Calculate occurrence count, centroid coordinates, latitudinal range (degrees), great circle distance (km), mean pairwise distance (km), and summed minimum spanning tree length (km) for spatial point coordinates.
Arguments
- coords
2-column
data.frame
ormatrix
containing x- and y-coordinates, respectively (e.g. longitude and latitude).- crs
Coordinate reference system as a GDAL text string, EPSG code, or object of class
crs
. Default is latitude-longitude (EPSG:4326
).
Details
Coordinates and their distances are computed with respect to the original
coordinate reference system if supplied, except in calculation of latitudinal
range, for which projected coordinates are transformed to geodetic ones.
If crs
is unspecified, by default points are assumed to be given in
latitude-longitude and distances are calculated with spherical geometry.
Duplicate coordinates will be removed. If a single unique point is supplied,
all distance measures returned will be NA
.
Examples
# generate 20 occurrences for a pseudo-species
# centred on Yellowstone National Park (latitude-longitude)
# normally distributed with a standard deviation ~110 km
set.seed(2)
x <- rnorm(20, 110.5885, 2)
y <- rnorm(20, 44.4280, 1)
pts <- cbind(x,y)
rangeSize(pts)
#> nLoc centroidX centroidY latRange greatCircDist meanPairDist minSpanTree
#> [1,] 20 110.9828 44.44622 4.542526 697.9476 269.6437 1855.473