) =1, if i have "c" and "d" in my Id "01"

Id var1 var2

01 c 1
01 d 1
02 m .
02 f


I hope you can help me
Kind Regards,

S.

[Nick Cox]

clear 
input str2 (Id var1) 
"01" "c"
"01" "d"
"02" "m"
"02" "f"
end 

egen anyc = max(var1 == "c"), by(Id) 
egen anyd = max(var1 == "d"), by(Id) 

gen wanted = anyc & anyd 

list, sepby(Id) 

     +----------------------------------+
     | Id   var1   anyc   anyd   wanted |
     |----------------------------------|
  1. | 01      c      1      1        1 |
  2. | 01      d      1      1        1 |
     |----------------------------------|
  3. | 02      m      0      0        0 |
  4. | 02      f      0      0        0 |
     +----------------------------------+