Official county codes for county names written any way

Turns county names — or county numbers — as they appear in anyone's data into the official two-digit codes of the 2019 census frame, the codes knbs_geographies() and the census tables use. Built for mutate():

my_data |> mutate(geo_code = knbs_county_code(county))

KNBS's own sources disagree on names: the census writes "Murang'a", "Tharaka-Nithi" and "Nairobi City", the Data Portal "MURANGA", "THARAKA NITHI" and "NAIROBI". Both, and the usual variants elsewhere, resolve to the same codes.

Usage

knbs_county_code(
  x,
  vintage = 2019L,
  cache = knbs_option("cache"),
  refresh = FALSE
)

Arguments

x: County names or numbers: a character, numeric or factor vector.
vintage: The census frame to match against. Only 2019 is available.
cache: Whether to use the local cache for the reference names.
refresh: Whether to re-read the reference names.

Value

A character vector the length of x, holding two-digit codes, and NA where a value did not match.

Details

A name matches when it is the official name once case, punctuation, spacing and apostrophes are set aside and the words "County", "City", "Government", "of" and "the" are dropped: "Taita Taveta", "TAITA/TAVETA" and "Taita-Taveta County" are all "06", "Nairobi" and "Nairobi City County" both "47". A number from 1 to 47, written 1, "1" or "01", is taken as the county number. "Kenya" and "National" give the census code for the whole country, "00".

Nothing else is matched. There is no list of alternative names, so a misspelling stays unmatched rather than being guessed at; the warning names each unmatched value and, where one official name is close, says which. knbs_match_counties() shows how every value was matched.

The official names are read from the census frame through knbs_geographies(), once, and cached. If the census service cannot be reached, the 47 counties' statutory names and numbers built into the package are used instead; they are the census frame's own, and the package's tests hold them identical.

Examples

if (FALSE) { # interactive()
knbs_county_code(c("Murang'a", "MURANGA", "Nairobi", "taita/taveta", "47"))
#> [1] "21" "21" "47" "06" "47"
}