緯度経度から住所を求める関数

latlong2city.R

# 住所(市)判定
#' @param sp_polygon object of class sf, sfc or sfg
#' @param lon longitude
#' @param lat latitude
find_city <- function(sp_polygon = df, lon = lon, lat = lat) {

  which.row <- sf::st_contains(sp_polygon, sf::st_point(c(lon, lat)), sparse = FALSE) %>%
    grep(TRUE, .)

  if (identical(which.row, integer(0)) == TRUE) {
    message("指定した座標がポリゴンに含まれません")
  } else {
    geos <- sp_polygon[which.row, ] %>%
      dplyr::mutate_if(is.factor, as.character) #%>%
      #dplyr::mutate_at(dplyr::vars(N03_001:N03_004), dplyr::funs(dplyr::if_else(condition = is.na(.), true = "", false = .)))

    #res <- tibble::data_frame(
    #  #city_code = geos$N03_007,
    #  city_name = paste0(geos$N03_001, geos$N03_002, geos$N03_003, geos$N03_004) %>%
    #    stringr::str_replace_all("NA", "")
    #)
      city_name = paste0(geos$N03_001, geos$N03_002, geos$N03_003, geos$N03_004) %>%
        stringr::str_replace_all("NA", "")

    return(city_name)
  }
}

# 住所(街レベル)判定
#' @param sp_polygon object of class sf, sfc or sfg
#' @param lon longitude
#' @param lat latitude
find_place <- function(sp_polygon = df, lon = lon, lat = lat) {
  
  which.row <- sf::st_contains(sp_polygon, sf::st_point(c(lon, lat)), sparse = FALSE) %>%
    grep(TRUE, .)
  
  if (identical(which.row, integer(0)) == TRUE) {
    message("指定した座標がポリゴンに含まれません")
  } else {
    geos <- sp_polygon[which.row, ] %>%
      dplyr::mutate_if(is.factor, as.character) #%>%
    #dplyr::mutate_at(dplyr::vars(N03_001:N03_004), dplyr::funs(dplyr::if_else(condition = is.na(.), true = "", false = .)))
    
    place_name = paste0(geos$KEN_NAME, geos$GST_NAME, geos$MOJI) %>%
      stringr::str_replace_all("NA", "")
    
    return(place_name)
  }
}