st: filling in existing ids and generating new ids for unique actors

[Erik Aadland <erikaadland@hotmail.com>]

Dear Statalist.
I have an unbalanced panel dataset.
The structure is as follows:
year    actor_id    actor
2000    .           Paul 
2001    .           Paul
2002    .           Paul
2000    .           Sarah
2001    1           Sarah
2002    1           Sarah
2000    .           Simon
2001    2           Simon
2002    2           Simon
I have 2 problems:
1. I want to fill in the missing existing actor_id for those actors that already have an actor_id in some years but not others.
2. I want to generate a new unique actor_id for those actors that have no actor_id in the dataset. This actor_id needs to be different from those already existing for other actors in the dataset.
The variable -actor- lists the unique name for each actor and this unique name could be used as a basis for assigning the actor_id.
Any input on these problems would be greatly appreaciated.
Kind regards,
Erik. 		 	   		  
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