dealing with string variables

[Guest]

Currently I'm working with data sets containg information on bilateral trade for more than 20 countires from 1990 till 2018. I'm interested in values only for Germany. I had the variables named reporter and partner. They have been marked: AUS, CHN, DEU and so on. They were red. I used a code encode reporter, gen(reporternr). After doing so I have variables marked blue. I wanted to keep the observations only for Germany. I typed keep if reporternr==DEU. However, I can see DEU not found. Could anybody help me

[Nick Cox]

reporternr is now numeric, so it is now comparable with a numeric variable or a numeric scalar or a numeric value. But manifestly DEU is not a numeric value yet Stata holds out hope that it is a numeric variable or scalar, but neither is in your dataset; hence the "not found" message.

No, if you want Germany only you can go straight there. say with

keep if reporter == "DEU"  | partner == "DEU"

or more subtly

keep if inlist("DEU", reporter, partner)

and there then seems no point to the encode.