Computes the Euclidean distance between two nodes using the function
sf::st_distance(). If the CRS is not a Cartesian system, the Great Circle
distance will be used instead.
distance_euclidean(sites, ...)an sf object of type POINT. A spatial object
containing coordinates of sites. Note that the first column must be the
node label created by the function create_node_labels().
other argument to pass to sf::st_distance().
A three-column data.frame with:
from, the first node
to, the second node
weight, the Euclidean distance between the two nodes
# Import Adour sites ----
path_to_file <- system.file("extdata", "adour_survey_sampling.csv",
package = "chessboard")
adour_sites <- read.csv(path_to_file)
# Select the 15 first sites ----
adour_sites <- adour_sites[1:15, ]
# Create node labels ----
adour_sites <- create_node_labels(adour_sites,
location = "location",
transect = "transect",
quadrat = "quadrat")
# Convert sites to sf object (POINTS) ----
adour_sites <- sf::st_as_sf(adour_sites, coords = c("longitude", "latitude"),
crs = "epsg:2154")
# Compute distances between pairs of sites ----
weights <- distance_euclidean(adour_sites)
head(weights)
#> from to weight
#> 1 1-1 1-1 0.000
#> 2 1-1 1-2 2500.469
#> 3 1-1 1-3 5000.938
#> 4 1-1 1-4 7501.407
#> 5 1-1 1-5 10001.876
#> 6 1-1 2-1 2500.469