osbng (version 0.2.0)

bng_distance: Distance calculations

Description

Compute Euclidean distances between BNG references and distance-based neighbours lists.

Usage

bng_dwithin(bng_ref, d, ...)
bng_distance(bng_ref1, bng_ref2, by_element = FALSE, edge_to_edge = FALSE)

Value

list containing an unordered vector of BNGReference objects around a given grid square within an absolute distance d.

If by_element is FALSE

bng_distance returns a dense numeric matrix of dimension length(x) by length(y); otherwise it returns a numeric vector the same length as x and y with an error raised if the lengths of x and y are unequal. Distances involving invalid references are NA.

Arguments

bng_ref

object of class BNGReference.

d

numeric. Distance expressed in metres.

...

additional parameters. Not currently used.

bng_ref1, bng_ref2

object of BNGReference

by_element

logical. If TRUE, return a vector with distance between each pair of BNG references. An error is raised if the BNGReference objects are not the same length. Default is FALSE, to return a dense matrix with all pairwise distances.

edge_to_edge

Logical. Should the distances be measured between the edges of the grid references? Default is FALSE to use the centroid.

Details

bng_dwithin returns all grids squares for which any part of the boundary is within the distance d of any part of bng_ref's boundary.

Examples

bng_dwithin(as_bng_reference("SU1234"), 1000)

bng_dwithin(as_bng_reference("SU1234"), 1001)


ref1 <- as_bng_reference("SE1433")

bng_distance(ref1, as_bng_reference("SE1631"))

bng_distance(ref1, as_bng_reference("SENW"))

ref2 <- as_bng_reference(c("SE1533", "SE1631", "SE"))

bng_distance(ref1, ref2)

bng_distance(ref2)

ref3 <- as_bng_reference(c("SE1433", "SE1244"))

bng_distance(ref3, ref2)

bng_distance(ref3, ref2[1:2], by_element = TRUE)

bng_distance(ref1, ref2, edge_to_edge = TRUE)