st: keep

[Erik Bihagen <erik.bihagen@sofi.su.se>]

Hi Statalisters,

Is there a way to let the keep command do the following?
I want to keep, let's say, three variables v1 v2 v3 before saving data, 
but all these three variables do not exist in all data sets for which I 
want to run the command (I want to do this with a loop using many data 
sets and I use global to define the variables).

I could drop variables instead using "capture drop v4" etc, but that 
would become a very long do file.

Cheers

Erik

--
Erik Bihagen 
Swedish Institute for Social Research 
Stockholm University 
SE-106 91 Stockholm 
Phone: +46 8 16 26 51 
Fax: +46 8 15 46 70


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