Geographic prefix used for prefix-matching — epid

Returns the leading length characters of the normalised EPID (trimmed, whitespace-collapsed, upper-cased) – the country+province+ district stem used to recover geography from sibling records.

Usage

epid_prefix(epid, length = 11)

Arguments

epid: Character vector of EPID strings.
length: Number of leading characters in the prefix. Default 11.

Value

Character vector of prefixes (NA where the EPID is blank).

Examples

epid_prefix(c("NIE-BOS-XYZ-24-001", NA))
#> [1] "NIE-BOS-XYZ" NA