R/custom_utils.R

In crazycapivara/h3forr: An R Interface to H3

#' Get sample [lat, lng] point
#'
#' @export
get_sample_coords <- function() {
  c(37.3615593, -122.0553238)
}

#' Get sample H3 index
#'
#' @export
get_sample_h3_index <- function() {
  get_sample_coords() %>% geo_to_h3()
}

#' Get sample H3 indexes
#'
#' @export
get_sample_h3_indexes <- function() {
  get_sample_h3_index() %>% k_ring()
}

#' Get sample H3 edge index
#'
#' @export
get_sample_h3_edge_index <- function() {
  indexes <- get_sample_h3_indexes()
  get_h3_unidirectional_edge(indexes[1], indexes[2])
}

### TODO: obsolte, remove!
count_h3_obs <- function(h3_index, to_sf = TRUE) {
  freq_tbl <- table(h3_index) %>%
    # as.data.frame(responseName = "count") %>%
    tibble::as_tibble()
  if (!to_sf) return(freq_tbl)

  geo <- h3_to_geo_boundary(freq_tbl$h3_index) %>%
    geo_boundary_to_sf()
  geo$count <- freq_tbl$n
  geo
}

### same as 'tibble::enframe(l, "idx", "h3_index") %>% tidyr::unnest()'
### see below
list_to_df <- function(x, key = "idx", value = "value") {
  result <- lapply(1:length(x), function(i) {
    data.frame(key = i, value = x[[i]])
  })
  df <- do.call(rbind, result)
  names(df) <- c(key, value)
  df
}

h3forr_unnest <- function(x, ...) {
  tibble::enframe(x, ...) %>%
    tidyr::unnest()
}