st: changing values of a string variable

[tashi lama <ltashi32@hotmail.com>]

Hello All,

 I found matters similar to what I am going to post have been been discussed in the past but I am not sure if I understood. Here is my dataset 
 

hits firms
3     id_6429
10    id_131
8     id_2837

12    id_90

 

The problem is to have sth like this  

 

hits    firms

3     .

10    id_131
8     .

12    .


so I said    1.  encode firm, gen(firm1)

                 replace firm1=. if firm1!=id_131

                 drop firms

 

 

 

 I also tried   2.   replace firms="" if firms!="id_131"         

 

 

 

It didn't give me the expected output although I feel like my codes are correct at least in principle. Any idea?

 

Thanking, 

Tashi 

    

  		 	   		  
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