pairdist {spatstat}R Documentation

Pairwise distances

Description

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

Usage

  pairdist(x, y=NULL, method="C")

Arguments

x,y Arguments specifying the x and y coordinates of a set of points. Typically x and y would be numeric vectors of equal length. Alternatively y may be omitted and x may be a point pattern (object of class "ppp") or a list with two components x and y, or a matrix with two columns.
method String specifying which method of calculation to use. Values are "C" and "interpreted".

Details

This function computes the Euclidean distances between all pairs of points, and returns the matrix of distances.

If method = "interpreted" then the distances are computed using interpreted R code only. If method="C" then C code is used. The C code is marginally faster.

Value

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

Author(s)

Pavel Grabarnik pavel.grabar@issp.serpukhov.su and Adrian Baddeley adrian@maths.uwa.edu.au http://www.maths.uwa.edu.au/~adrian/

See Also

nndist, Kest

Examples

   x <- runif(100)
   y <- runif(100)
   d <- pairdist(x, y)
   data(cells)
   d <- pairdist(cells)

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