Compute pairwise haversine distances between grid cells

Returns a symmetric \(N \times N\) distance matrix of great-circle distances in kilometres between all pairs of land cells (Eq. 5 of Clavijo Mesa et al., 2026, SF paper).

Usage

hm_distance_matrix(coords)

Arguments

coords

A data.frame with lat and lon columns in decimal degrees. Typically attr(X_land, "coords") from [hm_filter_land_cells()].

Value

A symmetric numeric matrix with diagonal zero.

References

Clavijo Mesa, M.V., Broggi, M., Di Maio, F. & Zio, E. (2026). International Journal of Disaster Risk Reduction, 141, 106172.

See also

[hm_empirical_correlogram()], [hm_filter_land_cells()]

Examples

if (FALSE) { # \dontrun{
X_land <- hm_filter_land_cells(X)
D      <- hm_distance_matrix(attr(X_land, "coords"))
range(D)
} # }