This function allows to efficiently calculate elevation statistics for polygons. For each polygon, the desired statistic/s (mean, median or sd) is/are returned. The required resources for this indicator are:
Details
The following arguments can be set:
- stats_elevation
Function to be applied to compute statistics for polygons either one or multiple inputs as character. Supported statistics are: "mean", "median", "sd", "min", "max", "sum" "var".
- engine
The preferred processing functions from either one of "zonal", "extract" or "exactextract" as character.
Examples
if (Sys.getenv("NOT_CRAN") == "true") {
library(sf)
library(mapme.biodiversity)
temp_loc <- file.path(tempdir(), "mapme.biodiversity")
if (!file.exists(temp_loc)) {
dir.create(temp_loc)
resource_dir <- system.file("res", package = "mapme.biodiversity")
file.copy(resource_dir, temp_loc, recursive = TRUE)
}
(try(aoi <- system.file("extdata", "sierra_de_neiba_478140_2.gpkg",
package = "mapme.biodiversity"
) %>%
read_sf() %>%
init_portfolio(
years = 2000:2020,
outdir = file.path(temp_loc, "res"),
tmpdir = tempdir(),
add_resources = FALSE,
verbose = FALSE
) %>%
get_resources("nasa_srtm") %>%
calc_indicators("elevation",
stats_elevation = c("mean", "median", "sd", "var"), engine = "extract"
) %>%
tidyr::unnest(elevation)))
}
#> Error in map(.x, .f, ...) : ℹ In index: 4.
#> Caused by error:
#> ! [extract] not a valid function
#> Warning: Error occured at polygon 1 with the following error message: Error in map(.x, .f, ...) : ℹ In index: 4.
#> Caused by error:
#> ! [extract] not a valid function
#> .
#> Returning NAs.
#> Simple feature collection with 1 feature and 6 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: 1 × 7
#> WDPAID NAME DESIG_ENG ISO3 assetid value geom
#> <dbl> <chr> <chr> <chr> <int> <lgl> <POLYGON [°]>
#> 1 478140 Sierra de Neiba National… DOM 1 NA ((-71.76134 18.66333, -7…