spatstat.geom (version 3.3-5)

pairdist.ppx: Pairwise Distances in Any Dimensions

Description

Computes the matrix of distances between all pairs of points in a multi-dimensional point pattern.

Usage

# S3 method for ppx
pairdist(X, ...)

Value

A square matrix whose [i,j] entry is the distance between the points numbered i and j.

Arguments

X

A point pattern (object of class "ppx").

...

Arguments passed to coords.ppx to determine which coordinates should be used.

Distance values

The values returned by pairdist(X, temporal=FALSE) are distances, expressed as multiples of the unit of length of the spatial coordinates in X. The unit of length is given by unitname(X).

Note that, if the unit of length in X is a composite expression such as ‘2 microns’, then the values of pairdist(X, temporal=FALSE) are expressed as multiples of 2 microns, rather than being expressed in microns.

Author

Adrian Baddeley

Details

This is a method for the generic function pairdist.

Given a multi-dimensional point pattern X (an object of class "ppx"), this function computes the Euclidean distances between all pairs of points in X, and returns the matrix of distances.

By default, both spatial and temporal coordinates are extracted. To obtain the spatial distance between points in a space-time point pattern, set temporal=FALSE.

See Also

pairdist, crossdist, nndist

Examples

   df <- data.frame(x=runif(4),y=runif(4),z=runif(4),w=runif(4))
   X <- ppx(data=df)
   pairdist(X)