st: Atribute variable value to String

[Lucas Ferreira Mation <lucasmation@gmail.com>]

I have a dataset with the variables: sector_code sector_name year Y
I want to create the graph line  Y year   for each sector. As there
are too many sectors (500) , i want to make a loop like:
global sector_list 01112 01120 // the actual list is much longer
foreach s in $sector_list {
preserve
      keep if clas_cnae=="`s'"
      twoway (line Y ano) , title ( /* SOMEHOW THE VALUE IN VARIABLE
sector_name*/)
restore
}
How can I do that? I guess my question is equivlent to: how to
atribute the content of a string variable to a scalar (which I could
later use in the loop)? That would be the easyest way if I knew how.
Another solution would be to create a sector_code sector_name matrix
in mata (because they are string variables, so a Stata matrix won´t
accept) and loop over the lines of that matrix. Again, the sector list
is too big sector for manual entry. So I need a way to import string
variables from the Stata dataset to the mata matrix. How do I do that?
The mata command st_data does that but does not work for string
varibles (it imports them as missing)
thank you
Lucas Mation
Ipea-Instituto de Pesquisa Econômica Aplicada (Brasil)

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