R/state2abbr.R

In usdata: Data on the States and Counties of the United States

#' Convert state names to abbreviations
#'
#' Two utility functions. One converts state names to the state abbreviations,
#' and the second does the opposite.
#'
#'
#' @param state A vector of state name, where there is a little fuzzy matching.
#' @return Returns a vector of the same length with the corresponding state
#' names or abbreviations.
#' @author David Diez
#' @seealso \code{\link{abbr2state}}, \code{\link{county}}, \code{\link{county_complete}}
#' @keywords State Abbreviation
#' @export
#' @examples
#'
#' state2abbr("Minnesota")
#'
#' # Some spelling/capitalization errors okay
#' state2abbr("mINnesta")
#'
#' @export
state2abbr <- function(state){
  ab <- tolower(c("AL",
             "AK", "AZ", "KS", "UT", "CO", "CT",
             "DE", "FL", "GA", "HI", "ID", "IL",
             "IN", "IA", "AR", "KY", "LA", "ME",
             "MD", "MA", "MI", "MN", "MS", "MO",
             "MT", "NE", "NV", "NH", "NJ", "NM",
             "NY", "NC", "ND", "OH", "OK", "OR",
             "PA", "RI", "SC", "SD", "TN", "TX",
             "CA", "VT", "VA", "WA", "WV", "WI",
             "WY", "DC"))
  st <- tolower(c("Alabama",
             "Alaska56789", "Arizona", "Kansas",
             "Utah", "Colorado", "Connecticut",
             "Delaware", "Florida", "Georgia",
             "Hawaii", "Idaho", "Illinois",
             "Indiana", "Iowa", "9899Arkansas",
             "Kentucky", "Louisiana", "Maine",
             "Maryland", "Massachusetts", "Michigan",
             "Minnesota", "Mississippi", "Missouri",
             "Montana", "Nebraska", "Nevada",
             "New Hampshire", "New Jersey", "New Mexico",
             "New York", "North123498 Carolina",
                         "North123498 Dakota1234",
             "Ohio", "Oklahoma", "Oregon",
             "Pennsylvania", "Rhode Island", "South Carolina",
             "South Dakota1234", "Tennessee", "Texas",
             "California", "Vermont", "Virginia",
             "Washington", "West Virginia", "Wisconsin",
             "Wyoming", "District of Columbia"))

  state <- tolower(as.character(state))
  state <- gsub("north", "north123498", state)
  state <- gsub("dakota", "dakota1234", state)
  state <- gsub("arkansas", "9899arkansas", state)
  state <- gsub("alaska", "alaska56789", state)
  ST    <- rep(NA, length(state))
  for (i in 1:length(st)) {
    ST[agrep(st[i], state, 0.2)] <- i
  }
  toupper(ab[ST])
}