spatstat (version 1.48-0)

Extract.linnet: Extract Subset of Linear Network

Description

Extract a subset of a linear network.

Usage

"["(x, i, ..., snip=TRUE)

Arguments

x

A linear network (object of class "linnet").

i

Spatial window defining the subregion. An object of class "owin".

snip

Logical. If TRUE (the default), segments of x which cross the boundary of i will be cut by the boundary. If FALSE, these segments will be deleted.

...

Ignored.

Value

Another linear network (object of class "linnet").

Details

This function computes the intersection between the linear network x and the domain specified by i. This function is a method for the subset operator "[" for linear networks (objects of class "linnet"). It is provided mainly for completeness.

The index i should be a window.

The argument snip specifies what to do with segments of x which cross the boundary of i. If snip=FALSE, such segments are simply deleted. If snip=TRUE (the default), such segments are cut into pieces by the boundary of i, and those pieces which lie inside the window i are included in the resulting network.

Examples

  p <- par(mfrow=c(1,2), mar=0.2+c(0,0,1,0))
  B <- owin(c(0.1,0.7),c(0.19,0.6))

  plot(simplenet, main="x[w, snip=TRUE]")
  plot(simplenet[B], add=TRUE, col="green", lwd=3)
  plot(B, add=TRUE, border="red", lty=3)

  plot(simplenet, main="x[w, snip=FALSE]")
  plot(simplenet[B, snip=FALSE], add=TRUE, col="green", lwd=3)
  plot(B, add=TRUE, border="red", lty=3)

  par(p)