pairdist.psp: Pairwise distances between line segments

Description

Computes the matrix of distances between all pairs of line segments in a line segment pattern.

Usage

## S3 method for class 'psp':
pairdist(X, \dots, method="Fortran")

Arguments

A line segment pattern (object of class "psp").

...

Ignored.

method

String specifying which method of calculation to use. Values are "Fortran" and "interpreted". Usually not specified.

Value

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

Details

This function computes the distance between each pair of line segments in X, and returns the matrix of distances. This is a method for the generic function pairdist for the class "psp".

Distances are calculated using the Hausdorff metric. The Hausdorff distance between two line segments is the maximum distance from any point on one of the segments to the nearest point on the other segment. The argument method is not normally used. It is retained only for checking the validity of the software. If method = "interpreted" then the distances are computed using interpreted R code only. If method="Fortran" (the default) then Fortran code is used. The Fortran code is somewhat faster.

Examples

Run this code

L <- psp(runif(10), runif(10), runif(10), runif(10), owin())
   D <- pairdist(L)

Run the code above in your browser using DataLab

Last chance! 50% off unlimited learning