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Compute distances between two sf objects in km

Source: R/measurement.R
pk_distance.Rd

Reprojects internally to UTM Zone 42N for accurate metric distances.

Usage

pk_distance(x, y, by = c("centroid", "edge"))

Arguments

x

An sf object.

y

An sf object.

by

Character. "centroid" (default) for centroid-to-centroid distances. "edge" for nearest-point-on-boundary distances.

Value

Returns a numeric matrix (class "matrix") of distances in kilometres, with dimensions nrow(x) by nrow(y).

When by = "centroid", distances are measured between polygon centroids. When by = "edge", distances are measured between the closest points on polygon boundaries. The output represents the shortest straight-line distance between features.

Examples

provinces <- get_provinces()
d <- pk_distance(provinces, provinces)
#> Warning: st_centroid assumes attributes are constant over geometries
#> Warning: st_centroid assumes attributes are constant over geometries
print(d)
#>  [1]    0.00000  996.67608  220.58232   85.14532  214.47991  395.26898
#>  [7] 1017.39047  996.67608    0.00000 1196.76855  913.32286  847.16126
#> [13]  667.66333  387.44971  220.58232 1196.76855    0.00000  291.92462
#> [19]  359.33835  615.83990 1237.20137   85.14532  913.32286  291.92462
#> [25]    0.00000  146.96871  332.30893  947.48230  214.47991  847.16126
#> [31]  359.33835  146.96871    0.00000  372.12890  940.92748  395.26898
#> [37]  667.66333  615.83990  332.30893  372.12890    0.00000  624.16408
#> [43] 1017.39047  387.44971 1237.20137  947.48230  940.92748  624.16408
#> [49]    0.00000

# Edge-to-edge distances
d_edge <- pk_distance(provinces, provinces, by = "edge")