Accessibility is the ease with which larger cities can be reached from a certain location. This function allows to efficiently calculate accessibility statistics (i.e. travel time to nearby major cities) for polygons. For each polygon, the desired statistic/s (mean, median or sd) is/are returned.
Arguments
- engine
The preferred processing functions from either one of "zonal", "extract" or "exactextract" as character.
- stats
Function to be applied to compute statistics for polygons either single or multiple inputs as character. Supported statistics are: "mean", "median", "sd", "min", "max", "sum" "var".
Value
A function that returns an indicator tibble with city ranges and statisics as variable and corresponding values (in minutes) as value.
Examples
# \dontshow{
mapme.biodiversity:::.copy_resource_dir(file.path(tempdir(), "mapme-data"))
# }
# \dontrun{
library(sf)
library(mapme.biodiversity)
outdir <- file.path(tempdir(), "mapme-data")
dir.create(outdir, showWarnings = FALSE)
mapme_options(
outdir = outdir,
verbose = FALSE
)
aoi <- system.file("extdata", "sierra_de_neiba_478140_2.gpkg",
package = "mapme.biodiversity"
) %>%
read_sf() %>%
get_resources(get_nelson_et_al(ranges = "100k_200k")) %>%
calc_indicators(
calc_traveltime(engine = "extract", stats = c("min", "max"))
) %>%
portfolio_long()
aoi
#> Simple feature collection with 2 features and 8 fields
#> Geometry type: POLYGON
#> Dimension: XY
#> Bounding box: xmin: -71.80933 ymin: 18.57668 xmax: -71.33201 ymax: 18.69931
#> Geodetic CRS: WGS 84
#> # A tibble: 2 × 9
#> WDPAID ISO3 assetid indicator datetime variable unit value
#> <dbl> <chr> <int> <chr> <dttm> <chr> <chr> <dbl>
#> 1 478140 DOM 1 traveltime 2015-01-01 00:00:00 100k_200k_tra… minu… 162
#> 2 478140 DOM 1 traveltime 2015-01-01 00:00:00 100k_200k_tra… minu… 528
#> # ℹ 1 more variable: geom <POLYGON [°]>
# }