st: Data management

[Jeetendra Aryal <jeetendra.aryal@umb.no>]

Dear Statalists
I have a big data set which is as follows:
HHN   PN    Rental type
1          1        1
1          2        0
1          3        0
2          1        1
2          2        1
3          1        1
3          2        0
3          3        1
4          1        1
4          2        1
4          3        1
5          1        0
5          2        1
5          3        1
 
Now the question is: Each household has more than one plot of land. The household can use it or rent it out or both. I want to keep only those households which have both rental types. For example, in the above dataset I want to keep only household number 1, 3 and 5. Is there any way that I can do it easily, rather than doing manually?
Best regards,
Jeetendra Aryal
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